Many galaxies are visible in the field of view of this cosmic vista and three are particular noteworthy. M49, at right in the image above, was the first member of the Virgo Cluster of galaxies to be discovered by Charles Messier in 1771. With a magnitude of 8.3 and located about 50 million light-years away in the constellation of Virgo, M49 is supposed to have a supermassive black hole in its nucleus with an estimated mass 565 million times the mass of the Sun. This galaxy has a large collection of globular clusters, estimated at about 5,900. Barely visible around M49 is a faint extended, interleaved shell system reminiscent of the radial accretion of a satellite companion, discovered only in 2010. NGC4526, at left in the image above, is a lenticular galaxy with a magnitude of 9.6, located in between two relatively bright stars that makes it an easy target to be spotted visually. NGC 4535 is the bright spiral galaxy above NGC 4526. It was discovered in 1785 by William Herschel that described it as an easy object and at 9.8 has a similar magnitude of the latter. Due to the relative brightness and close location to M49, it is surprising how Messier missed these two galaxies, hence the nicknames of "lost galaxies". Apo TEC140 (140/f7.2) - FLI Proline 16803 - L (540m) R (130m) G (130m) B (120m) - Warrumbungle Observatory, Coonabarabran, NSW, Australia
The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy some two and a half million light-years away. But without a telescope, even this immense spiral galaxy - spanning over 200,000 light years - appears as a faint, nebulous cloud in the constellation Andromeda. In contrast, a bright yellow nucleus, dark winding dust lanes, gorgeous blue spiral arms and star clusters are recorded in this telescopic digital image. While even casual skygazers are now inspired by the knowledge that there are many distant galaxies like M31, astronomers seriously debated this fundamental concept less than 90 years ago. Were these "spiral nebulae" simply outlying components of our own Milky Way Galaxy or were they instead "island universes" -- distant systems of stars comparable to the Milky Way itself? This question was central to the famous Shapley-Curtis debate of 1920, which was later resolved by observations of M31 in favor of Andromeda, island universe (text adapted from APOD). TEC 140APO & AP Mach1 - FLI Proline 16803 - Ha (180m) L (150m) R (45m) G (45m) B (45m) - Gambugliano, Vicenza, Italy
Only 11 million light-years away, Centaurus A is the closest active galaxy to planet Earth. Spanning over 60,000 light-years, the peculiar elliptical galaxy, also known as NGC 5128, is featured in this sharp color image. Centaurus A is apparently the result of a collision of two otherwise normal galaxies resulting in a fantastic jumble of star clusters and imposing dark dust lanes. Near the galaxy's center, left over cosmic debris is steadily being consumed by a central black hole with a billion times the mass of the Sun. As in other active galaxies, that process likely generates the radio, X-ray, and gamma-ray energy radiated by Centaurus A (text adapted from APOD). Apo TEC140 (140/f7.2) - FLI Proline 16803 - L (560m) R (60m) G (80m) B (80m) - Warrumbungle Observatory, Coonabarabran, NSW, Australia
