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houlahound
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As I understand it a coordinate origin is just chosen for convenience. So how can we state the Earth revolves around the sun when you could make coordinate origin at any point in the universe??
You CAN choose your coordinate system anywhere you like, and in that coordinate system, the Earth will revolve around the sun. Also, in that coordinate system, the Sun revolves around the center of the Milky Way. These things represent physical reality.houlahound said:As I understand it a coordinate origin is just chosen for convenience. So how can we state the Earth revolves around the sun when you could make coordinate origin at any point in the universe??
houlahound said:But I am free to choose where I make the coordinate origin and have everything move relative to that point...I think.
houlahound said:So then why we claim one way or the other if both are equally valid, precisely my original question??
Changing the coordinate system does not change the actual motion - it is just a different way to calculate the same thing. If you choose a coordinate system that doesn't fit well with the actual motion (ie, with the sun at the center), it makes the calculations harder.houlahound said:So then why we claim one way or the other if both are equally valid, precisely my original question??
You mean they both "orbited" their combined center of mass? And the combined center of mass was closer to the larger one? Because they should both "orbit" at the same rate, since its the system that's rotating.houlahound said:I just threw a heavy and light ball tied by a rope, one does orbit more than the other. Got nearly three ball "years" before my solar system crashed.
Aaaah yep, that exactly what I meant :-)BobG said:You mean they both "orbited" their combined center of mass? And the combined center of mass was closer to the larger one? Because they should both "orbit" at the same rate, since its the system that's rotating.
Quite right. In fact, the Sun orbits the Earth, as the Ancients figured out a long, long time ago. Shame on Copernicus and Galileo for opposing Church doctrine!houlahound said:As I understand it a coordinate origin is just chosen for convenience. So how can we state the Earth revolves around the sun when you could make coordinate origin at any point in the universe??
The position of our origin does not affect our orbit around the sun. Our orbit is determined by the gravitational pull of the sun, which remains constant regardless of the position of our origin.
Yes, we can change our origin and still maintain our orbit around the sun. As long as the distance between our origin and the sun remains the same, our orbit will not be affected.
Yes, the sun is always at the center of our orbit. This is due to the strong gravitational pull of the sun, which keeps all the planets in our solar system in orbit around it.
The position of our origin in relation to the sun can be determined using a coordinate system. The most commonly used coordinate system in astronomy is the heliocentric coordinate system, which places the sun at the center of the system and measures the position of other objects in the solar system in relation to it.
Yes, our orbit around the sun can be affected by other objects in the solar system. For example, the gravitational pull of other planets can cause slight variations in the shape and speed of our orbit. However, the overall stability of our orbit is maintained by the sun's strong gravitational pull.