If they move at different rates, is it due to their individual mass/gravity?
2007-03-07 07:41:59 · 8 answers · asked by cameronscami 2 in Science & Mathematics ➔ Astronomy & Space
No. In general, the planets closer to the sun move faster. Mercury near 30 miles / sec, Neptune about 3 miles /sec.
http://www.enchantedlearning.com/subjects/astronomy/planets/
KEPLER'S SECOND LAW OF PLANETARY MOTION
Kepler's Second Law of Planetary Motion states that a line from a planet to the sun will sweep out equal areas in equal times. The planet moves more slowly when it is farther from the sun and faster when it is near it. (This is equivalent to the conservation of angular momentum.)
2007-03-07 07:50:01 · answer #1 · answered by DanE 7 · 4⤊ 0⤋
The force of gravity is inversely proportional to the square of the distance. So to overcome gravity and achieve a stable orbit a planet twice as close to the sun must move four times as fast. The mass of the planet is negligible in this calculation. Planets further from the sun not only have further to travel but also move much slower.
2007-03-07 08:19:12 · answer #2 · answered by trewornan 2 · 2⤊ 0⤋
The gravity/distance explanations are correct -- closer = faster, owing to the strength of the gravity field closer in.
Think of it this way. Earth is orbiting at the one perfect speed to maintain its orbit. If it slowed down, its orbit would decay, it would be overcome by gravity, and it would tumble into the sun. Since Venus isn't tumbling into the sun it must be moving faster.
If Earth sped up to the speed of Venus -- way out here where sun's gravity is weaker -- it would open up more distance from the sun, and start heading on out of the solar system. It would not settle into Mars' orbit, it would be too fast for that.
2007-03-07 08:43:05 · answer #3 · answered by KevinStud99 6 · 0⤊ 0⤋
They absolutely do NOT move at the same rate whatsoever, whether you mean the angular or linear (tangential) velocity.
The rate at which they move is based upon how distant they are from the sun. Basically, they move at a rate such that they experiece centripetal acceleration that matches the gravitational attraction between them and the sun. Thus, their size/mass has nothing at all to do with the rate at which they orbit the sun, but only is affected by how far away they are from the sun.
2007-03-07 07:52:27 · answer #4 · answered by Anonymous · 4⤊ 0⤋
Dan E got it right. Read about Kepler's laws.
It is worth reading the history of guys like Copernicus, Kepler, Brahe and Galileo. Prior to these guys, nobody had the least comprehension of the order of the Solra System or the cosmos.
And the sad thing is that most people these days still have no idea. cripes, from what I have seen on this site, most people do not even know what causes the phases of the moon. So, most people are living 500 years in the past.
2007-03-07 07:55:32 · answer #5 · answered by nick s 6 · 3⤊ 0⤋
I disagree that mass has nothing to do with it, it may be a very small factor, but it most certainly has an effect. If Mercury were in Jupiter's place, it could go slower than Jupiter and remain in oribt, because the pull between it and the sun would be far weaker.
2007-03-07 08:43:21 · answer #6 · answered by Anonymous · 0⤊ 0⤋
good question...i would think it would be at the same rate, just at different distances so each planet's year is longer. but the gravitational pull is probably different for each planet so it may be different rates...jeez now u got me wondering!
2007-03-07 07:50:32 · answer #7 · answered by Anonymous · 0⤊ 6⤋
Yes sir!!!!!!!!!!!! i mean mam!!!!!
2007-03-07 07:51:49 · answer #8 · answered by luv 2 shop! 1 · 0⤊ 4⤋