Messier 66 (M66)

Also Known as: NGC 3627

Object Type: Spiral Galaxy

Constellation: Leo

Distance from Earth: 36 million light years

Apparent Magnitude: 8.9

Coordinates: RA 11H 20M 15S DEC 12 deg 59 min 30 sec

Actual Size: 95,000 light years in diameter

Apparent Dimensions: 9.1 arc-minutes x 4.2 arc-minutes

Discovered by: Messier 66 is one of Charles Messier’s original discoveries.
The comet hunter found it together with its neighbor M65 on March 1, 1780 and added both objects to his catalogue.
The third member of the M66 Group, NGC 3628, was not discovered until April 8, 1784, when William Herschel found it with his telescope, which was considerably larger than the one Messier used.
Messier described M66 as a “nebula discovered in Leo,” adding that “its light is very faint & it is very close to the preceding [Messier 65]: They both appear in the same field in the refractor. The comet of 1773 & 1774 has passed between these two nebulae on November 1 to 2, 1773. Messier didn’t see them at that time, no doubt, because of the light of the comet.”

Description: M66 is the easternmost of the two Messier galaxies in the group.
It lies only 0.33 degrees to the southeast of M65, which is located about 3 degrees to the south-southeast of Theta Leonis.
M66 is the largest and brightest member of the Leo Triplet of galaxies, also known as the M66 Group.
It is an intermediate spiral galaxy containing 200 billion stars. It can be seen in the same field as M65 and NGC 3628, the other members of the Leo Triplet.
M66 is notable for its outstanding dark dust lanes and bright starburst regions along the spiral arms.
The galaxy is moving away at 727 km/s.
Gravitational interaction with the nearby galaxies Messier 65 and NGC 3628 has significantly affected M66.
The galaxy’s past encounter with NGC 3628 has resulted in an extremely high central mass concentration, asymmetrical spiral arms and a clump of H I material – an interstellar cloud composed of neutral atomic hydrogen (H I) – removed from one of the galaxy’s spiral arms. As a result, the galaxy appears to have a conspicuous and unusual structure of spiral arms and dust lanes.
The distorted, hooked spiral arms appear displaced above the plane of the galaxy’s disk. For this reason, Halton Arp included M66 in his Atlas of Peculiar Galaxies as Arp 16.
The encounter with NGC 3628, which occurred roughly a billion years ago, affected both galaxies, displacing M66’s bulge slightly from the center and ripping out a 300,000 light-year tidal stream of stars from NGC 3628.

Click Below Image(s) for Full Size:

M66 is visible even with a small binocular which will reveal a small fuzzy patch. Small telescopes show the oval shape of the galaxy and the bright core. Medium sized telescopes reveal the bright core more clearly and 10 inch scope will show hints of the spiral arms.

The best time to observe M66 is March-May.

Platesolve

M66 Spiral Galaxy

Imaging Details
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