The shape of this orbit isn't consistent; it varies over time, over a period of about a thousand years.

轨道的形状并不是始终如一的；它会随时间变化，变化周期为一百年左右。

youdao

And out of this information you get the radius, the velocity and the period, assuming that you are on Earth in the plane of the orbit of the stars.

除了这个，还能得到半径的大小，速度以及周期，假设你在地球上，和这些恒星环绕的，轨道同处一个平面。

youdao

So, in principle, you can determine for each one of those stars the velocity in orbit, the radius of their orbit and, of course, the period of the binary system.

所以从原则上来说，你们可以决定任何,恒星在轨道中的速度，轨道的半径以及，当然，二元体系的周期。

youdao

Long-period comets,however, may take several hundred years to orbit the sun.

VOA: special.2011.02.09

The asteroid orbits the Sun in 368 days - a period similar to Earth's year - but it does not orbit in the same plane as the Earth.

BBC: Asteroid 2012 DA14 in record-breaking Earth pass