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BadgerBadger92
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- Is the earth getting closer to the sun from gravity? Will we ever collide into the sun?
Is the Earth getting closer to the sun from gravity?
Theoretically, according to GR, any planet orbting a star should emit gravitational waves that will, after enough time has passed, cause its orbit to decay. However, for the Earth orbiting the Sun, this effect is many, many, many orders of magnitude too small to matter; lots of other things will happen (like the Sun turning into a red giant and probably becoming large enough to engulf the Earth) on time scales many, many, many orders of magnitude shorter than any orbital changes due to gravitational wave emission would even be detectable by our most sensitive instruments, let alone get large enough to bring the Earth significantly closer to the Sun.BadgerBadger92 said:Is the Earth getting closer to the sun from gravity?
I wonder if the Sun's loss of mass via solar wind and radiation beats the effect of gravitational waves on Earth's orbit. Any idea?PeterDonis said:Theoretically, according to GR, any planet orbting a star should emit gravitational waves that will, after enough time has passed, cause its orbit to decay. However, for the Earth orbiting the Sun, this effect is many, many, many orders of magnitude too small to matter;
You'd need to consider accretion by both bodies, too.Drakkith said:I wonder if the Sun's loss of mass via solar wind and radiation beats the effect of gravitational waves on Earth's orbit. Any idea?
I haven't done the calculation, but I would expect it to beat GW emission by many orders of magnitude. The GW emission rate for the Earth-Sun system as calculated by GR is really, really, really tiny.Drakkith said:I wonder if the Sun's loss of mass via solar wind and radiation beats the effect of gravitational waves on Earth's orbit. Any idea?
What work have you already done to answer this? (It's okay...we all know the answer)BadgerBadger92 said:Summary:: Is the Earth getting closer to the sun from gravity? Will we ever collide into the sun?
Is the Earth getting closer to the sun from gravity?
The Earth stays in orbit around the sun due to the balance between its forward motion and the pull of gravity from the sun. This results in a circular or elliptical path around the sun.
No, the Earth is not getting closer to the sun over time. In fact, the Earth's orbit is very stable and has remained relatively constant for millions of years.
No, the Earth will not fall into the sun. The sun's gravity is strong, but the Earth's orbital speed is fast enough to keep it in orbit and prevent it from falling into the sun.
Yes, there are certain factors that could potentially change the Earth's orbit and cause it to fall into the sun. For example, a significant disturbance from a large asteroid or comet could alter the Earth's trajectory.
The Earth will continue to orbit the sun for billions of years. As long as the sun remains stable and the Earth's orbit remains relatively constant, the Earth will continue to orbit the sun for a very long time.