Physical properties of objects that orbit each other in the universe

[judi6070]

A question from my asronomy class....

Given that we are able to measure positions, velocities and timescales of objects in our universe, what sort of physical properties can we determine for objects that orbit each other in the universe?

I have tried reading through my textbook for ideas and have come up with nothing... any ideas would be greatly appreciated!!

Thanks!

[tony873004]

We can measure mass. The more massive, the quicker they orbit.

[Nereid]

Depending on how the orbits are oriented, wrt us here on Earth, lots of other physical properties become amenable to measurement (albeit, with caveats). For example: radius (of each object), luminosity (ditto), temperature (ditto), limb darkening (ditto), composition of any extended atmosphere, ...