"around Mars, the shadow of Phobos was seen in pictures transmitted to Earth. One of these photos was from the NASA rover ""Opportunity"". Solar eclipses on Mars The two moons of Mars, Phobos and Deimos, are much smaller than the Moon, greatly reducing the frequency of solar eclipses on that planet. Neither moon's apparent diameter is large enough to cover the disk of the sun, and therefore they are annular solar eclipses and can also be considered transits. Due to the small size of Phobos (about ) and its rapid orbital motion, an observer on the surface of Mars would"
"Phobos and Deimos in fiction Mars has two moons, Phobos and Deimos. Due to their small size, both moons were discovered only in 1877, by astronomer Asaph Hall. Nevertheless, they frequently feature in works of science fiction. Some of the earliest mentions of Mars's moons in fiction predate their discovery. In Jonathan Swift's famous satire ""Gulliver's Travels"" (1726), the astronomers of flying island Laputa are described as having discovered two satellites of Mars. Voltaire's short story ""Micromégas"" (1752), about alien visitors from Sirius and Saturn, also describes Mars as having two moons. Voltaire is thought to have been influenced by"
"or satellites, which revolve about Mars"". This may have influenced Voltaire, whose 1750 story ""Micromégas"" also refers to two moons of Mars. In 1877, Asaph Hall discovered the two real moons of Mars, Deimos and Phobos; in 1973 craters on Deimos were named Swift and Voltaire, and from 2006 numerous features on Phobos were named after elements from ""Gulliver's Travels"", including Laputa Regio, Lagado Planitia, and several craters. The term ""Lilliputian"" has entered many languages as an adjective meaning ""small and delicate"". There is even a brand of small cigar called Lilliput. There is a series of collectable model houses"
"crater on the Moon as well as Hall crater on the Martian moon Phobos are named in his honor. Asaph Hall Asaph Hall III (October 15, 1829 – November 22, 1907) was an American astronomer who is most famous for having discovered the moons of Mars, Deimos and Phobos, in 1877. He determined the orbits of satellites of other planets and of double stars, the rotation of Saturn, and the mass of Mars. Hall was born in Goshen, Connecticut, the son of Asaph Hall II (1800–42), a clockmaker, and Hannah Palmer (1804–80). His paternal grandfather Asaph Hall I (June 11,"
"Swift. In recognition of these mentions, many geological features of Phobos and Deimos are named after characters and places from ""Gulliver's Travels"", including among others ""Laputa Regio"" and ""Lagado Planitia"" on Phobos, and craters Swift and Voltaire on Deimos. Phobos and Deimos in fiction Mars has two moons, Phobos and Deimos. Due to their small size, both moons were discovered only in 1877, by astronomer Asaph Hall. Nevertheless, they frequently feature in works of science fiction. Some of the earliest mentions of Mars's moons in fiction predate their discovery. In Jonathan Swift's famous satire ""Gulliver's Travels"" (1726), the astronomers of"
"Deimos (moon) Deimos (systematic designation: Mars II) is the smaller and outermost of the two natural satellites of the planet Mars, the other being Phobos. Deimos has a mean radius of and takes 30.3 hours to orbit Mars. Deimos is from Mars, much further than Mars's other moon, Phobos. It is named for Deimos who in Greek mythology is the twin brother of Phobos, and personifies terror. Deimos was discovered by Asaph Hall, III at the United States Naval Observatory in Washington, D.C. on 12 August 1877, at about 07:48 UTC (given in contemporary sources as ""11 August 14:40"" Washington"
"Phobos (moon) Phobos ( , , ; systematic designation: ) is the innermost and larger of the two natural satellites of Mars, the other being Deimos. Both moons were discovered in 1877 by American astronomer Asaph Hall. Phobos is a small, irregularly shaped object with a mean radius of and is seven times as massive as the outer moon, Deimos. Phobos is named after the Greek god Phobos, a son of Ares (Mars) and Aphrodite (Venus) and the personification of horror (cf. phobia). Phobos orbits from the Martian surface, closer to its primary body than any other known planetary moon."
"notable on Mars which has two natural satellites, Phobos and Deimos. Both moons orbit Mars in an eastward (prograde) direction, however Deimos has an orbital period of 1.23 Martian sidereal days, making it supersynchronous, whereas Phobos has an orbital period of 0.31 Martian sidereal days making it subsynchronous. Consequently, although both moons are travelling in an eastward (prograde) direction, they appear to be travelling in opposite directions when viewed from the surface of Mars due to their orbital periods in relation to the rotational period of the planet. All other planetary bodies in the Solar System also appear to periodically"
"place occur more or less symmetrically before and after the winter solstice (however, the large eccentricity of Mars's orbit prevents true symmetry). Observers on Mars can also view lunar eclipses of Phobos and Deimos. Phobos spends about an hour in Mars's shadow; for Deimos it is about two hours. Surprisingly, despite its orbit being nearly in the plane of Mars's equator and despite its very close distance to Mars, there are some occasions when Phobos escapes being eclipsed. Phobos and Deimos both have synchronous rotation, which means that they have a ""far side"" that observers on the surface of Mars"
"Mars appears to be the angular diameter as seen from Earth (0.35°), and sends 40% of the light, approximately the brightness of a slightly cloudy afternoon on Earth. On June 3, 2014, the ""Curiosity"" rover on Mars observed the planet Mercury transiting the Sun, marking the first time a planetary transit has been observed from a celestial body besides Earth. Mars has two small moons: Phobos and Deimos. From the Martian surface, Phobos has one-third to one-half the angular diameter of the Sun while Deimos is barely more than a dot (only 2′ angular diameter). The orbital period of Phobos"
"could be released in front of the spacecraft during the descent maneuver and then resulting in a densification of the atmosphere just in front of the spacecraft. Deimos (moon) Deimos (systematic designation: Mars II) is the smaller and outermost of the two natural satellites of the planet Mars, the other being Phobos. Deimos has a mean radius of and takes 30.3 hours to orbit Mars. Deimos is from Mars, much further than Mars's other moon, Phobos. It is named for Deimos who in Greek mythology is the twin brother of Phobos, and personifies terror. Deimos was discovered by Asaph Hall,"
"from the surface of Phobos -from a permanent outpost, to a transfer orbit. This sand could be released in front of the spacecraft during the descent maneuver and then resulting in a densification of the atmosphere just in front of the spacecraft. Phobos (moon) Phobos ( , , ; systematic designation: ) is the innermost and larger of the two natural satellites of Mars, the other being Deimos. Both moons were discovered in 1877 by American astronomer Asaph Hall. Phobos is a small, irregularly shaped object with a mean radius of and is seven times as massive as the outer"
"writers and others who have contributed to the study of Mars. Craters smaller than 60 km are named for towns and villages of the world with populations of less than 100,000. Large valleys are named for the word ""Mars"" or ""star"" in various languages; small valleys are named for rivers. Large albedo features retain many of the older names, but are often updated to reflect new knowledge of the nature of the features. For example, ""Nix Olympica"" (the snows of Olympus) has become ""Olympus Mons"" (Mount Olympus). The surface of Mars as seen from Earth is divided into two kinds"
"give these moons their names; they were named by his son John in 1847 and 1852, respectively, after his death. Herschel measured the axial tilt of Mars and discovered that the martian ice caps, first observed by Giovanni Domenico Cassini (1666) and Christiaan Huygens (1672), changed size with that planet's seasons. It has been suggested that Herschel might have discovered rings around Uranus. Herschel introduced but did not create the word ""asteroid"", meaning ""star-like"" (from the Greek ""asteroeides"", ""aster"" ""star"" + ""-eidos"" ""form, shape""), in 1802 (shortly after Olbers discovered the second minor planet, 2 Pallas, in late March), to"
"the smaller and outer of Mars' two moons. It was discovered by Asaph Hall in 1877. 1877 Phobos Phobos is the larger and closer of Mars' two small moons. It was discovered by Asaph Hall in 1877. 1888 Cliff Palace The Cliff Palace is the largest cliff dwelling in North America. The structure built by the Ancient Pueblo Peoples is located in Mesa Verde National Park in their former homeland region. The cliff dwelling and park are in the southwestern corner of Colorado, in the Southwestern United States. The ancient ruins of Cliff Palace were co-discovered during a snowstorm in"
"Center (DLR) and a study team with representatives of the scientific community and the space industry. The mission would explore the origin and the evolution of the two Martian moons, and would also contribute to the general questions of planetary formation and the workings of the Solar System. The origin of the Martian moons is controversial. Phobos and Deimos both have much in common with carbonaceous C-type asteroids, with spectra, albedo, and density very similar to those of C- or D-type asteroids. Based on their similarity, one hypothesis is that both moons may be captured main-belt asteroids. Another hypothesis is"
"Ares (the Greek equivalent of the Roman god Mars). The Galilean moons of Jupiter (Io, Europa, Ganymede and Callisto) were named by Simon Marius soon after their discovery in 1610. However, by the late 19th century these names had fallen out of favor, and for a long time it was most common to refer to them in the astronomical literature simply as ""Jupiter I"", ""Jupiter II"", etc., or as ""the first satellite of Jupiter"", ""Jupiter's second satellite"", etc. By the first decade of the 20th century, the names Io, Europa, Ganymede, and Callisto had once again recovered popularity, but the"
"landed on Mars, individual small features such as rocks, dunes, and hollows have often been given informal names. Many of these are frivolous: features have been named after ice cream (such as Cookies N Cream); cartoon characters (such as SpongeBob SquarePants and Patrick); and '70s music acts (such as ABBA and the Bee Gees). Features on Deimos are named after authors who wrote about Martian satellites. There are currently two named features on Deimos - Swift crater and Voltaire crater - after Jonathan Swift and Voltaire who predicted the presence of Martian moons. All features on Phobos are named after"
"named after this mythological figure. The god’s Roman equivalent was Formido or Metus. Deimos was the son of Ares and Aphrodite. He is the twin brother of Phobos and nephew of the goddess Enyo who accompanied her brother Ares into battle, as well as his father's attendants, Trembling, Fear, Dread and Panic. Deimos is more of a personification and an abstraction of the sheer terror that is brought by war and he never appeared as an actual character in any story in Greek Mythology. His Roman equivalent was Formido or Metus. Asaph Hall, who discovered the moons of Mars, named"
"Asaph Hall Asaph Hall III (October 15, 1829 – November 22, 1907) was an American astronomer who is most famous for having discovered the moons of Mars, Deimos and Phobos, in 1877. He determined the orbits of satellites of other planets and of double stars, the rotation of Saturn, and the mass of Mars. Hall was born in Goshen, Connecticut, the son of Asaph Hall II (1800–42), a clockmaker, and Hannah Palmer (1804–80). His paternal grandfather Asaph Hall I (June 11, 1735 – Mar. 29, 1800) was a Revolutionary War officer and Connecticut state legislator. His father died when he"
"break up when it reaches approximately 2.1 Mars radii. When Phobos is eventually torn apart by tidal forces, a fraction of the debris will likely form a planetary ring around Mars, which may last from one million to one hundred million years. The origin of the Martian moons is still controversial. Phobos and Deimos both have much in common with carbonaceous C-type asteroids, with spectra, albedo, and density very similar to those of C- or D-type asteroids. Based on their similarity, one hypothesis is that both moons may be captured main-belt asteroids. Both moons have very circular orbits which lie"
"Moon, Johann Heinrich Mädler and Wilhelm Beer were the first ""areographers"". They began by establishing that most of Mars's surface features were permanent and by more precisely determining the planet's rotation period. In 1840, Mädler combined ten years of observations and drew the first map of Mars. Rather than giving names to the various markings, Beer and Mädler simply designated them with letters; Meridian Bay (Sinus Meridiani) was thus feature """"a"""". Today, features on Mars are named from a variety of sources. Albedo features are named for classical mythology. Craters larger than 60 km are named for deceased scientists and"
"1877 by Asaph Hall; they are named after the characters Phobos (panic/fear) and Deimos (terror/dread), who, in Greek mythology, accompanied their father Ares, god of war, into battle. Mars was the Roman counterpart of Ares. In modern Greek, the planet retains its ancient name ""Ares"" (Aris: ""Άρης""). From the surface of Mars, the motions of Phobos and Deimos appear different from that of the Moon. Phobos rises in the west, sets in the east, and rises again in just 11 hours. Deimos, being only just outside synchronous orbit – where the orbital period would match the planet's period of rotation"
"Mountains, the Caucasus, and the Alps. Mars, like Earth, has ice caps at its poles. In addition to frozen water, Mars ice caps also have frozen carbon dioxide, commonly known as dry ice. In addition, Mars has seasons similar to Earth. The North Pole of Mars has a permanent water ice cap and a winter-only dry ice cap. On the south pole, both the water and carbon dioxide are permanently frozen. Europa, a moon of Jupiter, is covered with a permanent sheet of water ice, similar to Antarctica. Scientists theorize that it may have sub-glacial lakes similar to those seen"
"Moons of Pluto The dwarf planet Pluto has five moons down to a detection limit of about 1 km in diameter. In order of distance from Pluto, they are Charon, Styx, Nix, Kerberos, and Hydra. Charon, the largest of the five moons, is mutually tidally locked with Pluto, and is massive enough that Pluto–Charon is sometimes considered a double dwarf planet. The innermost and largest moon, Charon, was discovered by James Christy on 22 June 1978, nearly half a century after Pluto was discovered. This led to a substantial revision in estimates of Pluto's size, which had previously assumed that"
"moons, discovered in 1787, did not receive names until 1852, a year after two more moons had been discovered. The responsibility for naming was taken by John Herschel, son of the discoverer of Uranus. Herschel, instead of assigning names from Greek mythology, named the moons after magical spirits in English literature: the fairies Oberon and Titania from William Shakespeare's ""A Midsummer Night's Dream"", and the sylphs Ariel and Umbriel from Alexander Pope's ""The Rape of the Lock"" (Ariel is also a sprite in Shakespeare's ""The Tempest""). The reasoning was presumably that Uranus, as god of the sky and air, would"
"to six moons and maybe even a ring. For nearly fifty years, Herschel's instrument was the only one the moons had been seen with. In the 1840s, better instruments and a more favourable position of Uranus in the sky led to sporadic indications of satellites additional to Titania and Oberon. Publications hesitated between William Herschel's designations (where Titania and Oberon are Uranus II and IV) and William Lassell's (where they are sometimes I and II). With the confirmation of Ariel and Umbriel, Lassell numbered the moons I through IV from Uranus outward, and this finally stuck. The first two Uranian"
"Moons of Neptune Neptune has 14 known moons, which are named for minor water deities in Greek mythology. By far the largest of them is Triton, discovered by William Lassell on October 10, 1846, 17 days after the discovery of Neptune itself; over a century passed before the discovery of the second natural satellite, Nereid. Neptune's outermost moon Neso, which has an orbital period of about 26 Julian years, orbits further from its planet than any other moon in the Solar System. Triton is unique among moons of planetary mass in that its orbit is retrograde to Neptune's rotation and"
"– rises as expected in the east but slowly. Despite the 30-hour orbit of Deimos, 2.7 days elapse between its rise and set for an equatorial observer, as it slowly falls behind the rotation of Mars. Because the orbit of Phobos is below synchronous altitude, the tidal forces from the planet Mars are gradually lowering its orbit. In about 50 million years, it could either crash into Mars's surface or break up into a ring structure around the planet. The origin of the two moons is not well understood. Their low albedo and carbonaceous chondrite composition have been regarded as"
"Moons of Saturn The moons of Saturn are numerous and diverse, ranging from tiny moonlets less than 1 kilometer across to the enormous Titan, which is larger than the planet Mercury. Saturn has 62 moons with confirmed orbits, 53 of which have names and only 13 of which have diameters larger than 50 kilometers, as well as dense rings with complex orbital motions of their own. Seven Saturnian moons are large enough to be ellipsoidal in shape, yet only two of those, Titan and Rhea, are currently in hydrostatic equilibrium. Particularly notable among Saturn's moons are Titan, the second-largest moon"
"Janus is named after the two-faced Roman god Janus. Although the name was informally proposed soon after the initial 1966 discovery, it was not officially adopted until 1983, when Epimetheus was also named. The ""Oxford English Dictionary"" lists the adjectival form of the moon's name as ""Janian"". Janus's orbit is co-orbital with that of Epimetheus. Janus's mean orbital radius from Saturn is, as of 2006 (as shown by green color in the adjacent picture), only 50 km less than that of Epimetheus, a distance smaller than either moon's mean radius. In accordance with Kepler's laws of planetary motion, the closer"
"was probably deposited as snow during a different climate in the past. The tilt of Mars changes far more than the Earth's tilt. At times the tilt changes such that the polar ice caps sublimate and the atmosphere carries the moisture to the mid-latitudes where snow falls and accumulates. The Earth's tilt is stabilized by our rather large moon. The two moons of Mars are tiny. It would be difficult to take a hike on the fretted terrain because the surface is folded, pitted, and often covered with linear striations. The striations show the direction of movement. Much of this"
"a few million years ago, the tilt of the axis of Mars was 45 degrees instead of its present 25 degrees. Its tilt, also called obliquity, varies greatly because its two tiny moons cannot stabilize it, like our relatively large moon does to the Earth. During such periods of high tilt, the summer rays of the sun strike the mid-latitude crater surfaces straight on, thus the surface remains dry. Note that at high tilt, the ice caps at the poles disappear, the atmosphere thickness, and the moisture in the atmosphere goes up. These conditions cause snow and frost to appear"