Encyclopedia - Iapetus Moon: Encyclopedia Ii - Iapetus Moon - Orbit
The orbit of Iapetus is somewhat unusual. Although it is one of Saturn's largest moons, it orbits much farther from Saturn than the next ...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Orbit
The Moon makes a complete orbit about the Earth approximately once every 28 days. Each hour the Moon moves relative to the stars by an am...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Orbit
The Moon makes a complete orbit about once every 28 days. Each hour the Moon moves relative to the stars by an amount roughly equal to it...   » Read the article

Encyclopedia - Moon: Encyclopedia - Moon
The Moon as seen from Earth Ammonia Carbon dioxide The Moon is the planet Earth's only natural satellite. It has no formal name other tha...   » Read the article

Encyclopedia - Triton Moon: Encyclopedia Ii - Triton Moon - Orbit
Triton is unique among all large moons in the solar system for its retrograde orbit around the planet (i.e., it orbits in a direction opp...   » Read the article

Encyclopedia - Jupiter Icy Moons Orbiter: Encyclopedia Ii - Jupiter Icy Moons Orbiter - The Jimo Spacecraft
JIMO was to have a large number of revolutionary features. Throughout its main voyage to the Jupiter moons, it was to be propelled by an ...   » Read the article

Encyclopedia - Phoebe Moon: Encyclopedia Ii - Phoebe Moon - Orbital Characteristics
For more than 100 years, Phoebe was Saturn's outermost known moon, until the discovery of several smaller moons in 2000. Phoebe is almost...   » Read the article

Encyclopedia - Janus Moon: Encyclopedia Ii - Janus Moon - Discovery And Orbit
Janus occupies essentially the same orbit as the moon Epimetheus. This caused some confusion for astronomers, who assumed that there was ...   » Read the article

Encyclopedia - 2003 Ub313: Encyclopedia - 2003 Ub313
2003 UB313 (center) and moon (right of center). Keck Observatory. 2003 UB313 is a trans-Neptunian object (TNO) which California astronome...   » Read the article

Encyclopedia - Pluto: Encyclopedia - Pluto
Pluto is the ninth planet in the solar system. Discovered in 1930 and immediately classified as a planet, its status is currently under d...   » Read the article

Encyclopedia - Phobos Moon: Encyclopedia Ii - Phobos Moon - Orbital Characteristics
Phobos orbits Mars below the synchronous orbit radius, meaning that it moves around Mars faster than Mars itself rotates. Therefore it ri...   » Read the article

Encyclopedia - Apollo 8: Encyclopedia - Apollo 8
Apollo 8 was the second manned mission of the Apollo space program, in which Commander Frank Borman, Command Module Pilot James Lovell an...   » Read the article

Encyclopedia - 2003 El61: Encyclopedia - 2003 El61
2003 EL61 (also written 2003 EL61), nicknamed "Santa" (non-official designation), is a very large and unusual Kuiper belt object recently...   » Read the article

Encyclopedia - Orbital Node: Encyclopedia - Orbital Node
An orbital node is one of the two points where an inclined orbit crosses a plane of reference (e.g. the equator for geocentric orbits, th...   » Read the article

Encyclopedia - Cassini-huygens: Encyclopedia - Cassini-huygens
Cassini-Huygens is a joint NASA/ESA/ASI unmanned space mission intended to study Saturn and its moons. The spacecraft consists of two mai...   » Read the article

Encyclopedia - Janus Moon: Encyclopedia Ii - Janus Moon - Orbital Relationship Between Epimetheus And Janus
Janus and Epimetheus are "co-orbital". Janus' orbital radius from Saturn is currently 151,472 km and Epimetheus' orbital radius is 151,42...   » Read the article

Encyclopedia - Epimetheus Moon: Encyclopedia Ii - Epimetheus Moon - Orbital Relationship Between Epimetheus And Janus
Epimetheus and Janus are co-orbital: Janus' orbital radius from Saturn is currently 151,472 km and Epimetheus' orbital radius is 151,422 ...   » Read the article

Encyclopedia - Epimetheus Moon: Encyclopedia Ii - Epimetheus Moon - Discovery
Epimetheus occupies essentially the same orbit as the moon Janus. Astronomers assumed that there was only one body in that orbit, and acc...   » Read the article

Encyclopedia - Janus Moon: Encyclopedia Ii - Janus Moon - Name
Janus is named after Janus, the two-faced Roman god. Although the name was informally proposed soon after the initial 1966 discovery, it ...   » Read the article

Encyclopedia - Phoebe Moon: Encyclopedia Ii - Phoebe Moon - Physical Characteristics
Phoebe is roughly spherical and has a diameter of 220 kilometres (about 137 miles), which is equal to about one-fifteenth of the diameter...   » Read the article

Encyclopedia - Phoebe Moon: Encyclopedia Ii - Phoebe Moon - Name
The moon is named after Phoebe, a Titan in Greek mythology. It is also designated Saturn IX. The IAU nomenclature standards have stated t...   » Read the article

Encyclopedia - Phoebe Moon: Encyclopedia Ii - Phoebe Moon - Spacecraft Flybys
The Voyager 2 spacecraft passed by Phoebe in September 1981, although the 2.2 Gm (2.2 million kilometres) distance and low resolution mea...   » Read the article

Encyclopedia - Iapetus Moon: Encyclopedia Ii - Iapetus Moon - Physical Characteristics
The low density of Iapetus indicates that it is primarily composed of ice, with only a small amount of rocky materials. Furthermore, the ...   » Read the article

Encyclopedia - Iapetus Moon: Encyclopedia Ii - Iapetus Moon - Speculation That Iapetus Is Artificial
The oddness of Iapetus has occasionally led to speculation that it may be an artificial construction by extraterrestrials. In 1980, Donal...   » Read the article

Encyclopedia - Iapetus Moon: Encyclopedia Ii - Iapetus Moon - Name
Iapetus is named after the mythological Iapetus. It is also designated Saturn VIII. Giovanni Cassini named the four moons he discovered (...   » Read the article

Encyclopedia - Phobos Moon: Encyclopedia Ii - Phobos Moon - Phobos In Fiction
The first episode of the computer and video game Doom takes place in a UAC base on Phobos. Phobos also featured in Kim Stanley Robinson's...   » Read the article

Encyclopedia - Triton Moon: Encyclopedia Ii - Triton Moon - Planetary Geology
Triton has a similar size, density, and chemical composition to that of Pluto, and upon verifying the eccentric orbit of Pluto that cross...   » Read the article

Encyclopedia - Triton Moon: Encyclopedia Ii - Triton Moon - Seasons
The axis of rotation of Triton is highly irregular inclined 157 degrees in relation to the axis of Neptune, and 130 degrees in respect to...   » Read the article

Encyclopedia - Epimetheus Moon: Encyclopedia Ii - Epimetheus Moon - Physical Characteristics
There are several Epimethean craters larger than 30 km in diameter, as well as both large and small ridges and grooves. The extensive cra...   » Read the article

Encyclopedia - Triton Moon: Encyclopedia Ii - Triton Moon - Potential For Life
Like the atmosphere of Titan, Triton's atmosphere is composed of nitrogen and methane. Nitrogen is also the principal constituent of Eart...   » Read the article

Encyclopedia - Phobos Moon: Encyclopedia Ii - Phobos Moon - Hollow Phobos Claims
Around 1958, the distinguished Russian astrophysicist Iosif Samuilovich Shklovsky, studying the secular acceleration of Phobos' orbital m...   » Read the article

Encyclopedia - Triton Moon: Encyclopedia Ii - Triton Moon - Name
Triton is named after Triton (from the Greek Τρίτων,son of Poseidon. The name was proposed by Camille Flammarion in 1880. It is per...   » Read the article

Encyclopedia - Phobos Moon: Encyclopedia Ii - Phobos Moon - Discovery
Phobos was discovered by American astronomer Asaph Hall on August 18, 1877 at the US Naval Observatory in Washington, D.C at about 09:14 ...   » Read the article

Encyclopedia - Triton Moon: Encyclopedia Ii - Triton Moon - History Of Observation And Exploration
In 1820, William Lassell started to make mirrors for his telescope and in 1844, made better mirrors that allowed him to discover the plan...   » Read the article

Encyclopedia - Phobos Moon: Encyclopedia Ii - Phobos Moon - Physical Characteristics
Phobos is a dark body that appears to be composed of C-type surface materials. It is similar to the C-type (blackish carbonaceous chondri...   » Read the article

Encyclopedia - Saturn's Natural Satellites: Encyclopedia Ii - Saturn's Natural Satellites - Introduction
Saturn is currently known to have 47 moons, many of which were discovered very recently, and 3 suspected moons. However, a precise number...   » Read the article

Encyclopedia - Natural Satellite: Encyclopedia Ii - Natural Satellite - Orbital Characteristics
Most moons in the solar system are tidally locked to their primaries, meaning that one side of the moon is always turned toward the plane...   » Read the article

Encyclopedia - 2003 Ub313: Encyclopedia Ii - 2003 Ub313 - Classification
2003 UB313 is classified as a scattered disk object (SDO), a category of TNO which are believed to have been "scattered" from the Kuiper ...   » Read the article

Encyclopedia - Natural Satellite: Encyclopedia Ii - Natural Satellite - Moons Of The Solar System
The largest moons in the solar system (those bigger than about 3000 km across) are Earth's Moon, Jupiter's Galilean moons Io, Europa, Gan...   » Read the article

Encyclopedia - 2003 Ub313: Encyclopedia Ii - 2003 Ub313 - Name
The object currently has the provisional designation 2003 UB313, granted automatically according to the IAU's naming protocols for minor ...   » Read the article

Encyclopedia - T/space: Encyclopedia Ii - T/space - Cxv Proposal
t/Space is currently working on designs for an air-launched four-person capsule termed the Crew Transfer Vehicle, or CXV. In contrast to ...   » Read the article

Encyclopedia - Saturn's Natural Satellites: Encyclopedia Ii - Saturn's Natural Satellites - Table Of Known Moons
The Saturnian moons are listed here by orbital period, from shortest to longest. Moons massive enough for their surfaces to have collapse...   » Read the article

Encyclopedia - Pluto: Encyclopedia Ii - Pluto - Orbit
Pluto's orbit is unlike those of the other planets. It is highly inclined above the plane of the ecliptic, and highly eccentric (non-circ...   » Read the article

Encyclopedia - 2003 Ub313: Encyclopedia Ii - 2003 Ub313 - Surface
The discovery team followed up their initial identification of 2003 UB313 with spectroscopic observations made at the 8 m Gemini North Te...   » Read the article

Encyclopedia - Saturn's Natural Satellites: Encyclopedia Ii - Saturn's Natural Satellites - Grouping The Moons
Although the borders may be somewhat nebulous, Saturn's moons can be divided into eight groups. Saturn's natural satellites - The ring s...   » Read the article

Encyclopedia - 2003 Ub313: Encyclopedia Ii - 2003 Ub313 - Discovery
2003 UB313 was discovered by the team of Michael Brown, Chad Trujillo, and David Rabinowitz on January 5, 2005 from images taken on Octob...   » Read the article

Encyclopedia - 2003 Ub313: Encyclopedia Ii - 2003 Ub313 - Size
The brightness of a solar system object depends both on its size and the amount of light it reflects (its albedo). If the distance to an ...   » Read the article

Encyclopedia - Pluto: Encyclopedia Ii - Pluto - Pluto's Moons
Pluto has three known natural satellites: Charon, first identified in 1978, and two smaller, as yet unnamed moons discovered in 2005. Pl...   » Read the article

Encyclopedia - Pluto: Encyclopedia Ii - Pluto - Exploration Of Pluto
Little is known about Pluto because of its great distance from Earth and because no exploratory spacecraft have visited Pluto yet. The Vo...   » Read the article

Encyclopedia - Pluto: Encyclopedia Ii - Pluto - Discovery And Naming
Pluto was discovered by the astronomer Clyde Tombaugh at the Lowell Observatory in Arizona on February 18, 1930 after an extensive search...   » Read the article

Encyclopedia - Pluto: Encyclopedia Ii - Pluto - The Pluto Debate
Pluto - Planet X?. The planet Pluto was originally discovered in 1930 in the course of a search for a body sufficiently massive to acco...   » Read the article

Encyclopedia - Pluto: Encyclopedia Ii - Pluto - Physical Characteristics
More than 75 years after its discovery, many facts about Pluto remain unknown, mainly due to the fact that it is the only planet that has...   » Read the article

Encyclopedia - Venus: Encyclopedia Ii - Venus - Orbital Characteristics
Venus - Orbit. Although all planets' orbits are elliptical, Venus's orbit is the closest to circular, with an eccentricity of less than...   » Read the article

Encyclopedia - Space Burial: Encyclopedia Ii - Space Burial - Famous People Buried In Space
Space burial - Launched to Earth orbit on April 21 1997. Gene Roddenberry (August 19, 1921 - October 24, 1991), creator of Star Trek. ...   » Read the article

Encyclopedia - Venus: Encyclopedia Ii - Venus - Observations And Explorations Of Venus
Venus sky movement patterns have been observed several times within the past 4000 years by a number of people, including the Greeks. For ...   » Read the article

Encyclopedia - 2003 El61: Encyclopedia Ii - 2003 El61 - Size And Composition
The total mass of the 2003 EL61 system can be determined from the orbits of its satellites by Kepler's third law. It turns out to be 4.2�...   » Read the article

Encyclopedia - Hipparchus Astronomer: Encyclopedia Ii - Hipparchus Astronomer - Geometry And Trigonometry
Hipparchus is recognised as the first mathematician who compiled a trigonometry table, which he needed when computing the eccentricity of...   » Read the article

Encyclopedia - Apollo 8: Encyclopedia Ii - Apollo 8 - Mission Parameters
Apollo 8 - Earth parking orbit. Perigee: 112.8 mi (181.5 km) Apogee: 118.9 mi (191.3 km) Inclination: 32.51° Period: 88.17 min Apol...   » Read the article

Encyclopedia - Hipparchus Astronomer: Encyclopedia Ii - Hipparchus Astronomer - Lunar And Solar Theory
Hipparchus astronomer - Motion of the Moon. Hipparchus also studied the motion of the Moon and confirmed the accurate values for some p...   » Read the article

Encyclopedia - Space Burial: Encyclopedia Ii - Space Burial - Outlook
Currently, only one company, Space Services Inc., offers space burials. Space Services took over the assets of Celestis, Inc., which laun...   » Read the article

Encyclopedia - Space Burial: Encyclopedia Ii - Space Burial - Technical And Economical Aspects
The effort and cost of launching an object into space is very high. Furthermore, the cost is directly related to the payload, i.e. the ma...   » Read the article

Encyclopedia - Space Burial: Encyclopedia Ii - Space Burial - Outlook
Currently, only one company, Space Services Inc., offers space burials. Space Services took over the assets of Celestis, Inc., which laun...   » Read the article

Encyclopedia - Space Burial: Encyclopedia Ii - Space Burial - Famous People Buried In Space
Space burial - Launched to Earth orbit on April 21 1997. Gene Roddenberry (August 19, 1921 - October 24, 1991), creator of Star Trek. ...   » Read the article

Encyclopedia - Space Burial: Encyclopedia Ii - Space Burial - History
The practice of space burials is a very recent practice due to the technical difficulties involved in launching an object into space. The...   » Read the article

Encyclopedia - Space Burial: Encyclopedia Ii - Space Burial - History
The practice of space burials is a very recent practice due to the technical difficulties involved in launching an object into space. The...   » Read the article

Encyclopedia - Venus: Encyclopedia Ii - Venus - Physical Characteristics
Venus - Atmosphere. Venus has an atmosphere consisting mainly of carbon dioxide and a small amount of nitrogen, with a pressure at the ...   » Read the article

Encyclopedia - Venus: Encyclopedia Ii - Venus - Life At Venus
Space probes in the 1960's made it pretty clear that the surface of Venus is far too hot to support life as we know it. However, the clou...   » Read the article

Encyclopedia - Venus: Encyclopedia Ii - Venus - Venus In Human Culture
Venus - Mythology. The pentagram has long been associated with the planet Venus and the worship of the goddess Venus, or her equivalent...   » Read the article

Encyclopedia - 2003 El61: Encyclopedia Ii - 2003 El61 - Discovery Controversy
José Luis Ortiz Moreno, an astronomer at the Sierra Nevada Observatory in Spain, and colleagues Francisco José Aceituno Castro and Pabl...   » Read the article

Encyclopedia - Hipparchus Astronomer: Encyclopedia Ii - Hipparchus Astronomer - Life And Work
Most of what is known about Hipparchus comes from Ptolemy's (2nd century) Almagest ("the great treatise"; ed. [Toomer 1981]), with additi...   » Read the article

Encyclopedia - Hipparchus Astronomer: Encyclopedia Ii - Hipparchus Astronomer - Babylonian Sources
Many of the works of Greek scientists - mathematicians, astronomers, geographers - have been preserved up to the present time, or some as...   » Read the article

Encyclopedia - Hipparchus Astronomer: Encyclopedia Ii - Hipparchus Astronomer - Astronomical Instruments And Astrometry
Hipparchus is credited with the invention or improvement of several astronomical instruments, which were used for a long time for naked-e...   » Read the article

Encyclopedia - Hipparchus Astronomer: Encyclopedia Ii - Hipparchus Astronomer - Star Catalogue
After that, in 135 BC, enthusiastic about a nova in the constellation of Scorpius, he measured with an equatorial armillary sphere eclipt...   » Read the article

Encyclopedia - Hipparchus Astronomer: Encyclopedia Ii - Hipparchus Astronomer - Precession Of The Equinoxes 146 Bc-130 Bc
Hipparchus is perhaps most famous for having been the first to measure the precession of the equinoxes. There is some suggestion that the...   » Read the article

Encyclopedia - Space Burial: Encyclopedia Ii - Space Burial - Technical And Economical Aspects
The effort and cost of launching an object into space is very high. Furthermore, the cost is directly related to the payload, i.e. the ma...   » Read the article

Encyclopedia - Apollo 8: Encyclopedia Ii - Apollo 8 - Planning
On December 22, 1966, NASA announced the crew for the third manned Apollo flight: Frank Borman, Michael Collins and Bill Anders. Collins ...   » Read the article

Encyclopedia - Apollo 8: Encyclopedia Ii - Apollo 8 - Historical Importance
Apollo 8 came at the end of 1968, a year that had seen much upheaval around the world. Soviet tanks had put a stop to the Prague Spring i...   » Read the article

Encyclopedia - Apollo 8: Encyclopedia Ii - Apollo 8 - The Saturn V
The Saturn V rocket used by Apollo 8 was designated SA-503, the third flight model. When it was erected in the Vertical Assembly Building...   » Read the article

Encyclopedia - Apollo 8: Encyclopedia Ii - Apollo 8 - The Mission
Apollo 8 - Launch and trans-lunar injection. Apollo 8 launched at 7:51:00 a.m. Eastern Standard Time on December 21, 1968. The entire l...   » Read the article

Encyclopedia - Project Apollo: Encyclopedia Ii - Project Apollo - Missions
Image:Moon map showing Apollo missions.PNG The Apollo program used four types of launch vehicles: Little Joe II - unmanned suborbital la...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Occultation Of Stars
During the year, the Moon occults - or passes over and hides for a period of time - stars and planets. Because the Moon is close to Earth...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Human Understanding Of The Moon
Moon - Myth and folk culture. Main article: Moon (mythology) Moon - The Moon as muse. Main article: Moon in art and literature Th...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Earth & Moon
Moon - Tidal Effects. The tides on Earth are generated by the Moon's gravitation (see tide and tidal force for a more detailed discussi...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Origin And History
The inclination of the Moon's orbit makes it implausible that the Moon formed along with the Earth or was captured later; its origin is t...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Exploration Of The Moon
The first leap in Lunar observation was caused by the invention of the telescope. Especially Galileo Galilei made good use of this new in...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - The Two Sides Of The Moon
The far side is sometimes called the "dark side". In this case "dark" means "unknown and hidden" and not "lacking light" as implied by th...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Observation Of The Moon
During the brightest full moons, the Moon can have an apparent magnitude of about −12.6. For comparison, the Sun has an apparent magnit...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Human Understanding Of The Moon
Moon - Myth and folk culture. Moon - The Moon as muse. The Moon has been the subject of many works of art and literature and the insp...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Occultation Of Stars
During the year, the moon occults sometimes stars and planets. Because the moon is close to the earth, occultations of stars are not vis...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Legal Status
Though several flags of the Soviet Union and the United States have been symbolically planted on the moon, the Russian and U.S. governmen...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Earth & Moon
The tides on Earth are generated by the Moon's gravitation (see tide and tidal force for a more detailed discussion). There are two tidal...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Physical Characteristics
Moon - Composition. More than 4.5 billion years ago, the surface of the Moon was a liquid magma ocean. Scientists think that one compon...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Exploration Of The Moon
The first leap in Lunar observation was caused by the invention of the telescope. Especially Galileo Galilei made good use of this new in...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - The Two Sides
The far side is sometimes called the "dark side". In this case "dark" means "unknown and hidden" and not "lacking light" as implied by th...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Origin And History
The inclination of the Moon's orbit makes it implausible that the Moon formed along with the Earth or was captured later; its origin is t...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Eclipses
The angular diameters of the Moon and the Sun as seen from Earth overlap in their variation, so that both total and annular solar eclipse...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Observation Of The Moon
During the brightest full moons, the Moon can have an apparent magnitude of about −12.6. For comparison, the Sun has an apparent magnit...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Legal Status
Though several flags of the Soviet Union and the United States have been symbolically planted on the moon, the Russian and U.S. governmen...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Physical Characteristics
Moon - Composition. More than 4.5 billion years ago, the surface of the Moon was a liquid magma ocean. Scientists think that one compon...   » Read the article

Encyclopedia - Moon: Encyclopedia Ii - Moon - Eclipses
The angular diameters of the Moon and the Sun as seen from Earth overlap in their variation, so that both total and annular solar eclipse...   » Read the article