They complete one orbit about their common centre of mass every 260 years.

But reason it out for yourself and see if we arrive at any common center.

The two orbit a common center of mass every 3.42 days.

About once a month, a circle around this common center is completed, he said.

As a result, the two bodies orbit around the common center of mass which lies in the space between them.

The black hole and the star orbit their common center of mass.

Three ships, locked together, tried to turn round their common center of mass.

The common center was completed October 4, 1896, and put into use nine days later.

Their might was pouring into a common center and going no farther.

They orbit each other about a common centre of mass, a two body problem.