M91

M91 (or NGC 4548 ) is a Spiral galaxy located in the Constellation of the Chevelure of Bérénice.

Discovered

M91 probably was discovered by Charles Messier on March 18th 1781, but the position which it reported in his catalog was erroneous, it was thus redécouverte independently by William Herschel on April 8th 1784. In fact, to determine the position of M91, Messier had based itself on that of M89, by thinking that it was about M58, the M91 object thus formed part of the missing objects of the Messier catalog until this error is included/understood in 1969.

Characteristics

M91 is a barred spiral galaxy of standard SBb, member of a Galaxy cluster called Virgo Cluster. She moves away from the Solar system at the speed of 400 km/sec (since the Virgo Cluster as a whole moves away from the solar system to 1100 km/sec, this means that M91 moves inside the cluster at the speed of 700 km/sec in the direction of the solar system).

External bonds

Messier 91, page of '' SEDS ''

Random links: