Moon
hideThe Moon is Earth's only natural satellite and the fifth largest satellite in the Solar System. The average centre-to-centre distance from the Earth to the Moon is 384,403 km, about thirty times the diameter of the Earth. The common centre of mass of the system (the barycentre) is located about 1,700 km—a quarter the Earth's radius—beneath the surface of the Earth. The Moon makes a complete orbit around the Earth every 27.3 days (the orbital period), and the periodic variations in the geometry of the Earth–Moon–Sun system are responsible for the phases of the moon, which repeat every 29.5 days (the synodic period).
The Moon's diameter is 3,474 km, a little more than a quarter of that of the Earth. Thus, the Moon's surface area is less than a tenth that of the Earth (about a quarter the Earth's land area, approximately as large as Russia, Canada, and the United States combined), and its volume is about 2 percent that of Earth. The pull of gravity at its surface is about 17 percent of that at the Earth's surface.
The Moon is the only celestial body to which humans have traveled and upon which humans have performed a manned landing. While the Soviet Union's Luna program was the first to reach the Moon with unmanned spacecraft, the NASA Apollo program by the United States achieved the only manned missions to date, beginning with the first manned lunar mission by Apollo 8 in 1968, and six manned lunar landings between 1969 and 1972- the first being Apollo 11 in 1969. Human exploration of the Moon temporarily ceased with the conclusion of the Apollo program, although a few robotic landers and orbiters have been sent to the Moon since that time. The U.S. has committed to return to the moon by 2018.
For more information about Moon, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with moon
Successful Flight Through Enceladus Plume (w/ Video)
Space & Earth / Space Exploration
Nov 04, 2009 |
4.7 / 5 (3) |
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(PhysOrg.com) -- Cassini has started sending data back from its Nov. 2 flyby of Saturn's moon Enceladus.
Fantastic Voyage
Space & Earth / Space Exploration
Nov 02, 2009 |
4.8 / 5 (19) |
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By travelling to the outer solar system, the two Voyager spacecraft allowed us to see amazing details of far-distant planets and moons.
STAR TRAK for November: Mars is prominent again
Space & Earth / Space Exploration
Nov 02, 2009 |
4 / 5 (2) |
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(PhysOrg.com) -- Pumpkin-colored Mars will return to prominence during November, rising shortly before midnight at the beginning of the month and more than two hours earlier by month's end. The orange planet ...
2 parachutes malfunctioned in NASA test flight
Space & Earth / Space Exploration
Oct 30, 2009 |
4.8 / 5 (6) |
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(AP) -- Two of three parachutes malfunctioned in the test flight of a prototype moon rocket earlier this week, causing major damage to the booster, NASA said Friday.
NASA: Booster rocket damaged in test flight
Space & Earth / Space Exploration
Oct 29, 2009 |
3 / 5 (6) |
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(AP) -- NASA says the booster rocket used in a test flight was badly dented when it fell into the Atlantic.
Icebreaker: Scientist brings out big gun to explore behavior of ice in planetary collisions
Space & Earth / Space Exploration
Oct 29, 2009 |
not rated yet |
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(PhysOrg.com) -- Every month, Sarah Stewart-Mukhopadhyay fires her 20-foot gun in the basement of Harvard's Hoffman Lab, sending shivers through the concrete and steel structure that can be picked up by seismometers ...
New Celestial Map Gives Directions for GPS
Space & Earth / Space Exploration
Oct 29, 2009 |
4.5 / 5 (4) |
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(PhysOrg.com) -- Many of us have been rescued from unfamiliar territory by directions from a Global Positioning System (GPS) navigator. GPS satellites send signals to a receiver in your GPS navigator, which ...
NASA's Ares I-X moon rocket makes first test flight
Space & Earth / Space Exploration
Oct 28, 2009 |
4.5 / 5 (25) |
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(PhysOrg.com) -- NASA's Ares I-X test rocket lifted off at 11:30 a.m. EDT Wednesday from NASA's Kennedy Space Center in Florida for a two-minute powered flight.
Robot Armada Might Scale New Worlds
Space & Earth / Space Exploration
Oct 28, 2009 |
4.3 / 5 (11) |
5
(PhysOrg.com) -- An armada of robots may one day fly above the mountain tops of Saturn's moon Titan, cross its vast dunes and sail in its liquid lakes.
NASA tries 2nd time to launch experimental rocket
Space & Earth / Space Exploration
Oct 28, 2009 |
5 / 5 (2) |
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(AP) -- Bad weather was interfering with NASA's attempt to launch a new, experimental rocket for the second day in a row early Wednesday.
Detecting Life-Friendly Moons
Space & Earth / Space Exploration
Oct 26, 2009 |
4.8 / 5 (11) |
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The search for life-friendly real estate around distant stars doesn't have to be limited to planets. New research shows that habitable exomoons can be detected with a new method using current technology.
Bad weather could interfere with NASA test flight
Space & Earth / Space Exploration
Oct 26, 2009 |
5 / 5 (1) |
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(AP) -- NASA's newest rocket is on the verge of blasting off on a test flight.
NASA is 'go' for crucial rocket test
Space & Earth / Space Exploration
Oct 25, 2009 |
4.4 / 5 (7) |
5
NASA is set to blast off a prototype rocket on Tuesday that carries hopes of returning humans to the Moon, and for the first time to Mars, despite deep uncertainty about the program's future.
Panel says NASA should skip moon, fly elsewhere (Update)
Space & Earth / Space Exploration
Oct 23, 2009 |
3.3 / 5 (12) |
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(AP) -- NASA needs to make a major detour on its grand plans to return astronauts to the moon, a special independent panel told the White House Thursday.
Eyes to the skies for the 'Galilean Nights'
Oct 22, 2009 |
4 / 5 (3) |
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Astronomers around the world are gearing up for three days of intense sky-watching in honour of Galileo, whose observations 400 years ago revolutionised our understanding of the cosmos.
