M64

M64 is also known as the Black Eye galaxy, due to a conspicuous dark structure made of dust obscuring the stars behind. M64 was recently shown to have two counterrotating systems of stars and gas in its disk: The inner part of about 3,000 light years radius is rubbing along the inner edge of the outer disk, which rotates opposite and extends up to at least 40,000 light years, at about 300 km/sec. This rubbing process is probably the reason for an observed region of vigorous star formation which is currently under way, and can be observed as the knots imbedded in the peculiar dust lane on one side of the nucleus. It is speculated that this peculiar disk and dust lane may be caused by material from a former companion which has been accreted but has yet to settle into the mean orbital plane of the disk. The dark dust feature was discovered by William Herschel who observed M64 twice in 1785 and 1789, and already compared it to a "Black Eye." The distance of this galaxy is not well known and estimates vary from 12 million to 25 million light-years. No supernovae have been recorded in M64 up to now.