NGC 4550 & NGC 4551 -- Galaxies in Virgo
A Galaxy with Half its Stars Rotating in the Wrong Direction
About a degree of space separates the famous Messier Virgo Galaxies M58 and M89. About
one-halfway between them and slightly off center rests the much dimmer galaxies NGC 4550
and NGC 4551. Although these two galaxies appear close to each other, no interaction
between them has been reported. NGC 4550 is interesting in that approximately half of its
disk stars rotate counterclockwise and the other half rotate clockwise around the galactic core.
This is not at all normal and must be the result of a serious merger or disruption in the galaxy’s
Both galaxies are difficult objects with the 155mm refractor under suburban skies with NGC
4551 noticeable only with patience and additional magnification. No details, outside of shape,
could be seen in either galaxy. The drawing circle was done at 137x, but the galaxies were
teased/drawn out at 232x.