Arefers to one of the largest social units and includes a population of people, usually living within a specified geographic area, connected by common ideas and subject to a particular political authority.

Community

Explanation:

A community is the largest social unit sharing such things as norms, religion, values, customs, or identity. Communities may also share or be situated in a given geographical area or space, for example: country, village, town, or neighbourhood.

Although communities are usually small with regard to personal social connections, "community" in its broad sense could also extend to large group affiliations such as international communities, national communities, and virtual communities.

a. the moon was locked into orbit by the earths gravity as it was passing by and capture hypothesis i think

the density would be a smaller number.