B Is the Earth falling into the sun from gravity?

[BadgerBadger92]

TL;DR 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?

 

[Drakkith]

The Earth is in free fall around the Sun thanks to gravity, but it is not, on average, getting closer to the Sun.

 

[PeterDonis]

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.

 

[Drakkith]

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;

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?

 

[sophiecentaur]

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?

You'd need to consider accretion by both bodies, too.

 

[PeterDonis]

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.

 

[Vanadium 50]

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?

What work have you already done to answer this? (It's okay...we all know the answer)

 

[Vanadium 50]

And, as usual, just another drive-by posting.