Nicolaus Copernicus never married, according to Mental Floss. This should come as no surprise considering that he’d taken a vow of celibacy, and getting released from that vow and being allowed to marry would have been a whole thing. However, it hardly needs stating that it’s eminently possible to have a sexual relationship with someone without the benefit of marriage, and Copernicus may or may not have taken advantage of that loophole.

In his later years, the astronomer lived with a woman named Anna Schilling, City of Torun claims. The site notes, rather dryly, that Copernicus was in his 60s at the time, “an age sufficiently mature for it to be difficult to suspect him of promiscuity.” Further, Schilling was probably just his housekeeper, and indeed, may have been his great-niece. Regardless of the likely innocence of the arrangement, it bothered his superiors to the point that he was more than once asked to fire her. However, the astronomer died before the matter was sorted out, and the question of his lifetime celibacy remains unanswered.