Perplexing Pairs of Orbs

Sometimes orbs seems to appear in pairs, with only two orbs appearing in the photo, right next to each other.  As in this photo of a New York tower (from October 19, 2015), taken on a dry night with very good air:

Another example is below, from October 23, 2015 (we see Grand Central Terminal).

We can only speculate as to whether some paranormal "buddy system" is at work here.