Phobos

Enhanced-color view of Phobos obtained by Mars Reconnaissance Orbiter on March 23, 2008. NASA 's Mars Reconnaissance Orbiter ( MRO) is a multipurpose Spacecraft designed to conduct Reconnaissance and exploration of Mars Events 1174 - Jocelin, Abbot of Melrose, is elected Bishop of Glasgow. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
Discovery
Discovered by	Asaph Hall
Discovery date	August 18, 1877
Orbital characteristics
Epoch J2000
Periapsis	9,235. Asaph Hall ( October 15, 1829 &ndash November 22, 1907) was an American astronomer who is most famous for having discovered Events 293 BC - The oldest known Roman temple to Venus is founded starting the institution of Vinalia Rustica. Year 1877 ( MDCCCLXXVII) was a Common year starting on Monday (link will display the full calendar of the Gregorian calendar (or a Common In Physics, an orbit is the gravitationally curved path of one object around a point or another body for example the gravitational orbit of a planet around a star In Astronomy, an epoch is a moment in time used as a reference for the Orbital elements of a Celestial body. In Astronomy, an epoch is a moment in time used as a reference for the Orbital elements of a Celestial body. In Celestial mechanics, an apsis, plural apsides (ˈæpsɨdɪːz is the point of greatest or least distance of the Elliptical orbit of an object from 6 km
Apoapsis	9,518. In Celestial mechanics, an apsis, plural apsides (ˈæpsɨdɪːz is the point of greatest or least distance of the Elliptical orbit of an object from 8 km
Semi-major axis	9,377. In Geometry, the semi-major axis (also semimajor axis) is used to describe the dimensions of ellipses and hyperbolae 2 km[1]
Eccentricity	0. The kilometre ( American spelling: kilometer) symbol km is a unit of Length in the Metric system, equal to one thousand In Astrodynamics, under standard assumptions, any Orbit must be of Conic section shape 0151
Orbital period	0. The orbital period is the time taken for a given object to make one complete Orbit about another object 318 910 23 d (7 h 39. A day (symbol d is a unit of Time equivalent to 24 Hours and the duration of a single Rotation of planet Earth with respect to the The hour (symbol h) is a unit of Time. It is not an SI unit but is accepted for use with the SI 2 min)
Average orbital speed	2. A minute is a Unit of measurement of Time or of Angle. The minute is a unit of Time equal to 1/60th of an Hour or 60 The orbital speed of a body generally a Planet, a Natural satellite, an artificial satellite, or a Multiple star, is the speed at which it 138 km/s
Inclination	1. The second ( SI symbol s) sometimes abbreviated sec, is the name of a unit of Time, and is the International System of Units Inclination in general is the Angle between a Reference plane and another plane or axis of direction 093° (to Mars' equator) 0. This article describes the unit of angle For other meanings see Degree. 046° (to local Laplace plane) 26. The Laplace plane, named after Pierre-Simon Laplace, is defined as the mean plane occupied by the orbit of a Satellite during a Precession cycle 04° (to the ecliptic)
Satellite of	Mars
Physical characteristics
Dimensions	26. The ecliptic is the apparent path that the Sun traces out in the sky during the year A natural satellite or moon is a Celestial body that Orbits a Planet or smaller body which is called the primary. 8 × 21 × 18. 4 km
Mean radius	11. 1 km[2] (0. 0021 Earths)
Surface area	~6,100 km² (11. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 Equation A spheroid centered at the origin and rotated about the z axis is defined by the implicit equation \left(\frac{x}{a}\right^2+\left(\frac{y}{a}\right^2+\left(\frac{z}{b}\right^2 Square Kilometre ( US spelling square kilometer) symbol km2, is a decimal multiple of the SI unit of 9 µEarths)
Volume	~5,700 km³ (5. The volume of any solid plasma vacuum or theoretical object is how much three- Dimensional space it occupies often quantified numerically CM3 redirects here If you were looking for the 3rd game in the Cooking Mama series abbreviated as CM3 see here. 0 nEarths)
Mass	1. Mass is a fundamental concept in Physics, roughly corresponding to the Intuitive idea of how much Matter there is in an object 07×1016 kg[3] (1. 8 nEarths)
Mean density	1. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different 872 g/cm³[2]
Equatorial surface gravity	0. For other uses of the words gram or gramme see Gram (disambiguation. A cubic centimetre or cubic centimeter (symbol cm3 —the abbreviation cc, though widely used is deprecated is a commonly used unit of Volume The surface gravity, g, of an astronomical or other object is the Gravitational acceleration experienced at its surface 0084-0. 0019 m/s² (8. 4-1. 9 mm/s²) (860-190 µg)
Escape velocity	11. The Millimetre ( American spelling: millimeter, symbol mm) is a unit of Length in the Metric system, equal to g-force (also G-force, g-load) is a measurement of an object's Acceleration expressed in g s In Physics, escape velocity is the speed where the Kinetic energy of an object is equal to the magnitude of its Gravitational potential energy 3 m/s (40 km/hr)[3]
Rotation period	synchronous
Equatorial rotation velocity	11. (For the South African airport with IATA code "KMH" see Johan Pienaar Airport. The rotation period of an astronomical object is the time it takes to complete one revolution around its Axis of rotation relative to the background stars In Astronomy, synchronous rotation is a planetological term describing a body orbiting another where the orbiting body takes as long to rotate 0 km/h (at longest axis' tips)
Axial tilt	0°
Albedo	0. In Astronomy, axial tilt is the Inclination angle of a planet's rotational axis in relation to its orbital plane. The albedo of an object is the extent to which it diffusely reflects light from the sun 071[2]
Temperature	~233 K
Apparent magnitude	11. Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic The apparent magnitude ( m) of a celestial body is a measure of its Brightness as seen by an observer on Earth, normalized to the value 3[4]

Phobos (pronounced /ˈfoʊbəs/ foe'-bəs, or as Greek Φόβος) (systematic designation: Mars I) is the larger and closer of Mars' two moons (the other being Deimos). In ancient times only the Sun and Moon, a few hundred Stars and the most easily visible Planets had names A natural satellite or moon is a Celestial body that Orbits a Planet or smaller body which is called the primary. TemplateInfobox Planet.--> Deimos (ˈdaɪməs; also /ˈdiːməs/ It is named after the Greek god Phobos (which means "fear"), a son of Ares (Mars). Greek mythology is the body of stories belonging to the ancient Greeks concerning their gods and Heroes the nature of the world and the origins and significance Phobos ( Ancient Greek, "Fear" is the embodiment of Fear and horror in Greek mythology. In Greek mythology, Ares ( Ancient Greek:, Μodern Greek Άρης) is the son of Zeus and Hera. A small, irregularly shaped object, Phobos orbits about 9,377 km (5,823 mi) above the center of Mars, closer to its primary than any other planetary moon. The kilometre ( American spelling: kilometer) symbol km is a unit of Length in the Metric system, equal to one thousand A mile is a unit of Length, usually used to measure Distance, in a number of different systems including Imperial units United States

Discovery

Asaph Hall, discoverer of Phobos. Asaph Hall ( October 15, 1829 &ndash November 22, 1907) was an American astronomer who is most famous for having discovered

Main article: Discovery of the Martian moons

Phobos was discovered by American astronomer Asaph Hall, Sr., on August 18, 1877, at the US Naval Observatory in Washington, D.C., at about 09:14 GMT (contemporary sources, using the pre-1925 astronomical convention that began the day at noon, give the time of discovery as August 17 16:06 Washington mean time). The discovery of the two moons of Mars, Phobos and Deimos, occurred in 1877 when American astronomer Asaph Hall Sr Asaph Hall ( October 15, 1829 &ndash November 22, 1907) was an American astronomer who is most famous for having discovered Events 293 BC - The oldest known Roman temple to Venus is founded starting the institution of Vinalia Rustica. Year 1877 ( MDCCCLXXVII) was a Common year starting on Monday (link will display the full calendar of the Gregorian calendar (or a Common The United States Naval Observatory ( USNO) is one of the oldest Scientific agencies in the United States. Washington DC ( formally the District of Columbia and commonly referred to as Washington, the District, or simply D Greenwich Mean Time ( GMT) is a term originally referring to mean solar time at the Royal Observatory in Greenwich, London Events 986 - A Byzantine army was destroyed in the pass of Trajan's Gate by the Bulgarians under the Comitopuli Washington mean time was the time at the meridian through the center of the old dome atop the main building at the old US Naval Observatory at Washington D ^[5][6][7] Hall also discovered Deimos, Mars' other moon. TemplateInfobox Planet.--> Deimos (ˈdaɪməs; also /ˈdiːməs/

The names, originally spelled Phobus and Deimus respectively, were suggested by Henry Madan (1838–1901), Science Master of Eton, from Book XV of the Iliad, where Ares summons Dread (Deimos) and Fear (Phobos). Eton College, or just Eton, is a world-famous British Independent school for boys founded in 1440 by King Henry VI. The Iliad ( Greek: Ἰλιάς (Ancient Ιλιάδα (Modern is together with the Odyssey, one of two ancient In Greek mythology, Ares ( Ancient Greek:, Μodern Greek Άρης) is the son of Zeus and Hera. In Greek mythology, Deimos ( Δεῖμος &ndash " dread " was the Personification of dread. Phobos ( Ancient Greek, "Fear" is the embodiment of Fear and horror in Greek mythology. ^[8][9]

Physical characteristics

A mosaic of three separate images taken by Viking 1 on October 19, 1978. Viking 1 was the first of two spacecraft sent to Mars as part of NASA 's Viking program, and holds the record for the longest Mars surface mission Events 202 BCE - The Battle of Zama results in the defeat of Carthage and Hannibal. Year 1978 ( MCMLXXVIII) was a Common year starting on Sunday (link displays the 1978 Gregorian calendar) The large crater (mostly in darkness) on the upper left is Stickney. Stickney crater is the largest crater on Phobos, which is a satellite of Mars.

Phobos is one of the least-reflective bodies in the solar system. Spectroscopically it appears to be similar to the D-type asteroids,^[10] and is apparently of composition similar to carbonaceous chondrite material. Asteroids, sometimes called Minor planets or planetoids', are bodies—primarily of the inner Solar System —that are smaller than planets but A carbonaceous chondrite or a C-type chondrite is a type of chondritic Meteorite which contains high levels of Water and Organic compounds ^[11] Phobos' density is too low to be solid rock, however, and it is known to have significant porosity. Porosity is a measure of the void spaces in a material and is measured as a fraction between 0–1 or as a Percentage between 0–100% ^[12][13][14] These results led to the suggestion that Phobos might contain a substantial reservoir of ice. Spectral observations indicate that the surface regolith layer lacks hydration,^[15][16] but ice below the regolith is not ruled out. ^[17]

Faint dust rings produced by Phobos and Deimos have long been predicted but attempts to observe these rings have, to date, failed. ^[18] Recent images from Mars Global Surveyor indicate that Phobos is covered with a layer of fine-grained regolith at least 100 metres thick; it is believed to have been created by impacts from other bodies, but it is not known how the material stuck to an object with almost no gravity. The Mars Global Surveyor ( MGS) was a US Spacecraft developed by NASA and the Jet Propulsion Laboratory and launched Regolith ( Greek: "blanket rock" is a layer of loose Heterogeneous material covering solid rock. ^[19]

Phobos is highly nonspherical, with dimensions of 27 × 21. 6 × 18. 8 km. Because of its shape alone, the gravity on its surface varies by about 210%; the tidal forces raised by Mars more than double this variation (to about 450%) because they compensate for a little more than half of Phobos' gravity at its sub- and anti-Mars poles.

Phobos is heavily cratered. In the broadest sense the term impact crater can be applied to any depression natural or manmade resulting from the high velocity impact of a projectile with larger body ^[20] The most prominent surface feature is Stickney crater, named after Asaph Hall's wife, Angeline Stickney Hall, Stickney being her maiden name. Stickney crater is the largest crater on Phobos, which is a satellite of Mars. Chloe Angeline Stickney Hall ( November 1 1830 &ndash July 3[[ 892]] was the wife of Astronomer Asaph Hall. Like Mimas's crater Herschel on a smaller scale, the impact that created Stickney must have almost shattered Phobos. TemplateInfobox Planet. --> Mimas (ˈmaɪməs, or as Greek Herschel (ˈhɝːʃəl is a huge crater on the Saturnian moon Mimas. ^[21] Many grooves and streaks also cover the oddly shaped surface. The grooves are typically less than 30 m deep, 100 to 200 m wide, and up to 20 km in length, and were originally assumed to have been the result of the same impact that created Stickney. Analysis of results from the Mars Express spacecraft, however, revealed that the grooves are not in fact radial to Stickney, but are centered on the leading apex of Phobos in its orbit (which is not far from Stickney), and must have been excavated by material ejected into space by impacts on the surface of Mars. Mars Express is a Space exploration mission being conducted by the European Space Agency (ESA ^[22] The grooves thus formed as crater chains, and all of them fade away as the trailing apex of Phobos is approached. A crater chain is a line of craters along the surface of an astronomical body They have been grouped into 12 or more families of varying age, presumably representing at least 12 Martian impact events. ^[22]

The unique Kaidun meteorite is claimed to be a piece of Phobos, but this has been difficult to verify since little is known about the detailed composition of the moon. The Kaidun meteorite is a Meteorite that fell on March 12, 1980 on a Soviet Military base (lat ^[23]

Orbital characteristics

Orbits of Phobos and Deimos (to scale), seen from above Mars' north pole

Phobos's unusually close orbit around its parent planet produces some unusual effects.

As seen from Phobos, Mars would appear 6,400 times larger and 2,500 times brighter than the full Moon appears from Earth, taking up a quarter of the width of a celestial hemisphere.

Phobos orbits Mars below the synchronous orbit radius, meaning that it moves around Mars faster than Mars itself rotates. A synchronous orbit is an Orbit in which an orbiting body (usually a Satellite) has a period equal to the average rotational period of the body being orbited (usually Therefore it rises in the west, moves comparatively rapidly across the sky (in 4 h 15 min or less) and sets in the east, approximately twice a day (every 11 h 6 min). Since it is close to the surface and in an equatorial orbit, it cannot be seen above the horizon from latitudes greater than 70. The equator (sometimes referred to colloquially as "the Line") is the intersection of the Earth 's surface with the plane perpendicular to the Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the 4°.

As seen from Mars' equator, Phobos would be one-third the angular diameter of the full Moon as seen from Earth. The angular diameter of an object as seen from a given position is the "visual diameter" of the object measured as an angle EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 Observers at higher Martian latitudes would see a smaller angular diameter because they would be significantly further away from Phobos. Phobos' apparent size would actually vary by up to 45% as it passed overhead, due to its proximity to Mars' surface: for an equatorial observer, for example, Phobos would be about 0. 14° upon rising and swell to 0. 20° by the time it reaches the zenith. By comparison, the Sun would have an apparent size of about 0. The Sun (Sol is the Star at the center of the Solar System. 35° in the Martian sky.

Phobos' phases, in as much as they could be observed from Mars, take 0. 3191 days (Phobos' synodic period) to run their course, a mere 13 seconds longer than Phobos' sidereal period. The orbital period is the time taken for a given object to make one complete Orbit about another object The orbital period is the time taken for a given object to make one complete Orbit about another object

Solar transits

Main article: Transit of Phobos from Mars

Phobos transits Sun, as seen by Mars Rover Opportunity

An observer situated on the Martian surface in a position to observe Phobos would see regular transits of the moon across the Sun. A transit of Phobos across the Sun as seen from Mars takes place when Phobos passes directly between the Sun and a point on the surface of Mars obscuring A transit of Phobos across the Sun as seen from Mars takes place when Phobos passes directly between the Sun and a point on the surface of Mars obscuring MER-B ( Mars Exploration Rover - B) known as Opportunity, is the second of the two rovers of NASA 's Mars Exploration The term transit or astronomical transit has three meanings in astronomy A transit is the astronomical event that occurs when one Phobos is not large enough to cover the Sun's disk, and so cannot cause a total eclipse. An eclipse is an astronomical event that occurs when one Celestial object moves into the shadow of another Several of these transits have been photographed by the Mars Rover Opportunity. MER-B ( Mars Exploration Rover - B) known as Opportunity, is the second of the two rovers of NASA 's Mars Exploration During the transits, Phobos's shadow is cast on the surface of Mars, which has been photographed by several spacecraft.

Future destruction

Phobos' low orbit means that it will eventually be destroyed: tidal forces are lowering its orbit, currently at the rate of about 20 meters per century, and in 11 million years it will either impact the surface of Mars or (more likely) break up into a planetary ring. The tidal force is a secondary effect of the Force of Gravity and is responsible for the Tides It arises because the gravitational acceleration experienced A planetary ring is a ring of Cosmic dust and other small particles Orbiting around a Planet in a flat disc-shaped region ^[24] Given Phobos' irregular shape and assuming that it is a pile of rubble (specifically a Mohr-Coulomb body), it has been calculated that Phobos is currently stable with respect to tidal forces. In Astronomy, rubble pile is the informal name for an Asteroid that is not a Monolith, consisting instead of numerous pieces of rock that have coalesced Mohr-Coulomb theory is a Mathematical model (see Yield surface) describing the response of a material such as rubble piles or Concrete to shear stress But it is estimated that Phobos will pass the Roche Limit for a rubble pile when its orbital radius drops a little over 2,000 km to about 7,100 km. Determining the Roche limit The Roche limit depends on the rigidity of the satellite In Astronomy, rubble pile is the informal name for an Asteroid that is not a Monolith, consisting instead of numerous pieces of rock that have coalesced At this distance Phobos will likely begin to break up forming a short lived ring system around Mars. A planetary ring is a ring of Cosmic dust and other small particles Orbiting around a Planet in a flat disc-shaped region The rings themselves will then continue to spiral slowly into Mars. ^[25]

Origin

The origin of the Martian moons is still controversial. ^[26] Phobos and Deimos both have much in common with carbonaceous C-type asteroids, with spectra, albedos and densities very similar to those of C- or D-type asteroids. C-type asteroids are Carbonaceous Asteroids They are the most common variety forming around 75% of known Asteroids {Fact|date=July 2008}} and an even higher The electromagnetic (EM spectrum is the range of all possible Electromagnetic radiation frequencies The albedo of an object is the extent to which it diffusely reflects light from the sun The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different ^[10] Based on this similarity, one hypothesis is that both moons may have been captured into Martian orbit from the main asteroid belt. The asteroid belt is the region of the Solar System located roughly between the orbits of the Planets Mars and Jupiter. ^[27][28] Both moons have very circular orbits which lie almost exactly in Mars' equatorial plane, and hence a capture origin requires a mechanism for circularizing the initially highly-eccentric orbit, and adjusting its inclination into the equatorial plane, most likely by a combination of atmospheric drag and tidal forces,^[29] although it is not clear that sufficient time is available for this to occur for Deimos. In Astronomy and Navigation, the celestial sphere is an imaginary rotating Sphere of "gigantic Radius " The tidal force is a secondary effect of the Force of Gravity and is responsible for the Tides It arises because the gravitational acceleration experienced ^[26] Capture also requires dissipation of energy. The current Mars atmosphere is too thin to capture a Phobos-sized object by atmospheric braking. ^[26] Landis has pointed out that the capture could have occurred if the original body was a binary asteroid that separated due to tidal forces. Geoffrey A Landis works as a scientist and writer of Science fiction. A binary asteroid is a system of two Asteroids orbiting their common Center of mass, in analogy with Binary stars The first such system to be discovered ^[28] The main alternative hypothesis is that the moons accreted in the present position. Another hypothesis is that Mars was once surrounded by many Phobos- and Deimos-sized bodies, perhaps ejected into orbit around it by a collision with a large planetesimal. Planetesimals are solid objects thought to exist in Protoplanetary disks and in Debris disks A widely accepted theory of planet formation the so-called planetesimal ^[30]

"Hollow Phobos" claims

In the 1950 and 1960s, Phobos's unusual orbit and low density led to speculations that it might be a hollow artificial object. (Similar "hollow moon" and "hollow Earth" claims have been made). Hollow Earth is a belief that the planet Earth has a hollow interior and possibly a habitable inner surface

Around 1958, Russian astrophysicist Iosif Samuilovich Shklovsky, studying the secular acceleration of Phobos' orbital motion, suggested a "thin sheet metal" structure for Phobos, a suggestion which led to speculations that Phobos was of artificial origin. Iosif Samuilovich Shklovsky ( Ио́сиф Самуи́лович Шкло́вский) ( Glukhov, Ukraine, July 1 1916 &ndash In Astronomy, secular phenomena (which repeat too slowly to be observed if at all are contrasted with phenomena observed to repeat periodically ^[31] Shklovsky based his analysis on estimates of the upper Martian atmosphere's density, and deduced that for the weak braking effect to be able to account for the secular acceleration, Phobos had to be very light —one calculation yielded a hollow iron sphere 16 km across but less than 6 cm thick. ^[32] In a February 1960 letter to the journal Astronautics,^[33] S. Fred Singer, then science advisor to U. Siegfried Frederick Singer (born September 27, 1924 in Vienna) is an American atmospheric physicist. S. President Dwight D. Eisenhower, came out in support of Shklovsky's theory, going as far as to state that "[Phobos'] purpose would probably be to sweep up radiation in Mars' atmosphere, so that Martians could safely operate around their planet". Dwight David "Ike" Eisenhower (October 14 1890 – March 28 1969 was President of the United States from 1953 until 1961 and a five-star general A few years later, in 1963, Raymond H. Wilson Jr. , Chief of Applied Mathematics at NASA, allegedly announced to the Institute of Aerospace Sciences said that "Phobos might be a colossal base orbiting Mars", and that NASA itself was considering the possibility. The National Aeronautics and Space Administration ( NASA, ˈnæsə is an agency of the United States government, responsible for the nation's public space program An institute is a permanent Organizational body created for a certain purpose This article is about the field of research and industry for the corporation see The Aerospace Corporation Aerospace comprises the

Subsequently, however, the existence of the acceleration that had caused the claims was called into doubt,^[34] and accurate measurements of the orbit available by 1969 showed that the discrepancy did not exist. ^[35] The earlier studies had used an overestimated value of 5 cm/yr for the rate of altitude loss, which was later revised to 1. 8 cm/yr. The secular acceleration is now attributed to tidal effects, which had not been considered in the earlier studies. The density of Phobos has now been directly measured by spacecraft to be 1. 9 g/cm³, which is inconsistent with a hollow shell. In addition, images obtained by the Viking probes in the 1970s clearly showed a natural object, not an artificial one, and the "hollow Phobos" speculations have been relegated to the status of a historical curiosity. NASA 's Viking program consisted of a pair of space probes sent to Mars, Viking 1 and Viking 2.

Exploration

Past missions

Phobos has been photographed in close-up by several spacecraft whose primary mission has been to photograph Mars. The first was Mariner 9 in 1971, followed by Viking 1 in 1977, Mars Global Surveyor in 1998 and 2003, Mars Express in 2004, and Mars Reconnaissance Orbiter in 2007 and 2008. Mariner 9 (Mariner Mars '71 / Mariner-I was a NASA space probe orbiter that helped in the exploration of Mars and was part of the Mariner program. Year 1971 ( MCMLXXI) was a Common year starting on Friday (link will display full calendar of the 1971 Gregorian calendar. Viking 1 was the first of two spacecraft sent to Mars as part of NASA 's Viking program, and holds the record for the longest Mars surface mission Also 1977 (album by Ash. Year 1977 ( MCMLXXVII) was a Common year starting on Saturday (link displays The Mars Global Surveyor ( MGS) was a US Spacecraft developed by NASA and the Jet Propulsion Laboratory and launched Year 2003 ( MMIII) was a Common year starting on Wednesday of the Gregorian calendar. Mars Express is a Space exploration mission being conducted by the European Space Agency (ESA NASA 's Mars Reconnaissance Orbiter ( MRO) is a multipurpose Spacecraft designed to conduct Reconnaissance and exploration of Mars The only dedicated Phobos probes have been the Soviet Phobos 1 and Phobos 2; the first was lost en route to Mars, and the second returned some data and images before failing prior to its detailed examination of the moon. The Phobos (Фобос Fobos program was an Unmanned space mission consisting of two probes launched by the Soviet Union to study The Phobos (Фобос Fobos program was an Unmanned space mission consisting of two probes launched by the Soviet Union to study

Future missions

The Russian Space Agency is planning to launch a sample return mission to Phobos in 2009, called Phobos-Grunt. The Russian Federal Space Agency ( Russian: Федеральное космическое агентство России Federal'noe kosmicheskoe agentstvo Rossii This article is about the year For the film see 2009 Lost Memories. Phobos-Grunt ( Russian: Фобос-Грунт) is a planned Russian Sample return mission to Phobos, one of the moons of Chinese surveying equipment will be included. ^[36]

Astrium in the UK is also planning a sample return mission. EADS Astrium is an Aerospace subsidiary of the European Aeronautic Defence and Space Company (EADS based in Hampshire England The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located ^[37]

Phobos has also been proposed as an early target for a Manned mission to Mars,^[38] since a landing on Phobos would be considerably less difficult (and hence, much less expensive) than a landing on the surface of Mars itself. A human mission to visit and land on the planet Mars has long been a subject for Science fiction writers and a dream of Space exploration advocates

Named geological features

Greatly-exaggerated-color MRO view of Stickney Crater

Geological features on Phobos are named after astronomers who studied Phobos and people and places from Jonathan Swift's Gulliver's Travels. NASA 's Mars Reconnaissance Orbiter ( MRO) is a multipurpose Spacecraft designed to conduct Reconnaissance and exploration of Mars Stickney crater is the largest crater on Phobos, which is a satellite of Mars. Historically Astronomy was more concerned with the classification and description of phenomena in the sky while Astrophysics attempted to explain these phenomena Jonathan Swift (30 November 1667 Gulliver's Travels (1726 amended 1735 officially Travels into Several Remote Nations of the World in Four Parts [1] The only named ridge on Phobos is Kepler Dorsum, named after the astronomer Johannes Kepler. Johannes Kepler (ˈkɛplɚ ( December 27 1571 &ndash November 15 1630) was a German Mathematician, Astronomer Several craters have been named. [2]

Phobos in fiction

In the novel The Sands of Mars by Arthur C Clarke, Mars is terraformed when Phobos is ignited as a second sun using a meson-resonance reaction. Asaph Hall ( October 15, 1829 &ndash November 22, 1907) was an American astronomer who is most famous for having discovered Édouard Albert Roche (1820-1883 was a French scientist who is best known for his work in the field of Celestial mechanics. Stickney crater is the largest crater on Phobos, which is a satellite of Mars. Chloe Angeline Stickney Hall ( November 1 1830 &ndash July 3[[ 892]] was the wife of Astronomer Asaph Hall. David Peck Todd ( March 19, 1855 &ndash June 1 1939) was a noted American astronomer. The Sands of Mars is a Science fiction novel by Arthur C Clarke which was published in 1951, before humans had achieved space flight Sir Arthur Charles Clarke, CBE (16 December 1917–19 March 2008 was a British Science fiction Author, Inventor, and

In the novel Phobos the Robot Planet by Paul Capon, Phobos is an enormous computer, last relic of a long-vanished race of Martians. As an adjective the term "martian" is used to describe anything pertaining to the Planet Mars. Phobos learns human languages by listening to radio broadcasts, and kidnaps humans using flying saucers in order to learn about human emotions. Flying saucer is the name given to a type of Unidentified flying object (UFO with a disc- or Saucer -shaped body usually described as silver or metallic

In the novel Olympos by Dan Simmons, the Stickney crater on Phobos is a shipyard where cyborgs build a spaceship for interplanetary travel. Dan Simmons (born April 4, 1948 in Peoria, Illinois) is an American Author most widely known for his Hugo Award

In Red Mars, the first novel in the Mars Trilogy by Kim Stanley Robinson, Phobos is destroyed by impacting on Mars during the first Martian revolution. Kim Stanley Robinson (born March 23 1952) is an American Science fiction Writer, probably best known for his award-winning

In the Doom novel based on "Knee-Deep in the Dead" (the first series of levels in the video game), a marine is called to Phobos because of a distress call. Doom (officially cased DOOM) is a 1993 Computer game by Id Software that is a landmark title in the First-person shooter Throughout the story, the protagonist is teleported to Mars's other moon, Deimos.

In the Japanese manga, Sailor Moon by Naoko Takeuchi, Sailor Mars has two crows named Phobos and Deimos. is the title of a Japanese Media franchise created by Naoko Takeuchi. born March 15, 1967, is a Manga artist who lives in Tokyo, Japan. is one of the central characters in the Sailor Moon Metaseries.

In the video game Armored Core 2, Phobos is an artificial space station and super weapon created by an extinct race that inhabited Mars. A video game is a Game that involves interaction with a User interface to generate visual feedback on a video device. Armored Core 2 is a Mecha video game in the Armored Core series It is used by the leader of a mercenary group known as the Frighteners to control combat drones known as Disorder Units and is the site of the game's final mission.

On his Cords album of 1978, American synthesist Larry Fast dedicated his composition Phobos And Deimos Go To Mars to the two small Martian moons. Larry Fast (Lawrence R Fast is a Synthesizer expert and composer

In his novel Century Rain, Alastair Reynolds resurrects the idea of artificial structures inside Phobos, in his case a portal to another part of the universe. Century Rain is a 2004 noir Science fiction alternate history mystery novel by Welsh author Alastair Reynolds (ISBN Alastair Preston Reynolds (born in 1966 in Barry, Wales) is a Welsh Science fiction author.

See also

• Transit of Phobos from Mars
• Phobos and Deimos in fiction
• Phobos-Grunt mission

External links

• Phobos Profile by NASA's Solar System Exploration
• HiRISE images of Phobos
• Spacecraft images of Phobos from nineplanets
• USGS Phobos nomenclature
• Asaph Hall and the Moons of Mars
• Flight around Phobos (movie)
• Animation of Phobos

References