Messier 47 (M47)

Also Known as: NGC 2422, Collinder 152

Object Type: Open Cluster

Constellation: Puppis

Distance from Earth: 1,600 light years

Apparent Magnitude: 4.2

Coordinates: RA 07H 36.6M 0S DEC -14 deg 30 min 0 sec

Actual Size: 12 light years in diameter

Apparent Dimensions: 30 arc-minutes

Discovered by: The cluster was discovered by the Italian astronomer Giovanni Battista Hodierna before 1654. Hodierna described it as “a Nebulosa between the two dogs.” His discovery, however, did not come to light until the 1980s because his work was largely forgotten for a few centuries.
Charles Messier independently discovered the cluster on February 19, 1771. He described it as a “cluster of stars, little distant from the preceding; the stars are greater; the middle of the cluster was compared with the same star, 2 Navis. The cluster contains no nebulosity.”

Description: Messier 47 (M47) is a bright open star cluster located in the southern constellation Puppis.
M47 is a bright open cluster consisting of 50 stars and with an age of 70 million years.
It is one of the least densely populated open clusters and contains many luminous blue stars and a few older red giants. The cluster is roughly the same apparent size as the full Moon. The cluster is located close to Messier 46, a considerably older and more distant open cluster.
M46 has significantly more stars, but appears much dimmer because it lies at a greater distance from Earth. M46 lies about a degree to the southeast of M47.
The two clusters can be seen in the same field of view in binoculars and small telescopes. Another cluster, NGC 2423, which lies just 0.5 degrees north of M47, is also visible in the same view.
The cluster contains many luminous blue stars and a few older red giants. The brightest stars in M47 have a visual magnitude of 5.7.
The single brightest star in the cluster is of the spectral type B2.
The cluster also contains two K-type orange giants, each about 200 times more luminous than the Sun. M47 is moving away at 9 km/s.

Click Below Image(s) for Full Size:

M47 is visible with the un-aided eye in dark, clear skies.
It appears as a hazy patch. It is easy to find and easily resolved with 10x50 binoculars which reveal the brighter stars.
Larger binoculars and small telescopes show many dimmer stars in M47, while 6-inch telescopes reveal a loose cluster with many bright and faint stars spread across an area 30 arc minutes in diameter.

M47 is best seen from southern and equatorial latitudes during the months of December, January and February

Platesolve

M47 Open Cluster

Imaging Details
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