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JBash
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Even the Moon is moving away from the Earth each year by approximately 1 inch. What keeps the planets in their alignment? Why aren't they either being drawn into the Sun or pushed away(like our moon to Earth)?
JBash said:Even the Moon is moving away from the Earth each year by approximately 1 inch. What keeps the planets in their alignment? Why aren't they either being drawn into the Sun or pushed away(like our moon to Earth)?
I like the simple, anthropic principle answer: the planets are in orbits that are stable on the timeframe of at least 4 billion years because if they weren't, they'd have already collided with other objects and wouldn't be here.SpaceTiger said:Despite these motions, however, the planets do seem to stay relatively well aligned over billions of years. The reason for this is still, I think, a matter of debate, but it appears that we lucked out --
Ehh, maybe its just wishful thinking, but I'd like to wait a while on that - for now a big part of the reason we're finding solar systems that aren't like ours is that we aren't capable of finding solar systems like ours.that is, the other planetary systems we've observed so far are considerably less organized and convenient for the formation of life.
russ_watters said:I like the simple, anthropic principle answer: the planets are in orbits that are stable on the timeframe of at least 4 billion years because if they weren't, they'd have already collided with other objects and wouldn't be here.
Ehh, maybe its just wishful thinking, but I'd like to wait a while on that - for now a big part of the reason we're finding solar systems that aren't like ours is that we aren't capable of finding solar systems like ours.
coltseaversuk said:I understand how planets are 'held' to keep their shape of orbit, but what force is keeping it pushing forward?
coltseaversuk said:Ok I'm a bit closer to understanding it (I'm an Electrical Engineer not a Physicist). I've read the inertia article, so the planets are in inertial motion now yes? So did something have to accelerate them initially?
coltseaversuk said:Ok I'm a bit closer to understanding it (I'm an Electrical Engineer not a Physicist). I've read the inertia article, so the planets are in inertial motion now yes? So did something have to accelerate them initially?
The force responsible for keeping planets in their consistent orbit is gravity. This force is generated by the mass of the planet and the mass of the sun.
Gravity pulls objects towards each other. In the case of planets, the gravitational force between the planet and the sun keeps the planet in its orbit. The planet's motion around the sun is balanced by the gravitational force, resulting in a consistent orbit.
While the orbits of planets may appear to be circular, they are actually elliptical. This is due to the fact that the gravitational force between the planet and the sun is not constant throughout the orbit. As the planet moves closer to the sun, the force of gravity increases, causing the planet to speed up and move into a tighter, more elliptical orbit.
No, the speed at which a planet orbits the sun varies depending on its distance from the sun. The closer a planet is to the sun, the faster it orbits. This is due to the stronger gravitational force at shorter distances.
Yes, a planet's orbit can change over time due to a variety of factors such as the gravitational pull of other planets, asteroids, or comets. These external forces can disrupt the balance of forces that keep a planet in its orbit, causing it to change over time.