hd-218641

Its story

It isn't one star, it's two. This A-class white in Aquarius forms a binary system, two bodies bound by mutual gravity, dancing around their common centre of mass. Its light reaches us from one hundred and fifty-five light-years away, having left the star around 1870, when the Suez Canal was being inaugurated at Port Said. The naked eye sees a single dot; only the telescope or the spectrum reveals the pair.