These are all features of the moon, the Earth's natural satellite?
|
|
More plans are also underway for future visits to Earth's natural satellite.
|
|
A lingering lunar mystery is whether our natural satellite contains any frozen water.
|
|
If successful, the mission could answer fundamental questions about Earth's only natural satellite.
|
|
Earth's natural satellite is at full phase and at its closest point in orbit.
|
|
Our natural satellite contains many precious materials, such as water, iron ore, and helium-3.
|
|
For all of humankind's accomplishments, a trip beyond the moon — Earth's own natural satellite — remains elusive.
|
|
Thursday's landing is the first time humanity has landed anything on Earth's natural satellite since 22016.
|
|
Then, we're taking you to the moon for a more detailed look at our natural satellite.
|
|
Its legacy as first artificial satellite of Earth's natural satellite, however, remains intact 50 years on.
|
|
Still, the moon, our closest natural satellite, seems to hold a pull for scientists that's more than gravitational.
|
|
Our natural satellite is tidally locked to Earth, forcing us to gaze perpetually upon one of its two hemispheres.
|
|
Meanwhile, as the moon tugs on Earth, our natural satellite distances itself about 1.5 inches per year from Earth.
|
|
In this case, they found a natural satellite that was pulled into Earth's orbit, likely two or three years ago.
|
|
Rather than appearing as a black spot in the heavens, however, our sole natural satellite will exude a blood-red hue.
|
|
Measuring nearly 3,200 miles (5,100 km) in diameter, Titan is the Solar System's second largest moon and Saturn's largest natural satellite.
|
|
It's an astonishing piece of art, and it's probably the best look that I'll ever get of our closest natural satellite.
|
|
Twelve years ago, astronomers with the Catalina Sky Survey detected our planet's first and only known natural satellite other than the Moon.
|
|
Bridenstine said shifting political priorities were the key reason NASA had not returned to the surface of Earth's natural satellite since then.
|
|
This half-lit view of Enceladus bears a passing resemblance to similar views of Earth's own natural satellite, but the similarities end there.
|
|
He figured that Pluto either had a natural satellite or boasted an enormous mountain that towered thousands of miles above the planet&aposs surface.
|
|
Millions of people gazed into the night sky or onto video feeds to see a stunning coppery-red hue envelop our planet's natural satellite.
|
|
Scientists think the moon — nicknamed MK20163 — is about 100 miles in diameter, but the exact details of this mysterious natural satellite are still a mystery.
|
|
From the Cassini team:This half-lit view of Enceladus bears a passing resemblance to similar views of Earth's own natural satellite, but the similarities end there.
|
|
But our natural satellite has no atmosphere to speak of, so celestial objects of various sizes are unimpeded, smashing into the lunar surface at tremendous speeds.
|
|
It's far too distant to be considered a true natural satellite of our planet, but it's a good example of a quasi-satellite, or near-Earth companion.
|
|
Bonus prizes will also be awarded for separate achievements, like getting to the original Apollo landing site where humans first set foot on our closest natural satellite.
|
|
It's official: We're going back to Saturn's moon Titan, the second largest moon in the solar system and the only known natural satellite with a dense atmosphere.
|
|
The U.S. Apollo program, NASA's forerunner to the effort at returning humans to Earth's natural satellite, tallied six manned missions to the moon from 1969 to 1972.
|
|
The full blood moon is also a supermoon, meaning that the natural satellite is at its closest point to Earth in its elliptical orbit during its full phase.
|
|
Both these landers, and the payloads they carry, could include startup-designed equipment and systems to pave the way for sustainable human occupation of our large natural satellite.
|
|
DART will crash into a moonlet (a small natural satellite) of near-Earth asteroid Didymos, that is comparable in size to an asteroid that could pose a threat.
|
|
At the end of the mission, JUICE will enter into the orbit of Ganymede, and become the first spacecraft to orbit a natural satellite other than the Earth's moon.
|
|
The moon will be at its full phase as the natural satellite reaches its closest point to Earth in its orbit (called perigee), making it a supermoon on November 14.
|
|
August 17, 2018 China is moving toward its goal of exploring an unseen part of Earth's natural satellite, and today's show leads off with an update on the country's plans.
|
|
For thousands of years, people had been forced to behold our natural satellite from afar, but Luna 22 at last proved that its hitherto virgin surface was within our grasp.
|
|
The tidal forces that Earth and the Moon exert on each other are causing our natural satellite to gradually distance itself from us, while also slowing down Earth's rotation ever so slightly.
|
|
But that small percentage translates to a thousands of miles in distance, and Petro says it should serve as a great excuse for people to go out and stare up our natural satellite.
|
|
The cultural responses to Earth's only natural satellite have ranged from the Japanese folkloric figure of a rabbit in the moon making mochi, to contemporary work like the "Moonwalk Machine" designed by Sputniko!
|
|
The goal of the mission, which is codenamed "Europa Clipper," is to find out whether the icy natural satellite orbiting Jupiter could sustain life, and also explore whether it might be colonizable or habitable.
|
|
The natural satellite doesn't move around Earth in a perfect circle, which means that occasionally the moon will hit full phase when it is at its closest point (perigee) or farthest point (apogee) from the planet.
|
|
It's an appropriately titled film because Cernan, who launched into space on three different high-stakes missions during the Gemini and Apollo programs, is the last human to have stepped foot on Earth's only natural satellite.
|
|
While the sight of a bright full Moon on a clear night has enraptured countless generations of human beings, these close-up visuals of the lunar surface provide a whole new perspective on Earth's natural satellite.
|
|
By a lucky coincidence, the China National Space Administration, the country's space agency, has just demonstrated, with the landing of its lunar probe Chang'e-4, that it can position equipment on that part of Earth's natural satellite.
|
|
And while it's not as spectacular of an event as a solar or lunar eclipse, it's as good of a reason as any to step outside Sunday night and get a close look at Earth's natural satellite.
|
|
However, due to tidal forces between our planet and the moon, the natural satellite slowly spirals away from Earth at a rate of about 1.5 inches (3.82 centimeters) per year, causing our planet to rotate more slowly around its axis.
|
|
It's been more than 40 years since humans have stepped foot on the moon, and while we often see photos of our natural satellite, this week we are going to explore images taken on the moon by the last people who were there.
|
|
Winner of Young Photogapher (Under 15): Lunar Reversal, Brendan DevineA truly innovative, high-contrast image of the Moon that's been inverted to bring out the intricate details of the rugged, lunar landscape that we often miss in more traditional shots of our natural satellite.
|
|
This week, the first-ever photographs of the dark side of the moon taken from the surface of the natural satellite, athletes and their tattoos are becoming a problem for video games, eating in the Stone Age, Trump as an evangelical Cyrus the Great, and more.
|
|
Bezos' plan, uncovered by The Washington Post via a draft proposal presented to NASA and Trump's administration, outlines Blue Origin's plan to create a cargo spacecraft destined for the Moon that would help it ferry supplies, experiments and even people to Earth's largest natural satellite by around July 2020.
|
|
NASA is in final preparation stages for its Artemis 1 Moon mission, which will be the first in its Artemis series of missions that intend to return an American man to the Moon, and bring an American woman to the surface of Earth's natural satellite for the first time.
|
|
The video features suitably spacey, chill post rock music, and it's hard not to feel pretty small watching Earth's natural satellite ascend into the heavens, glowing orange at first like the Sun, and then yellow like the big cheese wheel to which we humans have long compared it.
|
|
Half a century ago, astronauts aboard NASA's Apollo 8 mission become the first humans to leave low Earth orbit, traverse the 240,000 miles separating our planet from its moon, and loop around that natural satellite to look upon its forever-hidden far side (not dark side) with their own eyes.
|
|
Why it matters: Researchers have long been interested in figuring out exactly what's been going on in the interior of our Moon, and this new experiment — which is happening about 50 years after the lunar rock sample was collected — could help create a more complete picture of the history of our natural satellite.
|
|
XPrize's Founder and Executive Chairman, Peter H. Diamonds, as well as its CEO Marcus Shingles, penned the following statement explaining the state of the Google Lunar Xprize, as well as the impact it has had thus far – even if it fell short of its lofty goal of Earth's nearest natural satellite: After close consultation with our five finalist Google Lunar XPRIZE teams over the past several months, we have concluded that no team will make a launch attempt to reach the Moon by the March 31st, 2018 deadline.
|
|
For instance in astronomical terminology a distinction may be drawn between a moon, any natural satellite, and the Moon, the natural satellite of Earth.
|
|
Dilmun is a region of high albedo on Titan, Saturn's natural satellite.
|
|
Sinlap is a circular depression on Titan, a natural satellite of Saturn.
|
|
Perkunas Virgae is a streak of colour on Titan, the natural satellite of Saturn.
|
|
'Eupheme , also Jupiter LX, originally known as ', is an outer natural satellite of Jupiter, 2 km in diameter.
|
|
Because of this shift in meaning, the term moon, which had continued to be used in a generic sense in works of popular science and in fiction, has regained respectability and is now used interchangeably with natural satellite, even in scientific articles. When it is necessary to avoid both the ambiguity of confusion with Earth's natural satellite the Moon and the natural satellites of the other planets on the one hand, and artificial satellites on the other, the term natural satellite (using "natural" in a sense opposed to "artificial") is used. To further avoid ambiguity, the convention is to capitalize the word Moon when referring to Earth's natural satellite, but not when referring to other natural satellites. Many authors define "satellite" or "natural satellite" as orbiting some planet or minor planet, synonymous with "moon" – by such a definition all natural satellites are moons, but Earth and other planets are not satellites.
|
|
Some astrobiologists, such as Dirk Schulze-Makuch, estimated that a sufficiently massive natural satellite may form a habitable moon similar to Earth.
|
|
Pandia , also known as Jupiter LXV, originally known as S/2017 J 4, is an outer natural satellite of Jupiter, 3 km in diameter.
|
|
Natural satellite systems, particularly those involving multiple planetary mass objects can have complex interactions which can have effects on multiple bodies or across the wider system.
|
|
Aegaeon , or ' (provisional designation '), is a natural satellite of Saturn. It is thought to be similarly smooth as Methone. It orbits between Janus and Mimas within Saturn's G Ring.
|
|
In astronomy, an irregular moon, irregular satellite or irregular natural satellite is a natural satellite following a distant, inclined, and often eccentric and retrograde orbit. They have been captured by their parent planet, unlike regular satellites, which formed in orbit around them. Irregular moons have a stable orbit, unlike temporary satellites which often have similarly irregular orbits but will eventually depart. As of October 2019, 145 irregular moons are known, orbiting all four of the outer planets (Jupiter, Saturn, Uranus and Neptune).
|
|
Narvi or Saturn XXXI is a natural satellite of Saturn. It was discovered by a team of astronomers led by Scott S. Sheppard in 2003, and given the temporary designation S/2003 S 1\.
|
|
The conditions of habitability for natural satellites are similar to those of planetary habitability. However, there are several factors which differentiate natural satellite habitability and additionally extend their habitability outside the planetary habitable zone.
|
|
Methone is a very small natural satellite of Saturn orbiting between the orbits of Mimas and Enceladus. It was discovered in 2004, and in 2012 was imaged more closely by the Cassini orbiter probe.
|
|
Dar Sai is a fictional planet referenced in author Jack Vance's fourth "Demon Princes" novel, The Face. It is a desert planet orbiting the fictional star Cora, with a single large natural satellite called Mirrasou.
|
|
'Pallene is a very small natural satellite of Saturn. It is one of three small moons known as the Alkyonides that lie between the orbits of the larger Mimas and Enceladus. It is also designated '.
|
|
The tug of war in astronomy is the ratio of planetary and solar attractions on a natural satellite. The term was coined by Isaac Asimov in The Magazine of Fantasy and Science Fiction in 1963.
|
|
The discovery of 243 Ida's natural satellite Dactyl in the early 1990s confirmed that some asteroids have natural satellites; indeed, 87 Sylvia has two. Some, such as 90 Antiope, are double asteroids with two comparably sized components.
|
|
The Trabant was the result of a planning process which had been intended to design a three-wheeled motorcycle. In German, Trabant is an astronomical term for a moon (or other natural satellite) of a celestial body.
|
|
Kenneth R. Lang. "The Cambridge Guide to the Solar System". 2011\. p. 15. quote: "Any object that orbits a planet is now called a satellite, and a natural satellite is also now called a moon." Therese Encrenaz, et al.
|
|
With a rotation period around 22 hours, Gonggong rotates slowly compared to other trans-Neptunian objects, which typically have periods less than 12 hours. The slow rotation of Gonggong may have been caused by tidal forces from its natural satellite, named Xiangliu.
|
|
The municipality Larissa has an area of , the municipal unit Larissa has an area of , and the community Larissa has an area of . The Larissa Chasma, a deep gash in the surface of Dione, a natural satellite of Saturn, was named after Larissa.
|
|
'Jupiter LXXII, originally known as ', is a natural satellite of Jupiter. It was discovered by Scott Sheppard in 2011.MPEC 2012-B97 : S/2011 J 1 AND S/2011 J 2 2012 Jan. 29 (issued)Jupiter's Known Satellites It belongs to the Carme group.
|
|
Most regular moons (natural satellites following relatively close and prograde orbits with small orbital inclination and eccentricity) in the Solar System are tidally locked to their respective primaries, meaning that the same side of the natural satellite always faces its planet. The only known exception is Saturn's natural satellite Hyperion, which rotates chaotically because of the gravitational influence of Titan. In contrast, the outer natural satellites of the giant planets (irregular satellites) are too far away to have become locked. For example, Jupiter's Himalia, Saturn's Phoebe, and Neptune's Nereid have rotation periods in the range of ten hours, whereas their orbital periods are hundreds of days.
|
|
In astronomy, an inner moon or inner natural satellite is a natural satellite following a prograde, low-inclination orbit inwards of the large satellites of the parent planet. They are generally thought to have been formed in situ at the same time as the coalescence of the original planet. Neptune's moons are an exception, as they are likely reaggregates of the pieces of the original bodies, which were disrupted after the capture of the large moon Triton. Inner satellites are distinguished from other regular satellites by their proximity to the parent planet, their short orbital periods (usually under a day), their low mass, small size, and irregular shapes.
|
|
During season 2 of the 1987 cartoon series, the Technodrome is located on a rocky landscape, on an unnamed planet or natural satellite in Dimension X. A similar place is also seen in the early season 2 adaptions and some following issues of the Archie comics.
|
|
Huya has one known natural satellite, designated S/2012 (38628) 1. The satellite is relatively large compared to Huya and is expected to have slowed its rotation, although measurements of Huya's brightness variations have indicated that Huya's rotation may not be synchronous with the satellite's orbit.
|
|
A natural satellite was reported to be orbiting on February 27, 2007. It is estimated to be from the primary, with an orbital period of days, an eccentricity of and an inclination of . Assuming similar albedos, it is a quarter the diameter of its primary, or around in diameter.
|
|
Suttungr , or Saturn XXIII, is a natural satellite of Saturn. It was discovered by Brett J. Gladman, et al. in 2000, and given the temporary designation S/2000 S 12\. It was named for Suttungr in Norse mythology, a Jötunn or giant who once owned the mead of poetry.
|
|
On November 28, 2011, a natural satellite of 5261 Eureka was found. It has yet to be named, and its provisional designation is S/2011 (5261) 1. The moon is about 0.46 km in diameter and orbits 2.1 km from Eureka. The satellite's existence was announced in September 2014.
|
|
Styx is a small natural satellite of Pluto whose discovery was announced on 11 July 2012. As of 2020, it is the smallest known moon of Pluto. It was imaged along with Pluto and Pluto's other moons by the New Horizons spacecraft in July 2015. A single image was returned.
|
|
It was the second asteroid visited by a spacecraft and the first found to have a natural satellite. Ida's orbit lies between the planets Mars and Jupiter, like all main-belt asteroids. Its orbital period is 4.84 years, and its rotation period is 4.63 hours. Ida has an average diameter of .
|
|
'Jupiter LII, originally known as ', is a natural satellite of Jupiter. It was discovered by Christian Veillet in 2010.MPEC 2011-L06: S/2010 J 1 and S/2010 J 2 June 1, 2011 (discovery) It received its permanent number in March 2015.CBET "4075: 20150307: Satellites of Jupiter", March 7, 2015.
|
|
Anthe is a very small natural satellite of Saturn lying between the orbits of Mimas and Enceladus. It is also known as Saturn XLIX; its provisional designation was S/2007 S 4. It is named after one of the Alkyonides; the name means flowery. It is the sixtieth confirmed moon of Saturn.
|
|
"The Solar System". 2004\. p. 30. Tilman Spohn, Doris Breuer, Torrence Johnson. "Encyclopedia of the Solar System". 2014\. p. 18. A few recent authors define "moon" as "a satellite of a planet or minor planet", and "planet" as "a satellite of a star" – such authors consider Earth as a "natural satellite of the Sun".
|
|
'Jupiter LVI, provisionally known as ', is a natural satellite of Jupiter. It was discovered by Scott Sheppard in 2011.MPEC 2012-B97 : S/2011 J 1 AND S/2011 J 2 2012 Jan. 29 (discovery)Jupiter's Known Satellites Images of the newly discovered moon were captured using the Magellan-Baade telescope at the Las Campanas Observatory in Chile.
|
|
Hydra is a natural satellite of Pluto, with a diameter of approximately across its longest dimension. It is the second largest moon of Pluto, being slightly larger than Nix. Hydra was discovered along with Nix by the Pluto Companion Search Team in June 2005. It was named after the Hydra, the nine-headed underworld serpent in Greek mythology.
|
|
Moonbase Alpha is a video game that provides a realistic simulation of life on a natural satellite based on potential Moon base programs. It was made by the Army Game Studio, developers of America's Army, and Virtual Heroes, Inc. in conjunction with NASA Learning Technologies. The game was released on July 6, 2010, as a free download on Steam.
|
|
Thrymr , or Saturn XXX, is a natural satellite of Saturn. It was discovered by Gladman and colleagues in 2000, and given the temporary designation S/2000 S 7\. Its name comes from Norse mythology, where Thrymr is a Jotun. Thrymr is about 7 kilometres in diameter, and orbits Saturn at an average distance of 20,810 Mm in 1120.809 days.
|
|
Francesco Fontana's drawing of the supposed satellite(s) of Venus. Woodcuts from Fontana's work (1646). The fringes of light around Venus are produced by optical effects Neith is a hypothetical natural satellite of Venus reportedly sighted by Giovanni Cassini in 1672 and by several other astronomers in following years. The first supposed sighting of this moon was in 1650.
|
|
Nix is a natural satellite of Pluto, with a diameter of across its longest dimension. It was discovered along with Pluto's outermost moon Hydra on 15 June 2005 by the Pluto Companion Search Team. It was named after Nyx, the Greek goddess of the night. Nix is the third moon of Pluto by distance, orbiting between the moons Styx and Kerberos.
|
|
Mercury (0.596), Venus (0.444), Earth (1.00) and Mars (0.697). Sizes to scale. The Earth Similarity Index (ESI) is a proposed characterization of how similar a planetary-mass object or natural satellite is to Earth. It was designed to be a scale from zero to one, with Earth having a value of one; this is meant to simplify planet comparisons from large databases.
|
|
An orbiting body may be a spacecraft (i.e. an artificial satellite) or a natural satellite, such as a planet, dwarf planet, moon, moonlet, asteroid, or comet. A system of two orbiting bodies is modeled by the Two-Body Problem and a system of three orbiting bodies is modeled by the Three-Body Problem. These problems can be generalized to an N-body problem.
|
|
The following outline is provided as an overview of and topical guide to the Moon: Moon - Earth's only permanent natural satellite. It is one of the largest natural satellites in the Solar System, and the largest among planetary satellites relative to the size of the planet that it orbits (its primary). It is the second-densest satellite among those whose densities are known (after Jupiter's satellite Io).
|
|
The following outline is provided as an overview of and topical guide to Venus: Venus - second planet from the Sun, orbiting it every 224.7 Earth days. It has the longest rotation period (243 days) of any planet in the Solar System and rotates in the opposite direction to most other planets. It has no natural satellite. It is named after the Roman goddess of love and beauty.
|
|
Artist's concept of exomoon alt= A subsatellite, also known as a submoon or moonmoon, is a natural or artificial satellite that orbits a natural satellite, i.e. a "moon of a moon". It is inferred from the empirical study of natural satellites in the Solar System that subsatellites may be elements of planetary systems. In the Solar System, the giant planets have large collections of natural satellites.
|
|
'Jupiter LI, provisionally known as ', is a natural satellite of Jupiter. It was discovered by R. Jacobson, M. Brozović, B. Gladman, and M. Alexandersen in 2010.MPEC 2011-L06: S/2010 J 1 and S/2010 J 2 2011 June 1 (discovery) IAUC 9222 Jupiter's Known Satellites It received its permanent number in March 2015.CBET 4075: 20150307 : SATELLITES OF JUPITER, 7 March 2015.
|
|
A picture of Earth and the Moon from Mars. The presence of the Moon (which has about 1/81 the mass of Earth), is slowing Earth's rotation and extending the day by about 2 milliseconds every 100 years. Tidal acceleration is an effect of the tidal forces between an orbiting natural satellite (e.g. the Moon), and the primary planet that it orbits (e.g. Earth).
|
|
The waxing gibbous Moon as viewed from Earth The Moon is the largest natural satellite of and the closest major astronomical object to Earth. The Moon may be observed by using a variety of optical instruments, ranging from the naked eye to large telescopes. The Moon is the only celestial body upon which surface features can be discerned with the unaided eyes of most people.
|
|
Irregular satellites of Neptune Neso , also known as Neptune XIII, is the outermost known natural satellite of Neptune. It is an irregular moon discovered by Matthew J. Holman, Brett J. Gladman, et al. on August 14, 2002, though it went unnoticed until 2003. Neso orbits Neptune at a distance of more than 48 Gm (million km), making it (as of 2015) the most distant known moon of any planet.
|
|
A hypothetical Solar System object is a planet, natural satellite, subsatellite or similar body in the Solar System whose existence is not known, but has been inferred from observational scientific evidence. Over the years a number of hypothetical planets have been proposed, and many have been disproved. However, even today there is scientific speculation about the possibility of planets yet unknown that may exist beyond the range of our current knowledge.
|
|
Kerberos is a small natural satellite of Pluto, about in its longest dimension. It was the fourth moon of Pluto to be discovered and its existence was announced on 20 July 2011. It was imaged, along with Pluto and its four other moons, by the New Horizons spacecraft in July 2015. The first image of Kerberos from the flyby was released to the public on 22 October 2015.
|
|
The discovery was announced in an IAU Circular notice published on 22 February 2007. Using observations with the Hubble Space Telescope from 13 November 2005, Michael Brown and T. A. Suer detected a natural satellite. The discovery of a satellite of Orcus was reported in an IAU Circular notice published on 22 February 2007. The satellite was given the designation S/2005 (90482) 1 before later being named Vanth.
|
|
A natural satellite, or moon, is, in the most common usage, an astronomical body that orbits a planet or minor planet (or sometimes another small Solar System body). In the Solar System, there are six planetary satellite systems containing 205 known natural satellites. Four IAU-listed dwarf planets are also known to have natural satellites: Pluto, Haumea, Makemake, and Eris. , there are 334 other minor planets known to have moons.
|
|
'Philophrosyne ( or ), also Jupiter LVIII and provisionally known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard, et al. in 2003,IAUC 8116: Satellites of Jupiter and Saturn 2003 April (discovery)MPEC 2003-G17: S/2003 J 15 2003 April (discovery and ephemeris) but then lost. It was recovered in 2017 and given its permanent designation that year.
|
|
'Amalthea is a moon of Jupiter. It has the third closest orbit around Jupiter among known moons and was the fifth moon of Jupiter to be discovered, so it is also known as '. Edward Emerson Barnard discovered the moon on 9 September 1892 and named it after Amalthea of Greek mythology. It was the last natural satellite to be discovered by direct visual observation; all later moons were discovered by photographic or digital imaging.
|
|
Jupiter LIV, originally known as S/2016 J 1, is an outer natural satellite of Jupiter. It was discovered by Scott S. Sheppard in 2016, but not announced until June 2, 2017 via a Minor Planet Electronic Circular from the Minor Planet Center. It is about 1 kilometer in diameter and orbits at a semi-major axis of about 20,650,845 km with an inclination of about 139.8°. It belongs to the Ananke group.
|
|
Pirx is a 90 km (55.9 miles) wide impact crater on Pluto's natural satellite Charon, discovered in 2015 by the American New Horizons probe. It is located in at . The crater is located near Charon's north pole. Crater Pirx is named after the main character in a series of short stories by Stanislaw Lem, who travels between the Earth, Moon and Mars; this name was approved by the International Astronomical Union in 2018.
|
|
The International Space Station orbits Earth once about every 92 minutes, flying at about above sea level. Two bodies of different masses orbiting a common barycenter. The relative sizes and type of orbit are similar to the Pluto–Charon system. In physics, an orbit is the gravitationally curved trajectory of an object,orbit (astronomy) – Britannica Online Encyclopedia such as the trajectory of a planet around a star or a natural satellite around a planet.
|
|
Mundilfari, or Saturn XXV, is a natural satellite of Saturn. It was discovered by Brett J. Gladman, et al. in 2000, and given the temporary designation S/2000 S 9\. Mundilfari is about 7 kilometres in diameter, and orbits Saturn at an average distance of 18,360 Mm in 928.806 days, at an inclination of 170° to the ecliptic (150° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.198.
|
|
Ersa , also Jupiter LXXI, originally known as S/2018 J 1, is an outer natural satellite of Jupiter. It was discovered by Scott S. Sheppard and his team on 11 May 2018, and was later announced on 17 July 2018, via a Minor Planet Electronic Circular from the Minor Planet Center. It is about in diameter and has an orbit radius of around ; its orbital inclination is about 30.61°. It belongs to the Himalia group.
|
|
Kalliope has one known natural satellite, called Linus or (22) Kalliope I Linus. It is quite large about 28 km in diameter and would be a sizeable asteroid by itself. It orbits about 1100 km from the center of Kalliope, equivalent to about 13.2 Kalliope radii. Linus was discovered on 29 August 2001 by Jean-Luc Margot and Michael E. Brown, while another team led by William Merline also independently detected the moon 3 days later.
|
|
The atmosphere of Titan is the layer of gases surrounding Titan, the largest moon of Saturn. It is the only thick atmosphere of a natural satellite in the Solar System. Titan's lower atmosphere is primarily composed of nitrogen (94.2%), methane (5.65%), and hydrogen (0.099%). There are trace amounts of other hydrocarbons, such as ethane, diacetylene, methylacetylene, acetylene, propane, PAHs and of other gases, such as cyanoacetylene, hydrogen cyanide, carbon dioxide, carbon monoxide, cyanogen, acetonitrile, argon and helium.
|
|
An exomoon or extrasolar moon is a natural satellite that orbits an exoplanet or other non-stellar extrasolar body. It is inferred from the empirical study of natural satellites in the Solar System that they are likely to be common elements of planetary systems. The majority of detected exoplanets are giant planets. In the Solar System, the giant planets have large collections of natural satellites (see Moons of Jupiter, Moons of Saturn, Moons of Uranus and Moons of Neptune).
|
|
Europa, a potentially habitable moon of Jupiter. The habitability of natural satellites is a measure of the potential of natural satellites to have environments hospitable to life. Habitable environments do not necessarily harbor life. Natural satellite habitability is an emerging field which is considered important to astrobiology for several reasons, foremost being that natural satellites are predicted to greatly outnumber planets and it is hypothesized that habitability factors are likely to be similar to those of planets.
|
|
Titan is the largest moon of Saturn and the second-largest natural satellite in the Solar System. It is the only moon known to have a dense atmosphere, and the only known body in space, other than Earth, where clear evidence of stable bodies of surface liquid has been found. Titan is the sixth gravitationally rounded moon from Saturn. Frequently described as a planet-like moon, Titan is 50% larger (in diameter) than Earth's moon and 80% more massive.
|
|
Several astronomers have considered Ixion to be a possible dwarf planet under the expectation that it is large enough to have assumed a round shape under hydrostatic equilibrium, although studies in 2019 suggest that objects around the size of Ixion may retain significant internal porosity and thus represent a transitional zone between small Solar System bodies and dwarf planets. Ixion is currently not known to have a natural satellite; thus its mass and density remain unknown.
|
|
Earth's outer layer is divided into several rigid tectonic plates that migrate across the surface over many millions of years. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates Earth's magnetic field, and a convecting mantle that drives plate tectonics. Earth's gravity interacts with other objects in space, especially the Sun and the Moon, which is Earth's only natural satellite. Earth orbits around the Sun in about 365.25 days.
|
|
Size comparisons: Earth, the Moon, and Charon Charon's diameter is , just over half that of Pluto. Larger than the dwarf planet Ceres, it is the twelfth largest natural satellite in the Solar System. Charon's slow rotation means that there should be little flattening or tidal distortion, if Charon is sufficiently massive to be in hydrostatic equilibrium. Any deviation from a perfect sphere is too small to have been detected by observations by the New Horizons mission.
|
|
The relative sizes of Deimos and Phobos as seen from the surface of Mars, compared to the relative size in the sky of the Moon as seen from Earth Orbits of Phobos and Deimos. Phobos makes about four orbits for every one made by Deimos. The orbital motion of Phobos has been intensively studied, making it "the best studied natural satellite in the Solar System" in terms of orbits completed. Its close orbit around Mars produces some unusual effects.
|
|
Rhea's proposed rings No "moons of moons" or subsatellites (natural satellites that orbit a natural satellite of a planet) are currently known. In most cases, the tidal effects of the planet would make such a system unstable. However, calculations performed after the recent detection of a possible ring system around Saturn's moon Rhea indicate that satellites orbiting Rhea could have stable orbits. Furthermore, the suspected rings are thought to be narrow, a phenomenon normally associated with shepherd moons.
|
|
Surtur or Saturn XLVIII (provisional designation S/2006 S 7) is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on June 26, 2006 from observations taken between January and April 2006. It was named after Surt, a leader of the fire giants of Norse mythology. Surtur is about 6 kilometres in diameter, and orbits Saturn at an average distance of 22,243.6 Mm in 1238.575 days.
|
|
Fobos-Grunt, a sample return mission to Mars' natural satellite Phobos, would have carried the first Chinese planetary probe, Yinghuo-1. Several flybys occurred in 2009, with Cassini continuing to orbit Saturn, passing close to a number of its natural satellites. In February, Dawn passed within of Mars, during a gravity assist manoeuvre for its journey to the asteroid belt. In September, MESSENGER made its third and final flyby of Mercury before entering orbit in 2011.
|
|
2012 Asteroid capture by Keck Institute for Space Studies for Asteroid Redirect Mission Asteroid capture is the entering by an asteroid into an orbit around a larger planetary body. The larger body is said to have "captured" the asteroid, which thereafter is its natural satellite. Typically, asteroids that approach close to a planet are either thrown out into space or else hit the planet. However, occasionally the asteroid is captured in an orbit around the planet.
|
|
Jupiter LXIII, provisionally known as S/2017 J 2, is an outer natural satellite of Jupiter. It was discovered by Scott S. Sheppard and his team in 2017, but not announced until July 17, 2018 via a Minor Planet Electronic Circular from the Minor Planet Center. It is about 2 kilometers in diameter and orbits at a semi-major axis of about 23,303,000 km with an inclination of about 166.4°. It belongs to the Carme group.
|
|
Jupiter LXIV, originally known as S/2017 J 3, is an outer natural satellite of Jupiter. It was discovered by Scott S. Sheppard and his team in 2017, but not announced until July 17, 2018 via a Minor Planet Electronic Circular from the Minor Planet Center. It is about 2 kilometers in diameter and orbits at a semi-major axis of about 20,694,000 km with an inclination of about 147.9°. It belongs to the Ananke group.
|
|
Jupiter LXVI, originally known as S/2017 J 5, is an outer natural satellite of Jupiter. It was discovered by Scott S. Sheppard and his team in 2017, but not announced until July 17, 2018 via a Minor Planet Electronic Circular from the Minor Planet Center. It is about 2 kilometers in diameter and orbits at a semi-major axis of about 23,232,000 km with an inclination of about 164.3°. It belongs to the Carme group.
|
|
Jupiter LXVII, originally known as S/2017 J 6, is an outer natural satellite of Jupiter. It was discovered by Scott S. Sheppard and his team in 2017, but not announced until July 17, 2018, via a Minor Planet Electronic Circular from the Minor Planet Center. It is about 2 kilometers in diameter and orbits at a semi-major axis of about 22,455,000 km with an inclination of about 155.2°. It belongs to the Pasiphae group.
|
|
Jupiter LXVIII, provisionally known as S/2017 J 7, is an outer natural satellite of Jupiter. It was discovered by Scott S. Sheppard and his team in 2017, but not announced until July 17, 2018, via a Minor Planet Electronic Circular from the Minor Planet Center. It is about 2 kilometers in diameter and orbits at a semi-major axis of about 20,627,000 km with an inclination of about 143.4°. It belongs to the Ananke group.
|
|
Jupiter LXX, originally known as S/2017 J 9, is an outer natural satellite of Jupiter. It was discovered by Scott S. Sheppard and his team in 2017, but not announced until July 17, 2018, via a Minor Planet Electronic Circular from the Minor Planet Center. It is about 3 kilometers in diameter and orbits at a semi-major axis of about 21,487,000 km with an inclination of about 152.7°. It belongs to the Ananke group.
|
|
Jupiter LXIX, originally known as S/2017 J 8, is an outer natural satellite of Jupiter. It was discovered by Scott S. Sheppard and his team in 2017, but not announced until July 17, 2018, via a Minor Planet Electronic Circular from the Minor Planet Center. It is about 1 kilometer in diameter and orbits at a semi- major axis of about 23,232,700 km with an inclination of about 164.7°. It belongs to the Carme group.
|
|
By using the polarization of light, it is possible to detect an atmosphere around a planet or natural satellite. In 1950, most scientists thought that Mercury, because of its small size, had probably lost its atmosphere due to molecular escape into space. Dollfus announced that he had detected a very small atmosphere, again using polarization measurements made at the Pic du Midi Observatory in the French Pyrenees. His discovery contradicted the previous theoretical predictions based on the kinetic theory of gases.
|
|
The Moon is a gravity rounded astronomical body orbiting Earth and is the planet's only natural satellite. It is the fifth-largest satellite in the Solar System, and by far the largest among planetary satellites relative to the size of the planet that it orbits. The Moon is, after Jupiter's satellite Io, the second-densest satellite in the Solar System among those whose densities are known. The Moon is thought to have formed about 4.51 billion years ago, not long after Earth.
|
|
S/2004 S 31 is a natural satellite of Saturn and a member of the Inuit group. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 8, 2019 from observations taken between December 12, 2004 and March 22, 2007. S/2004 S 31 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 17,568 Gm in 869.65 days, at an inclination of 48.8° to the ecliptic, with an eccentricity of 0.240.
|
|
S/2004 S 32 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 8, 2019 from observations taken between December 12, 2004 and January 19, 2007. S/2004 S 32 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 21,214 Gm in 1153.96 days, at an inclination of 159° to the ecliptic, in a retrograde direction and with an eccentricity of 0.251.
|
|
S/2004 S 33 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 8, 2019 from observations taken between December 12, 2004 and March 22, 2007. S/2004 S 33 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 24,168 Gm in 1403.18 days, at an inclination of 160° to the ecliptic, in a retrograde direction and with an eccentricity of 0.399.
|
|
S/2004 S 34 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 8, 2019 from observations taken between December 12, 2004 and March 21, 2007. S/2004 S 34 is about 3 kilometres in diameter, and orbits Saturn at an average distance of 24,299 Gm in 1414.59 days, at an inclination of 166° to the ecliptic, in a retrograde direction and with an eccentricity of 0.235.
|
|
S/2004 S 35 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 8, 2019 from observations taken between December 12, 2004 and February 25, 2006. S/2004 S 35 is about 5 kilometres in diameter, and orbits Saturn at an average distance of 22,412 Gm in 1253.08 days, at an inclination of 177° to the ecliptic, in a retrograde direction and with an eccentricity of 0.194.
|
|
S/2004 S 37 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 8, 2019 from observations taken between December 12, 2004 and February 2, 2006. S/2004 S 37 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 15,892 Gm in 748.18 days, at an inclination of 163° to the ecliptic, in a retrograde direction and with an eccentricity of 0.497.
|
|
S/2004 S 38 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 8, 2019 from observations taken between December 12, 2004 and March 22, 2007. S/2004 S 38 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 21,908 Gm in 1211.02 days, at an inclination of 154° to the ecliptic, in a retrograde direction and with an eccentricity of 0.437.
|
|
S/2004 S 39 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 8, 2019 from observations taken between December 12, 2004 and March 21, 2007. S/2004 S 39 is about 3 kilometres in diameter, and orbits Saturn at an average distance of 23.575 Gm in 1351.83 days, at an inclination of 167° to the ecliptic, in a retrograde direction and with an eccentricity of 0.080.
|
|
' (also written 2013 BS45) is a horseshoe companion to the Earth like 3753 Cruithne. Like Cruithne, it does not orbit the Earth in the normal sense and at times it is on the other side of the Sun, yet it still periodically comes nearer to the Earth in sort of halo orbit before again drifting away. While not a traditional natural satellite, it does not quite have normal heliocentric orbit either and these are sometimes called quasi-satellties or horseshoe orbits.
|
|
S/2004 S 20 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and March 22, 2007. S/2004 S 20 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 19,418 Gm in 1010.55 days, at an inclination of 163° to the ecliptic, in a retrograde direction and with an eccentricity of 0.197.
|
|
S/2004 S 21 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and January 17, 2007. S/2004 S 21 is about 3 kilometres in diameter, and orbits Saturn at an average distance of 22,645 Gm in 1272.61 days, at an inclination of 160° to the ecliptic, in a retrograde direction and with an eccentricity of 0.318.
|
|
S/2004 S 22 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and February 1, 2006. S/2004 S 22 is about 3 kilometres in diameter, and orbits Saturn at an average distance of 20,636 Gm in 1107.13 days, at an inclination of 177° to the ecliptic, in a retrograde direction and with an eccentricity of 0.251.
|
|
S/2004 S 23 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and March 22, 2007. S/2004 S 23 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 21,163 Gm in 1149.82 days, at an inclination of 177° to the ecliptic, in a retrograde direction and with an eccentricity of 0.373.
|
|
S/2004 S 27 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and March 21, 2007. S/2004 S 27 is about 6 kilometres in diameter, and orbits Saturn at an average distance of 19,976 Gm in 1054.45 days, at an inclination of 168° to the ecliptic, in a retrograde direction and with an eccentricity of 0.122.
|
|
S/2004 S 28 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and March 21, 2007. S/2004 S 28 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 22,020 Gm in 1220.31 days, at an inclination of 170° to the ecliptic, in a retrograde direction and with an eccentricity of 0.143.
|
|
S/2004 S 29 is a natural satellite of Saturn and a member of the Inuit group. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and January 17, 2007. S/2004 S 29 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 16,981 Gm in 826.44 days, at an inclination of 45.1° to the ecliptic, with an eccentricity of 0.440.
|
|
S/2004 S 25 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and March 22, 2007. S/2004 S 25 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 21,174 Gm in 1150.69 days, at an inclination of 173° to the ecliptic, in a retrograde direction and with an eccentricity of 0.442.
|
|
Rainfalls of diamonds have been suggested to occur on the gas giant planets, Jupiter and Saturn, as well as on the ice giant planets, Uranus and Neptune. There is likely to be rain of various compositions in the upper atmospheres of the gas giants, as well as precipitation of liquid neon in the deep atmospheres. On Titan, Saturn's largest natural satellite, infrequent methane rain is thought to carve the moon's numerous surface channels. On Venus, sulfuric acid virga evaporates from the surface.
|
|
Polydeuces , or Saturn XXXIV, is a small natural satellite of Saturn that is co-orbital with the moon Dione and librates around its trailing Lagrangian point (). Its diameter is estimated to be 2–3 km. Dione's other co-orbital moon is Helene, which is bigger and located at the leading L4 point. Polydeuces was discovered by the Cassini Imaging Team on October 24, 2004, in images taken on October 21, 2004, and given the temporary designation S/2004 S 5\.
|
|
Sepharial became an influential author in the fields of the occult, astrology and numerology, and his writings had a considerable impact on Alfred H. Barley and Alan Leo, who he introduced to Theosophy. He can be credited as the first astrologer to use Waltemath earth's hypothetical natural satellite in his calculations. Since he considered it to be black enough to be invisible most of the time he call it "dark moon" Lilith.University of California " The Earth's Second Moon, 1846–present ". ().
|
|
Iapetus () is the third-largest natural satellite of Saturn, eleventh-largest in the Solar System,The moons more massive than Iapetus are: the Moon, the 4 Galilean moons (Ganymede, Callisto, Io, and Europa), Titan, Rhea, Titania, Oberon, and Triton. See JPLSSD. and the largest body in the Solar System known not to be in hydrostatic equilibrium. Discoveries by the Cassini mission in 2007 revealed several unusual features, such as a massive equatorial ridge running three-quarters of the way around the moon.
|
|
The internal structure of Earth In geology, the crust is the outermost solid shell of a rocky planet, dwarf planet, or natural satellite. It is usually distinguished from the underlying mantle by its chemical makeup; however, in the case of icy satellites, it may be distinguished based on its phase (solid crust vs. liquid mantle). The crusts of Earth, Mercury, Venus, Mars, Io, the Moon and other planetary bodies formed via igneous processes, and were later modified by erosion, impact cratering, volcanism, and sedimentation.
|
|
S/2004 S 36 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 8, 2019 from observations taken between December 12, 2004 and February 1, 2006. S/2004 S 36 is about 3 kilometres in diameter, and orbits Saturn at an average distance of 23,192 Gm in 1319.07 days, at an inclination of 155° to the ecliptic, in a retrograde direction and with an eccentricity of 0.748, the highest of any of Saturn's moons.
|
|
Diagram showing the five primary layers of the Earth's atmosphere: exosphere, thermosphere, mesosphere, stratosphere, and troposphere. The layers are to scale. From the Earth's surface to the top of the stratosphere (50km) is just under 1% of Earth's radius. The exosphere ( "outside, external, beyond", "sphere") is a thin, atmosphere-like volume surrounding a planet or natural satellite where molecules are gravitationally bound to that body, but where the density is too low for them to behave as a gas by colliding with each other.
|
|
The most famous of these is the video "Moonbase Alpha provides a realistic simulation of life on a natural satellite", in which has gained 8 million views as of November 2019. Certain "codes" can be entered in the chat to change the pitch, tone, and (or) length of the TTS to make it sing. This was propagated by a still active community, known for constantly saying phrases such as "aeiou", "John Madden" or even using the in built TTS function to make full length song parodies.
|
|
Its gravity is much higher than that of Earth, and its atmospheric composition is unsuitable for humans. It is also shown to have a natural satellite. Kryptonian society is divided into houses, such as the House of El. Citizens wear the crests of their house over their chests, which hold meanings, such as the crest of House of El meaning "hope". Kryptonian civilization is at least 100,000 years old and many millennia more advanced than human civilization on Earth, and had begun exploring the Milky Way Galaxy.
|
|
Geology (from the Ancient Greek γῆ, gē ("earth") and -λoγία, -logia, ("study of", "discourse")) is an Earth science concerned with the solid Earth, the rocks of which it is composed, and the processes by which they change over time. Geology can also include the study of the solid features of any terrestrial planet or natural satellite such as Mars or the Moon. Modern geology significantly overlaps all other Earth sciences, including hydrology and the atmospheric sciences, and so is treated as one major aspect of integrated Earth system science and planetary science.
|
|
'Jupiter LXI, provisionally known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers led by Brett J. Gladman, et al. in 2003.IAUC 8125: S/2003 J 19 and S/2003 J 20 2003 April (discovery)MPEC 2003-G64: S/2003 J 19 2003 April (discovery and ephemeris) is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 22,709 Mm in 699.125 days, at an inclination of 165° to the ecliptic (164° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.1961.
|
|
The spacecraft discovered Ida has a moon, Dactyl, the first discovery of a natural satellite orbiting an asteroid. In 1994, Galileo was perfectly positioned to watch the fragments of Comet Shoemaker–Levy 9 crash into Jupiter, whereas terrestrial telescopes had to wait to see the impact sites as they rotated into view. After releasing its atmospheric probe on July 13, 1995, the Galileo orbiter became the first artificial satellite of Jupiter at 01:16 UTC on December 8, 1995, after it fired its main engine to enter a 198-day parking orbit.
|
|
Triton is the largest natural satellite of the planet Neptune, and the first Neptunian moon to be discovered. The discovery was made on October 10, 1846, by English astronomer William Lassell. It is the only large moon in the Solar System with a retrograde orbit, an orbit in the direction opposite to its planet's rotation. At in diameter, it is the seventh-largest moon in the Solar System, the only satellite of Neptune massive enough to be in hydrostatic equilibrium and the second-largest planetary moon in relation to its primary, after Earth's Moon.
|
|
Hyperion, together with Pluto's moons Nix and Hydra, is among only a few moons in the Solar System known to rotate chaotically, although it is expected to be common in binary asteroids. It is also the only regular planetary natural satellite in the Solar System known not to be tidally locked. Hyperion is unique among the large moons in that it is very irregularly shaped, has a fairly eccentric orbit, and is near a much larger moon, Titan. These factors combine to restrict the set of conditions under which a stable rotation is possible.
|
|
8-cell embryo for transfer in in-vitro fertilization Embryo space colonization is a theoretical interstellar space colonization concept that involves sending a robotic mission to a habitable terrestrial planet, dwarf planet, minor planet or natural satellite transporting frozen early-stage human embryos or the technological or biological means to create human embryos. The proposal circumvents the most severe technological problems of other mainstream interstellar colonization concepts. In contrast to the sleeper ship proposal, it does not require the more technically challenging 'freezing' of fully developed humans (see cryonics).
|
|
However, when the Journal de Scavans reported Cassini's discovery of two new Saturnian moons in 1686, it referred to them strictly as "satellites", though sometimes to Saturn as the "primary planet". When William Herschel announced his discovery of two objects in orbit around Uranus in 1787, he referred to them as "satellites" and "secondary planets". All subsequent reports of natural satellite discoveries used the term "satellite" exclusively,See primary citations in Timeline of discovery of Solar System planets and their moons though the 1868 book Smith's Illustrated Astronomy referred to satellites as "secondary planets".
|
|
Located on an unnamed planet or natural satellite, the Dimension X Penitentiary is where some of the worst criminals of Dimension X are being held. Convicts include Skaarg, Dementor, and the Dregma Brothers. Unfortunately, the penitentiary is not protected against dimensional portals, allowing Skarg, Dementor, and the Dregma Brothers to slip out while Irma and Vernon Fenwick slip through the portal from the Earth to Dimension X, ending up there inside one of the holding cells. It was seen in the episode "Convicts from Dimension X" of the 1987–1996 series.
|
|
A map of the Moon from Andrees Allgemeiner Handatlas, 1st edition (1881), predating IAU conventions Planetary nomenclature, like terrestrial nomenclature, is a system of uniquely identifying features on the surface of a planet or natural satellite so that the features can be easily located, described, and discussed. Since the invention of the telescope, astronomers have given names to the surface features they have discerned, especially on the Moon and Mars. To standardize planetary nomenclature, the International Astronomical Union (IAU) was assigned in 1919 the task of selecting official names for features on Solar System bodies.
|
|
Orthosie , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2001, and given the temporary designation '. Orthosie is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 21,075,662 km in 625.07 days, at an inclination of 146.46° to the ecliptic (143° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.3376. It was named in August 2003 after Orthosie, the Greek goddess of prosperity and one of the Horae.
|
|
Kari or Saturn XLV is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on 26 June 2006 from observations taken between January and April 2006. Kari is about 7 kilometres in diameter, and orbits Saturn at an average distance of 22,305,100 km in 1243.71 days, at an inclination of 148.4° to the ecliptic (151.5° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.3405. The rotation period has been determined to be hours.
|
|
Greip or Saturn LI is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on 26 June 2006, from observations taken between 5 January and 1 May 2006. Greip is about 6 kilometres in diameter, and orbits Saturn at an average distance of 18,066 Mm in 906.556 days, at an inclination of 172.7° to the ecliptic (159.2° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.3735. Its rotation period is hours.
|
|
Loge or Saturn XLVI is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on 26 June 2006, from observations taken between January and April 2006. Loge is about 6 kilometres in diameter, and orbits Saturn at an average distance of 23,142.0 Mm in 1314.364 days, at an inclination of 166.5° to the ecliptic (165.3° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.1390. It has a rotation period of about hours.
|
|
Bergelmir or Saturn XXXVIII (provisional designation S/2004 S 15) is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on May 4, 2005, from observations taken between December 12, 2004, and March 9, 2005. Bergelmir is about in diameter, and orbits Saturn at an average distance of 19,372 Mm in 1006.659 days, at an inclination of 157° to the ecliptic (134° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.152. Its rotation period is hours.
|
|
Aegir, also Saturn XXXVI (provisional designation S/2004 S 10), is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on May 4, 2005, from observations taken between December 12, 2004, and March 11, 2005. Aegir is about 6 kilometres in diameter, and orbits Saturn at an average distance of 19,618 Mm in 1025.908 days, at an inclination of 167° to the ecliptic (140° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.237.
|
|
' is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard et al. in 2004 from pictures taken in 2003.IAUC 8281: S/2003 J 23 2004 February 4 (discovery)MPEC 2004-B81: S/2003 J 23 2004 January 31 (discovery and ephemeris) is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 22,740 Mm in 700.538 days, at an inclination of 149° to the ecliptic (149° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.3931.
|
|
The Moon is an exceptionally large natural satellite relative to Earth: Its diameter is more than a quarter and its mass is 1/81 of Earth's. It is the largest moon in the Solar System relative to the size of its planet, though Charon is larger relative to the dwarf planet Pluto, at 1/9 Pluto's mass. The Earth and the Moon's barycentre, their common center of mass, is located (about a quarter of Earth's radius) beneath Earth's surface. The Earth revolves around the Earth-Moon barycentre once a sidereal month, with 1/81 the speed of the Moon, or about per second.
|
|
S/2004 S 26 is the outermost known natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and March 21, 2007. S/2004 S 26 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 26,676 Gm (0.178 AU) in 1627.18 days (the only satellite known to take over 4 years to orbit Saturn), at an inclination of 171° to the ecliptic, in a retrograde direction and with an eccentricity of 0.165.
|
|
In the novel, Coyote is a natural satellite of Bear, the fourth planet of the 47 Ursae Majoris system, 46 light-years from Earth. It is settled by the crew and passengers of the URSS Alabama, a starship built by the authoritarian conservative United Republic of America but stolen just prior to its scheduled launch. The crew and passengers spend over two centuries in biostasis en route to Coyote, arriving in the system in the Gregorian year 2300. During the voyage, the crew enjoyed the benefits of relativistic velocities; for them, it is the year 2296.
|
|
Claims of the existence of other moons of Earth—that is, of one or more natural satellites with relatively stable orbits of Earth, other than the Moon—have existed for some time. Several candidates have been proposed, but none has been confirmed. Since the 19th century, scientists have made genuine searches for more moons, but the possibility has also been the subject of a number of dubious non-scientific speculations as well as a number of likely hoaxes. Although the Moon is Earth's only natural satellite, there are a number of near-Earth objects (NEOs) with orbits that are in resonance with Earth.
|
|
'Vanth, full designation ', is the single known natural satellite of the plutino and likely dwarf planet 90482 Orcus. With a diameter of about 440 km, it is half the size of Orcus and probably the third-largest known moon of a known trans-Neptunian object, after Pluto I Charon and Eris I Dysnomia, though it is possible that the poorly resolved Varda I Ilmarë or Haumea I Hiiaka might be comparable in size. Vanth was discovered by Michael Brown and T.-A. Suer using discovery images taken by the Hubble Space Telescope on 13 November 2005.
|
|
'Adrastea , also known as ', is the second by distance, and the smallest of the four inner moons of Jupiter. It was discovered in photographs taken by Voyager 2 in 1979, making it the first natural satellite to be discovered from images taken by an interplanetary spacecraft, rather than through a telescope. It was officially named after the mythological Adrasteia, foster mother of the Greek god Zeus—the equivalent of the Roman god Jupiter. Adrastea is one of the few moons in the Solar System known to orbit its planet in less than the length of that planet's day.
|
|
Fornjot or Saturn XLII is the second outermost natural satellite of Saturn (after S/2004 S 26). Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on 4 May 2005 from observations taken between 12 December 2004, and 11 March 2005. It is about 6 kilometres in diameter, and it orbits Saturn at an average distance of 23,609 Mm in 1354 at an inclination of 168° to the ecliptic (160° to Saturn's equator) in a retrograde direction and with an eccentricity of 0.186. It has an ambiguous rotation period of 7 or hours.
|
|
Hati or Saturn XLIII is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on 4 May 2005, from observations taken between 12 December 2004 and 11 March 2005. Hati is about 6 kilometers in diameter, and orbits Saturn at an average distance of 20,303 Mm in 1080 days, at an inclination of 163° to the ecliptic (165° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.291. In March 2013, the synodic rotational period was measured by Cassini to about hours.
|
|
It has a significantly eccentric orbit at 1.4 AU and either crosses the system's predicted habitable zone or lies within it though it does not fit the current models for planetary habitability due to its large mass (24 times Earth). If it is a gas giant, it is likely of Sudarsky Class II. There is a possibility that a natural satellite with sufficient atmospheric pressure could have liquid water on its surface. Its estimated orbital distance and eccentricity were downscaled in 2012 but remains in the habitable zone. The false detection probability is less than 0.1%.
|
|
S/2006 S 1 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on June 26, 2006 from observations taken between January 4 and April 30, 2006. S/2006 S 1 is about 6 kilometres in diameter, and orbits Saturn at an average distance of 18.65 Gm in 951.1 days, at an inclination of 154.6° to the ecliptic (178.9° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.0814. The moon was once considered lost in 2006 as it was not seen since its discovery.
|
|
S/2006 S 3 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on June 26, 2006 from observations taken between January and April 2006. S/2006 S 3 is about 6 kilometres in diameter, and orbits Saturn at an average distance of 21,308,400 km in 1160.7 days, at an inclination of 152.8° to the ecliptic, in a retrograde direction and with an eccentricity of 0.4707. The moon was once considered lost in 2006 as it was not seen since its discovery.
|
|
Jarnsaxa , also known as Saturn L (provisional designation S/2006 S 6), is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on June 26, 2006, from observations taken between January 5 and April 29, 2006. Jarnsaxa is about 6 kilometres in diameter, and orbits Saturn at an average distance of 18,556.9 Mm in 943.784 days, at an inclination of 162.9° to the ecliptic (164.1° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.1918. It is a member of the Norse group of irregular satellites.
|
|
Farbauti or Saturn XL is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on May 4, 2005, from observations taken between December 12, 2004, and March 9, 2005. Farbauti is about 5 kilometres in diameter, and orbits Saturn at an average distance of 20,291 Mm in 1079.099 days, at an inclination of 158° to the ecliptic (131° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.209. It was named in April 2007 after Fárbauti, a storm giant from Norse mythology, father of Loki.
|
|
S/2004 S 7 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on May 4, 2005 from observations taken between December 12, 2004 and March 8, 2005. S/2004 S 7 is about 6 kilometres in diameter, and orbits Saturn at an average distance of 20,999 Mm in 1140.24 days, at an inclination of 166° to the ecliptic (166° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.5299. This moon has not been seen since its discovery and is currently considered lost.
|
|
Bebhionn (pronounced or ), also known as Saturn XXXVII, is a small, irregular natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on 4 May 2005 from observations taken between 12 December 2004 and 9 March 2005. Bebhionn is about 6 kilometres in diameter and orbits Saturn at an average distance of 16,898 Mm in 820.130 days at an inclination of 41° to the ecliptic (18° to Saturn's equator) and with an eccentricity of 0.333. The rotation period of Bebhionn was measured at hours by the ISS camera of the Cassini spacecraft.
|
|
S/2004 S 17 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on May 4, 2005 from observations taken between December 13, 2004 and March 5, 2005. S/2004 S 17 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 19,099 Mm in 985.453 days, at an inclination of 167° to the ecliptic (162° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.226. This moon has not been seen since its discovery and is currently considered lost.
|
|
S/2004 S 13 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on 4 May 2005 from observations taken between 12 December 2004 and 9 March 2005. S/2004 S 13 is about 6 kilometres in diameter, and orbits Saturn at an average distance of 18,056 Mm in 905.848 days, at an inclination of 167° to the ecliptic (143° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.261. This moon has not been seen since its discovery in 2004 and is currently considered lost.
|
|
S/2004 S 12 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on May 4, 2005 from observations taken between December 12, 2004 and March 9, 2005. S/2004 S 12 is about 5 kilometres in diameter, and orbits Saturn at an average distance of 19.906 Gm in 1048.541 days, at an inclination of 164° to the ecliptic (162° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.396. This moon has not been seen since its discovery and is currently considered lost.
|
|
Artistic model of Salacia and Actaea's near circular orbit viewed at an angle Salacia has one natural satellite, Actaea, that orbits its primary every at a distance of and with an eccentricity of . It was discovered on 21 July 2006 by Keith Noll, Harold Levison, Denise Stephens and William Grundy with the Hubble Space Telescope. Actaea is magnitudes fainter than Salacia, implying a diameter ratio of 2.98 for equal albedos. Hence, assuming equal albedos, it has a diameter of Actaea has the same color as Salacia (V−I = and , respectively), supporting the assumption of equal albedos.
|
|
James McMahon is an American amateur astronomer, acknowledged for his visual observations of asteroid occultations. In 1978 his observation of the occultation of the asteroid 532 Herculina with the star SAO 120774, together with photometric study made at the Lowell Observatory, was considered a proof of the existence of a Herculina's natural satellite, which would be the first discovery of an asteroid moon in history. However, a 1993 Hubble Space Telescope observation failed to confirm the discovery. In 1979 James McMahon was the first person awarded with the newly established Amateur Achievement Award of the Astronomical Society of the Pacific.
|
|
The first natural satellite discovered using photographic plates was Phoebe in 1898. Pluto was discovered using photographic plates in a blink comparator; its moon Charon was discovered 48 years later in 1978 by U.S. Naval Observatory astronomer James W. Christy by carefully examining a bulge in Pluto's image on a photographic plate. Glass- backed plates, rather than film, were generally used in astronomy because they do not shrink or deform noticeably in the development process or under environmental changes. Several important applications of astrophotography, including astronomical spectroscopy and astrometry, continued using plates until digital imaging improved to the point where it could outmatch photographic results.
|
|
Prometheus (right) and Pandora (left) both orbit near Saturn's F ring, but only Prometheus is thought to act as a shepherd. Operation of a shepherd moon– particles are located in front or behind the Moon in its orbit, so these are either accelerated in the direction of the moon and thrown to the outside, or they are slowed on their path and pulled inwards. A shepherd moon (also herder moon, watcher moon) is a small natural satellite that clears a gap in planetary-ring material or keeps particles within a ring contained. The name is a result of the fact they limit the "herd" of the ring particles as a shepherd.
|
|
' is a natural satellite of Jupiter. It was discovered by a team of astronomers led by Brett J. Gladman in 2003.IAUC 8116: Satellites of Jupiter and Saturn 2003 April (discovery)MPEC 2003-G18: S/2003 J 16 2003 April (discovery and ephemeris) is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 20,744 Mm in 610.362 days, at an inclination of 151° to the ecliptic (149° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.3185. It belongs to the Ananke group, retrograde irregular moons which orbit Jupiter between 19.3 and 22.7 Gm, at inclinations of roughly 150°.
|
|
Herse , or Jupiter L', previously known by its provisional designation of ', is a natural satellite of Jupiter. It was discovered on 8 February 2003 by the astronomers Brett J. Gladman, John J. Kavelaars, Jean-Marc Petit, and Lynne Allen and also by a team of astronomers at the University of Hawaii.Daniel W. E. Green, IAUC 8116: Satellites of Jupiter and Saturn 2003 April 11 (discovery)Brian G. Marsden, MPEC 2003-G19: S/2003 J 17 2003 April 3 (discovery and ephemeris) It was named after Herse 'dew', by some accounts a daughter of Zeus and Selene the moon in Greek mythology,Keightley, p. 55; Hard, p.
|
|
Thelxinoe , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2004 from pictures taken in 2003, and originally received the temporary designation '. Thelxinoe is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 20,454 Mm in 597.607 days, at an inclination of 151° to the ecliptic (153° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.2685. It was named in March 2005 after Thelxinoe, one of the four original Muses according to some Greek writers, and a daughter of Zeus (Jupiter) by Mnemosyne.
|
|
In May 1955, Vallée first sighted an unidentified flying object over his Pontoise home. Six years later in 1961, while working on the staff of the French Space Committee, Vallée claims to have witnessed the destruction of the tracking tapes of an unknown object orbiting the earth. The particular object was a retrograde satellite – that is, a satellite orbiting the earth in the opposite direction to the earth's rotation. At the time he observed this, there were no rockets powerful enough to launch such a satellite, so the team was quite excited as they assumed that the Earth's gravity had captured a natural satellite (asteroid).
|
|
S/2004 S 30 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and March 21, 2007. S/2004 S 30 is about 4 kilometres in diameter, and orbits Saturn at an average distance of 20.396 Gm in 1087.84 days, at 157.5° to the ecliptic, in a retrograde direction and with an eccentricity of 0.113. Due to an error in the initial announcement of S/2004 S 30, it was announced by the Minor Planet Center with the exact same orbit as S/2004 S 25.
|
|
S/2004 S 24 is a natural satellite of Saturn, and the outermost known prograde satellite. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and March 22, 2007. S/2004 S 24 is about 3 kilometres in diameter, and orbits Saturn at an average distance of 22,901 Gm in 1294.25 days, at an inclination of 35.5° to the ecliptic, in a prograde direction and with an eccentricity of 0.085. Due to its inclination being similar to the four known members of the Gallic group, S/2004 S 24 could belong to the Gallic group.
|
|
When satellites or rings are first discovered, they are given provisional designations such as "" (the 11th new satellite of Jupiter discovered in 2000), "" (the first new satellite of Pluto discovered in 2005), or "" (the second new ring of Saturn discovered in 2004). The initial "S/" or "R/" stands for "satellite" or "ring", respectively, distinguishing the designation from the prefixes "C/", "D/", "P/", and "X/" used for comets. These designations are sometimes written as "", dropping the second space. The prefix "S/" indicates a natural satellite, and is followed by a year (using the year when the discovery image was acquired, not necessarily the date of discovery).
|
|
A planetary-mass moon is a planetary-mass object that is also a natural satellite. They are large and ellipsoidal (sometimes spherical) in shape. Two moons in the Solar System are larger than the planet Mercury (though less massive): Ganymede and Titan, and seven are larger and more massive than the dwarf planet . The concept of satellite planets – the idea that planetary-mass objects, including planetary-mass moons, are planets – is used by some planetary scientists, such as Alan Stern, who are more concerned with whether a celestial body has planetary geology (that is, whether it is a planetary body) than where it orbits (planetary dynamics).
|
|
Euporie , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2001, and given the temporary designation '. Euporie is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 19,088 Mm in 538.780 days, at an inclination of 145° to the ecliptic (145° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.144. It was named in August 2003 after Euporie, a Greek goddess of abundance and one of the Horae in Greek mythology (and thus a daughter of Zeus).
|
|
The first known natural satellite was the Moon, but it was considered a "planet" until Copernicus' introduction of De revolutionibus orbium coelestium in 1543. Until the discovery of the Galilean satellites in 1610 there was no opportunity for referring to such objects as a class. Galileo chose to refer to his discoveries as Planetæ ("planets"), but later discoverers chose other terms to distinguish them from the objects they orbited. The first to use the term satellite to describe orbiting bodies was the German astronomer Johannes Kepler in his pamphlet Narratio de Observatis a se quatuor Iouis satellitibus erronibus ("Narration About Four Satellites of Jupiter Observed") in 1610.
|
|
Fenrir , or Saturn XLI (provisional designation S/2004 S 16), is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on May 4, 2005, from observations taken between December 13, 2004, and March 5, 2005. Fenrir has an apparent magnitude of 25, making it one of the faintest known moons in the Solar System, and was discovered using some of the largest telescopes in the world. It is even too dark to be observed by the Cassini spacecraft in orbit around Saturn, for which it never gets brighter than approximately 17th apparent magnitude.
|
|
Hyrrokkin or Saturn XLIV is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on June 26, 2006, from observations taken between December 12, 2004, and April 30, 2006. Hyrrokkin is about 8 kilometres in diameter, and orbits Saturn at an average distance of 18,168 Mm in 914 days, at an inclination of 153° to the ecliptic (154° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.36. During four observations in March 2013, the synodic rotational period was measured by the Cassini spacecraft to approximately 12 hours and 45 minutes.
|
|
Ilmarë,Stressed on the first syllable or Varda I', full designation ', is the single known natural satellite of the Kuiper belt object and possible dwarf planet 174567 Varda. It was discovered by Keith Noll et al. in 2009, at a separation of about 0.12 arcsec, using discovery images taken by the Hubble Space Telescope on 26 April 2009, and reported in 2011. At approximately 326 km in diameter (about 45% that of its primary), it is the fourth or fifth- largest known moon of a trans-Neptunian object, after Pluto I Charon, Eris I Dysnomia, Orcus I Vanth and very possibly Haumea I Hiʻiaka.
|
|
Aoede , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003. It received the temporary designation '.IAUC 8087: Satellites of Jupiter 2003 March 4 (Discovery)MPEC 2003-E11: S/2003 J 1, 2003 J 2, 2003 J 3, 2003 J 4, 2003 J 5, 2003 J 6, 2003 J 7 2003 March 4 (Discovery and ephemeris) Aoede is about 4 kilometres in diameter, and orbits Jupiter at an average distance of 23,044,000 km in 714.657 days, at an inclination of 160° to the ecliptic (162° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.4311.
|
|
Hegemone , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003, and given the temporary designation '.IAUC 8088: S/2003 J 8 2003 March 6 (discovery)MPEC 2003-E24: S/2003 J 8 2003 March 6 (discovery and ephemeris) Hegemone is about 3 kilometres in diameter, and orbits Jupiter at an average distance of 23,703,000 km in 745.500 days, at an inclination of 153° to the ecliptic (151° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.4077. It was named in March 2005 after Hegemone, one of the Graces, and a daughter of Zeus (Jupiter).
|
|
Kallichore , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard, et al. in 2003. It received the temporary designation '.IAUC 8089: Satellites of Jupiter 2003 March 7 (discovery)MPEC 2003-E29: S/2003 J 9, 2003 J 10, 2003 J 11, 2003 J 12; S/2003 J 1, 2003 J 6 2003 April 3 (discovery and ephemeris) Kallichore is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 23,112,000 km in 717.806 days, at an inclination of 165° to the ecliptic (164° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.2042.
|
|
'Jupiter LV, provisionally known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers led by Brett J. Gladman in 2003.MPEC 2003-G20: S/2003 J 18 April 4, 2003 (discovery) is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 20.220 Gm in 587.38 days, at an inclination of 146° to the ecliptic (148° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.1048.MPEC 2017-L09: S/2003 J 18 June 2, 2017 (recovery and ephemeris) It belongs to the Ananke group, retrograde irregular moons that orbit Jupiter between 22.8 and 24.1 Gm, at inclinations of roughly 150-155°.
|
|
Carpo , also ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003, and was provisionally designated as 'MPEC 2003-G67: S/2003 J 20 2003 April (discovery and ephemeris) until it received its name in early 2005. Carpo is about 3 kilometres (1.9 miles) in diameter, and orbits Jupiter at an average distance of 17.145 Gm (just over ten million miles) in 458.625 days, at an inclination of 56° to the ecliptic (55° to Jupiter's equator), and with a high eccentricity of 0.4316. It was named in March 2005 after Carpo, one of the Horae, and a daughter of Zeus (Jupiter).
|
|
Ganymede. Ganymede (Jupiter III), the third Galilean moon, is named after the mythological Ganymede, cupbearer of the Greek gods and Zeus's beloved. Ganymede is the largest natural satellite in the Solar System at 5262.4 kilometers in diameter, which makes it larger than the planet Mercury – although only at about half of its mass since Ganymede is an icy world. It is the only satellite in the Solar System known to possess a magnetosphere, likely created through convection within the liquid iron core. Ganymede is composed primarily of silicate rock and water ice, and a salt-water ocean is believed to exist nearly 200 km below Ganymede's surface, sandwiched between layers of ice.
|
|
Kepler-86, PH2 or KIC 12735740 (2MASS 19190326+5157453), is a G-type star distant within the constellation Cygnus. Roughly the size and temperature of the Sun, PH2 gained prominence when it was known to be the host of one of 42 planet candidates detected by the Planet Hunters citizen science project in its second data release. The candidate orbiting around PH2, known as PH2 b, had been determined to have a spurious detection probability of only 0.08%, thus effectively confirming its existence as a planet. Located in its parent star's habitable zone, PH2 b (or Kepler-86b) is a "Jupiter-size" gas giant which may have a natural satellite suitable for hosting life.
|
|
There are, however, key environmental differences which have a bearing on moons as potential sites for extraterrestrial life. The strongest candidates for natural satellite habitability are currently icy satellites such as those of Jupiter and Saturn—Europa and Enceladus respectively, although if life exists in either place, it would probably be confined to subsurface habitats. Historically, life on Earth was thought to be strictly a surface phenomenon, but recent studies have shown that up to half of Earth's biomass could live below the surface. Europa and Enceladus exist outside the circumstellar habitable zone which has historically defined the limits of life within the Solar System as the zone in which water can exist as liquid at the surface.
|
|
Galileo Galilei When Copernicus placed Earth among the planets, he also placed the Moon in orbit around Earth, making the Moon the first natural satellite to be identified. When Galileo discovered his four satellites of Jupiter in 1610, they lent weight to Copernicus's argument, because if other planets could have satellites, then Earth could too. However, there remained some confusion as to whether these objects were "planets"; Galileo referred to them as "four planets flying around the star of Jupiter at unequal intervals and periods with wonderful swiftness." Similarly, Christiaan Huygens, upon discovering Saturn's largest moon Titan in 1655, employed many terms to describe it, including "planeta" (planet), "stella" (star), "luna" (moon), and the more modern "satellite" (attendant).
|
|
This is a list of named craters on Callisto, one of the many moons of Jupiter, the most heavily cratered natural satellite in the Solar System (for other features, see list of geological features on Callisto). As of 2017, the Working Group for Planetary System Nomenclature has officially named a total of 141 craters on Callisto, more than on any other non-planetary object such as Ganymede (131), Rhea (128), Vesta (90), Ceres (90), Dione (73), Iapetus (58), Enceladus (53), Tethys (50) and Europa (41). Although some Callistoan craters refer to the nymph Callisto from Greek mythology, they are officially named after characters from myths and folktales of cultures of the Far North. .
|
|
Lyell Medal, Geological Society of London, 1876 This list of geology awards is an index to articles on notable awards for geology, an earth science concerned with the solid Earth, the rocks of which it is composed, and the processes by which they change over time. Geology can also include the study of the solid features of any terrestrial planet or natural satellite such as Mars or the Moon. The list is organized by region and country of the organization that sponsors the award, but awards are not always restricted to people from that country. See list of earth sciences awards for awards for earth sciences in general, and for other branches of earth science.
|
|
A geographical axis of rotation A (green), and showing the north geographical pole A1, and south geographical pole A2; also showing a magnetic field and the magnetic axis of rotation B (blue), and the north magnetic pole B1, and south magnetic pole B2. A geographical pole is either of the two points on a rotating body (planet, dwarf planet, natural satellite, sphere...etc.) where its axis of rotation intersects its surface. As with Earth's North and South Poles, they are usually called that body's "north pole" and "south pole", one lying 90 degrees in one direction from the body's equator and the other lying 90 degrees in the opposite direction from the equator. Every planet has geographical poles.
|
|
The Earth–Moon system is unique among planetary systems in that the ratio of the diameter of the Moon to the diameter of Earth is much greater than that of any other natural- satellite–planet ratio in the Solar System. At 3,474 km (2,158 miles) across, the Moon is 0.273 times the diameter of Earth. This is five times greater than the next largest moon-to-planet diameter ratio (with Neptune's largest moon at 0.055, Saturn's at 0.044, Jupiter's at 0.038 and Uranus' as 0.031). For the category of planetoids, among the five that are known in the Solar System, Charon has the largest ratio, being half (0.52) the diameter of Pluto.
|
|
'Autonoe , also known as ', is a natural satellite of Jupiter. Autonoe was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2001, and given the temporary designation '.IAUC 7900: Satellites of Jupiter 2002 May 16 (discovery)MPEC 2002-J54: Eleven New Satellites of Jupiter 2002 May 15 (discovery and ephemeris)MPEC 2002-V03: S/2001 J 1 2002 November 1 (revised ephemeris) Autonoe is about 4 kilometres in diameter, and orbits Jupiter at an average distance of 24,264,000 km in 772.168 days. It orbits at an inclination of 151° to the ecliptic (150° to Jupiter's equator) in a retrograde direction and with an eccentricity of 0.369.
|
|
In astronomy, a regular moon is a natural satellite following a relatively close and prograde orbit with little orbital inclination or eccentricity. They are believed to have formed in orbit about their primary, as opposed to irregular moons, which were captured. There are at least 57 regular satellites of the eight planets: one at Earth, eight at Jupiter, 23 named regular moons at Saturn (not counting hundreds or thousands of moonlets), 18 known at Uranus, and 7 small regular moons at Neptune (Neptune's largest moon Triton appears to have been captured). It is thought that Pluto's five moons and Haumea's two were formed in orbit about those dwarf planets out of debris created in giant collisions.
|
|
Tarqeq, also known as Saturn LII (provisional designation S/2007 S 1) is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on 13 April 2007 from observations taken between 5 January 2006 and 22 March 2007.MPEC 2007-G38: S/2007 S 1 13 April 2007 (discovery, prediscovery and ephemeris)IAUC 8836: S/2007 S 1, S/2007 S 2, and S/2007 S 3 11 May 2007 (discovery) It is named after Tarqeq, the Inuit moon god,IAUC 8873: Satellites of Saturn 20 September 2007 (naming) and is a member of the Inuit group of irregular satellites. It is about seven kilometres in diameter.
|
|
The meteors were particularly unusual in that there was no apparent radiant, that is to say, no point in the sky from which the meteors appeared to originate. The observations were analysed in detail, later the same year, by the astronomer Clarence Chant, leading him to conclude that as all accounts were positioned along a great circle arc, the source had been a small, short-lived natural satellite of the Earth. John A. O'Keefe, who conducted several studies of the event, proposed that the meteors should be referred to as the Cyrillids, in reference to the feast day of Cyril of Alexandria (February 9 in the Roman Catholic calendar from 1882–1969).
|
|
Cyllene , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003, receiving the temporary designation '.IAUC 8116: Satellites of Jupiter and Saturn 2003 April (discovery)MPEC 2003-G09: S/2003 J 13 2003 April (discovery and ephemeris) Cyllene is about 2 kilometres in diameter, and orbits Jupiter at an average distance of (23.4 million km) 23,396,000 km in 731.099 days (2.00 earth years), at an inclination of 140.149° to the ecliptic (139.543° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.4116. It was named in March 2005 after Cyllene, a naiad (stream nymph) or oread (mountain nymph) associated with Mount Cyllene, Greece.
|
|
The tectonic plates of the lithosphere on Earth Earth cutaway from center to surface, the lithosphere comprising the crust and lithospheric mantle (detail not to scale) A lithosphere ( [lithos] for "rocky", and [sphaira] for "sphere") is the rigid,Skinner, B.J. & Porter, S.C.: Physical Geology, page 17, chapt. The Earth: Inside and Out, 1987, John Wiley & Sons, outermost shell of a terrestrial-type planet, or natural satellite, that is defined by its rigid mechanical properties. On Earth, it is composed of the crust and the portion of the upper mantle that behaves elastically on time scales of thousands of years or greater. The outermost shell of a rocky planet, the crust, is defined on the basis of its chemistry and mineralogy.
|
|
Giovanni Cassini, in announcing his discovery of Saturn's moons Iapetus and Rhea in 1671 and 1672, described them as Nouvelles Planetes autour de Saturne ("New planets around Saturn"). However, when the "Journal de Scavans" reported Cassini's discovery of two new Saturnian moons in 1686, it referred to them strictly as "satellites", though sometimes Saturn as the "primary planet". When William Herschel announced his discovery of two objects in orbit around Uranus in 1787, he referred to them as "satellites" and "secondary planets". All subsequent reports of natural satellite discoveries used the term "satellite" exclusively,See primary citations in Timeline of discovery of Solar System planets and their moons though the 1868 book "Smith's Illustrated Astronomy" referred to satellites as "secondary planets".
|
|
A temporary satellite is an object which has been captured by the gravitational field of a planet and thus became the planet's natural satellite, but, unlike irregular moons of the larger outer planets of the Solar System, will eventually either leave its orbit around the planet or collide with the planet. The only observed examples are , a temporary satellite of Earth for nine months in 2006 and 2007, and , which was discovered in 2020. Some defunct space probes or rockets have also been observed on temporary satellite orbits. In astrophysics, a temporary satellite is any body that enters the Hill sphere of a planet at a sufficiently low velocity such that it becomes gravitationally bound to the planet for some period of time.
|
|
Skathi , or Saturn XXVII, is a natural satellite of Saturn. It was discovered by Brett Gladman, Kavelaars and colleagues in 2000, and given the temporary designation S/2000 S 8.IAUC 7538: S/2000 S 7, S/2000 S 8, S/2000 S 9 7 December 2000 (discovery) MPEC 2000-Y15: S/2000 S 1, S/2000 S 2, S/2000 S 7, S/2000 S 8, S/2000 S 9 19 December 2000 (discovery and ephemeris) Skathi is about 8 kilometres in diameter and orbits Saturn at an average distance of 15.576 Gm in 725.784 days, at an inclination of 149° to the ecliptic (150° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.246. Its rotation period is hours.
|
|
Eurydome , also known as ', is a natural satellite of Jupiter. It was discovered along with Hermippe by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2001, and given the temporary designation '.IAUC 7900: Satellites of Jupiter 2002 May (discovery)MPEC 2002-J54: Eleven New Satellites of Jupiter 2002 May (discovery and ephemeris) Eurydome is about 3 kilometres in diameter, and orbits Jupiter at an average distance of 23,231,000 km in 723.359 days, at an inclination of 149° to the ecliptic (147° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.3770. It was named in August 2003 after Eurydome in Greek mythology, who is sometimes described as the mother of the Graces by Zeus (Jupiter).
|
|
Sponde , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2001, and given the temporary designation '.IAUC 7900: Satellites of Jupiter 2002 May 16 (discovery)MPEC 2002-J54: Eleven New Satellites of Jupiter 2002 May 15 (discovery and ephemeris) Sponde is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 24,253,000 km in 771.604 days, at an inclination of 154° to the ecliptic (156° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.443. It was named in August 2003 after one of the Horae (Hours), which presided over the seventh hour (libations poured after lunch).
|
|
It has been implicated as a key agent in the warming of early Mars, with estimates of concentrations in the lower atmosphere as high as 100 ppm, though it only exists in trace amounts. On both Venus and Mars, as on Earth, its primary source is thought to be volcanic. The atmosphere of Io, a natural satellite of Jupiter, is 90% sulfur dioxide and trace amounts are thought to also exist in the atmosphere of Jupiter. As an ice, it is thought to exist in abundance on the Galilean moons—as subliming ice or frost on the trailing hemisphere of Io, and in the crust and mantle of Europa, Ganymede, and Callisto, possibly also in liquid form and readily reacting with water.
|
|
' is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003.IAUC 8087: Satellites of Jupiter 2003 March 4 (discovery)MPEC 2003-E11: S/2003 J 1, 2003 J 2, 2003 J 3, 2003 J 4, 2003 J 5, 2003 J 6, 2003 J 7 2003 March 4 (discovery and ephemeris) is about 2 km in diameter, and orbits Jupiter at an average distance of 23,571,000 km in 739.294 days, at an inclination of 147° to the ecliptic (149° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.3003. It belongs to the Pasiphae group, irregular retrograde moons orbiting Jupiter at distances ranging between 22.8 and 24.1 Gm, and with inclinations ranging between 144.5° and 158.3°.
|
|
' is a natural satellite of Jupiter, and is one of the smallest known natural satellites in the Solar System. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003.MPEC 2003-E29: S/2003 J 9, 2003 J 10, 2003 J 11, 2003 J 12; S/2003 J 1, 2003 J 6 April 3, 2003 (discovery and ephemeris) is about 1 kilometre (0.6 miles) in diameter, and orbits Jupiter at an average distance of 17,883 Mm in 489.72 days, at an inclination of 143° to the ecliptic (143° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.4920. It is the innermost of the outer irregular retrograde satellites of Jupiter, and might belong to the Ananke group.
|
|
Kore , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003 and given the provisional designation '.IAUC 8116: Satellites of Jupiter and Saturn 2003 April (discovery)MPEC 2003-G10: S/2003 J 14 2003 April (discovery and ephemeris) Kore is about 2 kilometers in diameter, and orbits Jupiter at an average distance of 23,239,000 km in 723.720 days, at an inclination of 141° to the ecliptic (139° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.2462. It belongs to the Pasiphae group, which is made up of irregular retrograde moons orbiting Jupiter at distances ranging between 22.8 and 24.1 Gm, and with inclinations ranging between 144.5° and 158.3°.
|
|
The similarity of its orbit with Earth was also very difficult to explain from natural sources, with ejecta from a recent Lunar impact or non-gravitational perturbations such as the Yarkovsky effect having been suggested. The first Earth Trojan asteroid, , was later identified and such objects could well be a source for objects like 1991 VG. 1991 VG has been a transient co-orbital of the horseshoe type in the past and it will return as such in the future; it was a natural satellite of Earth for about a month since 1992. This temporary capture may have taken place multiple times in the past and it is expected to repeat again in the future. It had an eccentricity of less than 1 with respect to the Earth from 23 February to 21 March 1992.
|
|
Hermippe , or ', is a natural satellite of Jupiter. It was discovered along with Eurydome by a team of astronomers from the Institute for Astronomy of the University of Hawaii led by David Jewitt and Scott S. Sheppard and Jan Kleyna in 2001, and given the temporary designation '.IAUC 7900: Satellites of Jupiter May 16, 2002 (discovery)MPEC 2002-J54: Eleven New Satellites of Jupiter May 15, 2002 (discovery and ephemeris) Hermippe is about 4 kilometres in diameter, and orbits Jupiter at an average distance of 21,500,000 kilometers in about 630 days, at an inclination of 151° to the ecliptic (149° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.2290. It was named in August 2003 by the IAU, after Hermippe, a lover of Zeus (Jupiter).
|
|
Polar ice cap on Mars, seen by the Hubble Telescope A polar ice cap or polar cap is a high-latitude region of a planet, dwarf planet, or natural satellite that is covered in ice.The National Snow and Ice Data Center Glossary There are no requirements with respect to size or composition for a body of ice to be termed a polar ice cap, nor any geological requirement for it to be over land, but only that it must be a body of solid phase matter in the polar region. This causes the term "polar ice cap" to be something of a misnomer, as the term ice cap itself is applied more narrowly to bodies that are over land, and cover less than 50,000 km2: larger bodies are referred to as ice sheets. The composition of the ice will vary.
|
|
Computer modelling of an impact in 2013 detected around the star NGC 2547-ID8 by the Spitzer Space Telescope and confirmed by ground observations suggests the involvement of large asteroids or protoplanets similar to the events believed to have led to the formation of terrestrial planets like the Earth.NASA's Spitzer Telescope Witnesses Asteroid Smashup Based on observations of the Solar System's large collection of natural satellites, they are believed common components of planetary systems; however, exomoons have so far eluded confirmation. The star 1SWASP J140747.93-394542.6, in the constellation Centaurus, is a strong candidate for a natural satellite. – "Mamajek thinks his team could be either observing the late stages of planet formation if the transiting object is a star or brown dwarf, or possibly moon formation if the transiting object is a giant planet" Indications suggest that the confirmed extrasolar planet WASP-12b also has at least one satellite.
|
|
One of the more common is that the humanoids in the story have evolved on an Earth-like planet or natural satellite, totally independently from Humans on Earth. However, some works have offered alternative explanations: In Star Trek, the explanation is given that a primordial humanoid civilization, the Ancient humanoids, seeded the Milky Way Galaxy with genetically-engineered cells to guide the evolution of life on a multitude of worlds toward a humanoid form. In the television series Stargate SG-1, the Jaffa are explained as being an hundred-thousand year offshoot of humanity bred by the Goa'uld to suit their purposes, hence their almost-human appearance and physiology, while many other "alien" characters are actually the descendants of human-slaves who were removed from Earth by the Goa'uld. Any humans isolated on multiple planets after 100k+ years of adaptations would most certainly seem "alien" to Earthlings.
|
|
An 1875 geological map of Europe, compiled by the Belgian geologist André Dumont (colors indicate the distribution of rocks of different ages and types across the continent, as they were known then) Geology (from the Ancient Greek γῆ, gē ("earth") and -λoγία, -logia, ("study of", "discourse")) is an Earth science concerned with the solid Earth, the rocks of which it is composed, and the processes by which they change over time. Geology can also include the study of the solid features of any terrestrial planet or natural satellite such as Mars or the Moon. Modern geology significantly overlaps all other Earth sciences, including hydrology and the atmospheric sciences, and so is treated as one major aspect of integrated Earth system science and planetary science. Aerial view of ; Hot Springs, Midway & Lower Geyser Basin, Kinney Lake and Mount Whitehorn near Mount Robson, Canada Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure.
|
|
Although it is too distant to be considered a true natural satellite of Earth, it is the best and most stable example to date of a near-Earth companion, or quasi-satellite. "Since loops around our planet, but never ventures very far away as we both go around the Sun, we refer to it as a quasi-satellite of Earth", said Paul Chodas, manager of NASA's Center for Near-Earth Object (NEO) Studies at the Jet Propulsion Laboratory in Pasadena, California. In its yearly trek around the Sun, Kamoʻoalewa spends about half of the time closer to the Sun than Earth is (that is, the asteroid is inside the Earth's orbit) and passes ahead of our planet, and about half of the time farther away (crosses outside Earth's orbit), causing it to fall behind. Its orbit is also tilted a little, causing it to bob up and then down once each year through Earth's orbital plane.
|
|
Megaclite , also known as ', is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2000, and given the temporary designation '.IAUC 7555: Satellites of Jupiter 2001 January 5 (discovery)MPEC 2001-A29: S/2000 J 7, S/2000 J 8, S/2000 J 9, S/2000 J 10, S/2000 J 11 2001 January 15 (discovery and ephemeris)MPEC 2001-T59: S/2000 J 8, S/2000 J 9, S/2000 J 10 2001 October 15 (revised ephemeris) Megaclite is about 6 kilometres in diameter, and orbits Jupiter at an average distance of 24,687,000 kilometers in 792.437 days, at an inclination of 150° to the ecliptic (148° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.308. It was named in October 2002 after Megaclite, mother by Zeus (Jupiter) of Thebe and Locrus in Greek mythology.
|
|
The Rare Earth hypothesis argues that the evolution of biological complexity requires a host of fortuitous circumstances, such as a galactic habitable zone, a central star and planetary system having the requisite character, the circumstellar habitable zone, a right-sized terrestrial planet, the advantage of a gas giant guardian like Jupiter and a large natural satellite, conditions needed to ensure the planet has a magnetosphere and plate tectonics, the chemistry of the lithosphere, atmosphere, and oceans, the role of "evolutionary pumps" such as massive glaciation and rare bolide impacts, and whatever led to the appearance of the eukaryote cell, sexual reproduction and the Cambrian explosion of animal, plant, and fungi phyla. The evolution of human intelligence may have required yet further events, which are extremely unlikely to have happened were it not for the Cretaceous–Paleogene extinction event 66 million years ago removing dinosaurs as the dominant terrestrial vertebrates. In order for a small rocky planet to support complex life, Ward and Brownlee argue, the values of several variables must fall within narrow ranges. The universe is so vast that it could contain many Earth-like planets.
|
|