Winnecke 4
Encyclopedia
Winnecke 4 is a double star
in the constellation Ursa Major
. It was discovered by Charles Messier
in 1764 while he was searching for a nebula that had been reported in the area by Johann Hevelius. Not seeing any nebulae, Messier catalogued this double star instead. It was subsequently rediscovered by Friedrich August Theodor Winnecke
in 1863. Burnham
calls M40 "one of the few real mistakes in the Messier catalog," faulting Messier for including it when all he saw was a double star, not a nebula of any sort.
In 1991 the separation between the components was measured at 51".7, an increase since Messier's time. Data gathered by astronomers Brian Skiff (2001) and Richard L. Nugent (2002) strongly suggest that this is merely an optical double star rather than a physically connected system.
Double star
In observational astronomy, a double star is a pair of stars that appear close to each other in the sky as seen from Earth when viewed through an optical telescope. This can happen either because the pair forms a binary star, i.e...
in the constellation Ursa Major
Ursa Major
Ursa Major , also known as the Great Bear, is a constellation visible throughout the year in most of the northern hemisphere. It can best be seen in April...
. It was discovered by Charles Messier
Charles Messier
Charles Messier was a French astronomer most notable for publishing an astronomical catalogue consisting of deep sky objects such as nebulae and star clusters that came to be known as the 110 "Messier objects"...
in 1764 while he was searching for a nebula that had been reported in the area by Johann Hevelius. Not seeing any nebulae, Messier catalogued this double star instead. It was subsequently rediscovered by Friedrich August Theodor Winnecke
Friedrich August Theodor Winnecke
Friedrich August Theodor Winnecke was a German astronomer.He worked at Pulkovo Observatory from 1858 to 1865, but returned to Germany and served as professor of astronomy at Strasbourg from 1872 to 1881.He discovered or co-discovered a large number of comets, including the periodic comet...
in 1863. Burnham
Robert Burnham, Jr.
Robert Burnham, Jr. was an American astronomer. He is best known for writing the classic three-volume Burnham's Celestial Handbook.-Early work:...
calls M40 "one of the few real mistakes in the Messier catalog," faulting Messier for including it when all he saw was a double star, not a nebula of any sort.
In 1991 the separation between the components was measured at 51".7, an increase since Messier's time. Data gathered by astronomers Brian Skiff (2001) and Richard L. Nugent (2002) strongly suggest that this is merely an optical double star rather than a physically connected system.