Observed Redshift Variation Over TIme

[bitznbitez]

Recently we got to watch G2 as its orbit took it around the black hole at the center of the galaxy. This showed a visual change in direction along with a corresponding redshift to blue shift change on a relatively short timeline. It was really a great event.

Binary stars exhibit the same behavior but where are specific instances of this documented ? I have been unable to locate a catalog binary stars and their orbital periods. I'm sure it exists but all my googles dredge up are generic explanations devoid of any specific named pairs.

Are there any other objects besides G1/2 at galactic center, and binary stars, that we have been able to a change in direction and change in redshift ?

 

[bitznbitez]

http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/wds/orb6

So I found a catalog of optical binaries. But I'm still hunting specific documenation regarding observed red shift variation in these [ Or non optical binaries as well ] over time.

 

[Chronos]

Getting a measurable change in redshift of an orbiting body is directionally dependent - the perpendicularity of the orbital plane to our line of sight being a relevant factor. We can, however, measure the direction of rotation and rotatational velocity of fairly distant galaxies rather easily using doppler shifts. See http://astro.berkeley.edu/~mwhite/darkmatter/rotcurve.html for discussion.

 

[bitznbitez]

Yes you are correct it is directionally dependent and that is what I was hoping to find. With G2 that's what we witnessed a directional change and a corresponding redshift change. I'm sure studies of orbital pairs have been done I just can't find them.

I'll keep looking and thanks for the link.