Doppler Red Shift

[sciconoclast]

My understanding of the orthodox view of cosmic red shift is that it is the result of both Doppler effect and the expansion of space. My question concerns the doppler portion. It seems that if the red shift of a distant object is measured while the earth is moving towards that object and then again six months later when moving away from the same object the red shift should be different. First would the orbit and rotation of the earth be great enough to produce a measurable Doppler shift? Second do you readily know if this comparison has ever been made and if so what the results where. If it hasn't been done there is likely already enough red shift measurements to distant objects that are in the earth orbit plane to make the comparison. How could I access this data? You have probably already guessed that I have some theoretical doubts about what would be the expected results.

 

[MeteorWayne]

Yes that has been done. I'm don't have the numbers at hand, but that is regularly done as a matter of course. The position of the earth in it's orbit, and the resultant motion is required in order to detect extrasolar planets using the doppler method (about 90% of all detections so far).

It is also figured into the far larger redshifts of distant galaxies.

 

[Saiph]

Yep, the earths motion makes a doppler shift in the data, and it's been factored into various calculations for a long time. They also consider the suns proper motion in many cases, and the fact that the earth doesn't orbit the exact center of the solar system. In sensitive measurements the earths rotation, and the wobble due to the moon are also considered.