escape velocity for the earth refers to the minimum speed an object must have to leave the earth and never return. The escape velocity for the moon is about one-fifth what it is for the earth due to the Moon's smaller mass. Explain why the moon has practically no atmosphere.
2007-04-12 15:28:15 · 6 answers · asked by uglyshrek6 1 in Science & Mathematics ➔ Astronomy & Space
On Earth, our atmosphere is held in place by gravity. Atoms such as loose Hydrogen (H2) are not heavy enough to be maintained in our atmosphere due to gravity and therefore disperse (the majority, anyway) into space. On the other hand, Oxygen and Nitrogen molecules are heavy enough to be held in Earth's orbit due to Earth's gravity.
On the other hand, the moon is small and has low gravity. If there existed a source of gas on the moon, the molecules would not be heavy enough to be maintained in the moon's orbit. Since there is no activity on the moon, and it's basically a piece of rock with no volcanic, geological or other activity, there is no source of gasses. So even if there was higher gravity on the moon, without a source of gasses there would be no atmosphere.
On Jupiter's moon Io, which still has some kind of geological activity, there are volcanos of Sulfur dioxide and other gasses that erupt. Io also has a low level of gravity, however, nearby the sulfur dioxide plumes there is a formation of a 'localized' atmosphere until the gas dissipates. The moon in general has a very think atmosphere formed by the gas, proving the above points.
2007-04-12 15:38:44 · answer #1 · answered by FourWheelDave 3 · 1⤊ 0⤋
The speed of those remaining molecules enable them to easily reach a height where they are swept away by the solar wind. Escape speed (velocity) is that speed at the surface of a planet, required to reach the edge of the universe, with no remaining kinetic energy.
2007-04-12 19:03:38 · answer #2 · answered by CLICKHEREx 5 · 0⤊ 0⤋
get away velocity is the (theoretical) velocity an merchandise could desire to be vacationing at initially whilst it left the exterior of the earth to triumph over acceleration by gravity. get away velocity isn't the fee an merchandise ought to be going because it truly is leaving the ambience. that's assuming there are not the different forces performing on it, different than for its weight (gravity). in case you're taking a ball and throw it quickly upwards, as quickly because it leaves your hand gravity starts off accelerating the ball returned in direction of the floor. initially you notice this by fact the ball decelerating mutually as moving upwards, yet at last it ought to have bogged down lots it is going to become table sure, on the suited of its course. After this, of course it starts off accelerating backtrack returned. get away velocity is how briskly you're able to ought to throw that ball so as that it is not in any respect bogged down lots that it stops and starts off coming backtrack returned. the occasion you gave with your hand is fantastic. in case you have been helping the ball (or stone) all the way out you need to circulate as sluggish as you liked. the substantial difference that's which you're constantly offering an upwards tension to triumph over gravity, so get away velocity would not prepare.
2016-12-29 06:07:46 · answer #3 · answered by ? 3 · 0⤊ 0⤋
All the gas molecules long ago reached escape velocity just by being warmed by sunlight. Heat is random motion of molecules.
2007-04-12 15:32:46 · answer #4 · answered by campbelp2002 7 · 2⤊ 1⤋
The Moon is Geologically inactive and no new gases are released from its core.
2007-04-12 15:31:43 · answer #5 · answered by novangelis 7 · 1⤊ 2⤋
I don't know why someone gave the person above me a thumbs down...they are correct.
2007-04-12 15:35:28 · answer #6 · answered by star2_watch 3 · 2⤊ 1⤋