WE have some around mars and want to send others to other moons , but none arround our moon . Why?
2007-12-23 00:36:04 · 9 answers · asked by Gary P 2 in Science & Mathematics ➔ Astronomy & Space
Because an orbit around the moon can be unstable. The earth's gravity interferes with the satellite's orbit, and can either cause it to crash, or fling it off into open space. See the 1st link below, and read the first few paragraphs, at least.
That's doesn't mean that we don't keep putting them there. See the 2nd link. Maybe lower orbits work better? I don't know - I'm not a rocket scientist.
2007-12-23 00:50:09 · answer #1 · answered by Ralfcoder 7 · 0⤊ 0⤋
Currently, Japan and China have two spacecraft in orbit around the moon. The United States has placed spacecraft into lunar orbit during the Surveyor and Apollo programs, and in 1994 Clementine inspected the Moon from pole to pole before attempting to fly past the near-Earth asteroid Geographos. Another spacecraft called Lunar Prospector followed and made the discovery that the moon has ice in permanently shadowed regions at the poles. Although there are no active U.S. spacecraft right now in lunar orbit, there is if I'm not mistaken the ascent stage of one of the lunar landers still in orbit around the moon. That is assuming it didn't fall out of orbit and crash due to the effects of gravity and radiation pressure from sunlight. All of the others were intentionally crashed into the moon after the astronauts cut it loose then returned to Earth. We don't have any in orbit around the moon right now, but that is because NASA's attention is now directed to Mars, Mercury and the other planets. Future unmanned missions to the Moon are sure to follow, with manned landings in 2018 planned.
2007-12-23 08:49:38 · answer #2 · answered by Anonymous · 3⤊ 0⤋
It's very expensive because there are no stable lunar orbits. The Moon is too nonspherical for a spacecraft to orbit ballistically. Lunar satellites must execute frequent correction burns to remain in orbit.
2007-12-23 09:18:43 · answer #3 · answered by Anonymous · 0⤊ 0⤋
You r wrong. The China was ejected a satelite named 'Chang Er 1' to round the moon. This is artificial satelite. For the true celestial satelite, I think because the moon's gravitational potential is weak and limited so it is difficult to capture an objects as it's satelite.
2007-12-23 08:46:45 · answer #4 · answered by Anonymous · 0⤊ 3⤋
Your facts are wrong. There are currently two satellites in orbit around the Moon, one Chinese and one Japanese.
2007-12-23 08:54:33 · answer #5 · answered by GeoffG 7 · 0⤊ 0⤋
Those planets are far we can easily fly to the moon and take scientific readings
2007-12-23 13:06:36 · answer #6 · answered by Derchin 6 · 0⤊ 0⤋
Ah, but there is:
http://www.usatoday.com/tech/science/space/2007-11-05-china-satellite-moon_N.htm?csp=34
2007-12-23 08:41:49 · answer #7 · answered by Jason 6 · 4⤊ 0⤋
because we can travel to our moon by ourselves but a satelite would probably cost us less money than sending up ships.
2007-12-23 08:38:49 · answer #8 · answered by Dan B 2 · 0⤊ 4⤋
wow there is one. lol
BUT THAT IS GOOD TO KNOW, IF I GO TO THE MOON, I CAN NOW GET DIRECT TV !!!!!
2007-12-23 08:45:28 · answer #9 · answered by jason h 2 · 0⤊ 1⤋