https://github.com/davepinch/pinchy.cc/blob/master/content/topics/astronomy/catalogs/messier/messier-90/messier-90.md
And, in the first place, I observed, that the great certitude which by common consent is accorded to these demonstrations, is founded solely upon this, that they are clearly conceived in accordance with the rules I have already laid down.
Messier 90 (Wikipedia) Messier 90 (also known as M90 and NGC 4569) is an intermediate spiral galaxy exhibiting a weak inner ring structure about 60 million light-years away in the constellation Virgo. It was discovered by Charles Messier in 1781.