Celestial Objects
Messier 40
Multiple Star Systems
Citation Formats
General Reference
APA Style
BibTeX
Messier 40, also known as Winnecke 4, is an optical double star in the constellation Ursa Major, made up of two stars that appear close together as seen from Earth but are not physically related to one another. It is the fortieth entry in Charles Messier's catalogue of nebulous and cluster-like objects.
Reader Challenges (0 open reader challenges)
No disputes yet. Spotted an error or a better source? Open the first one.
Sign in to dispute this or suggest a correction.
View At A Past Year
The atlas records no dated fact of its own for this entry, so there is no other year to choose.