Messier 65, Messier 66 & NGC 3628
Galaxies, Leo
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Messier 65 (also known as NGC 3623) is an intermediate spiral galaxy about 35 million light-years away in the constellation Leo, within its highly equatorial southern half. It was discovered by Charles Messier in 1780. With M66 and NGC 3628, it forms the Leo Triplet, a small close group of galaxies.
Messier 66 or M66, also known as NGC 3627, is an intermediate spiral galaxy in the southern, equatorial half of Leo. It was discovered by French astronomer Charles Messier on March 1, 1780, who described it as “very long and very faint”. This galaxy is a member of a small group of galaxies that includes M65 and NGC 3628, known as the Leo Triplet, or the M66 Group. M65 and M66 make a popular pair for observers, being separated by only 20′.
M66 has a morphological classification of SABb, indicating a spiral shape with a weak bar feature and loosely wound arms. The isophotal axis ratio is 0.32, indicating that it is being viewed at an angle. M66 is receding from us with a heliocentric radial velocity of 696.3±12.7 km/s.[3] It lies 31 million light-years away and is about 95 thousand light-years across with striking dust lanes and bright star clusters along sweeping spiral arms. As of 2018, five supernovae have been observed in M66: SN 2016cok, 2009hd, 1997bs, 1989B, and 1973R. The one detected in 2016, SN 2016cok was discovered by the All-Sky Survey Automated Survey for Supernovae, and it has been categorized as a Type IIp supernova.
Gravitational interaction from its past encounter with neighboring NGC 3628 has resulted in an extremely high central mass concentration; a high molecular to atomic mass ratio; and a resolved non-rotating clump of H I material apparently removed from one of the spiral arms. The latter feature shows up visually as an extremely prominent and unusual spiral arm and dust lane structures as originally noted in the Atlas of Peculiar Galaxies.
NGC 3628, also known as the Hamburger Galaxy or Sarah’s Galaxy, is an unbarred spiral galaxy about 35 million light-years away in the constellation Leo. It was discovered by William Herschel in 1784. It has an approximately 300,000 light-years long tidal tail. Its most conspicuous feature is the broad and obscuring band of dust located along the outer edge of its spiral arms, effectively transecting the galaxy to the view from Earth.
Due to the presence of an x-shaped bulge, visible in multiple wavelengths, it has been argued that NGC 3628 is instead a barred spiral galaxy with the bar seen end-on. Simulations have shown that bars often form in disk galaxies during interactions and mergers, and NGC 3628 is known to be interacting with its two large neighbors.
Telescope: Astro Physics 155EDF f7
Mount: Astro Physics 1200GTO
Camera: SBIG STL-11000M
Guider: SBIG STL-Remote OAG
L: 25×10 mins = 250 mins, R: 14×10 mins = 140 mins, G: 12×10 mins = 120 mins, B: 12×10 mins = 120 mins
Total Imaging Time: 10h 30m
Data Imaged remotely over 4 nights during March 2008.
Data acquisition & Processing by David Churchill.
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