M 47
OPEN STAR CLUSTER
Right Ascension:
7h 36m 36s
Best Seen:
2/15-5/1
Declination:
-14º 30' 00"
Magnitude:
5.2
Computer File:
m47
Constellation:
Puppis
Actual
Compared to
Distance
~ 1,600 l.y.
--
Actual Brightness
--
--
Number of stars
~ 50
--
Diameter
12 l.y.
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Age
78 million years
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Integrated Spectral Type
--
--
WHAT TO LOOK FOR THROUGH THE TELESCOPE:
-
Recommended eyepiece: 40mm or 80 mm.
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When people look through the telescope the cluster will appear as a group of individual stars; much like sugar or salt sprinkled on a table top.
M47 INFORMATION:
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This cluster was discovered before 1654 by Giovanni Batista Hodierna. He described it as “a Nebulosa between the two dogs.” However, this wasn’t realized until 1984, when his long forgotten published catalog was rediscovered.
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Charles Messier independently discovered M47 in 1771. However, he made an error when computing its position, so it was a “missing object” until 1934. In that year, Oswald Thomas identified the cluster as Messier’s M47.
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As a consequence of Messier’s error, William Herschel also independently rediscovered the cluster in 1785.
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Under good observing conditions, M47 can be seen with the unaided eye as a dim nebulosity.
Item
Updated
Notes
Coordinates
01-04-03
tweaked a bit
Distance
01-04-03
OK with http://www.seds.org/messier/m/m047.html
Actual Brightness
Number of Stars
01-04-03
OK with http://www.seds.org/messier/m/m047.html
Diameter
01-04-03
OK with http://www.seds.org/messier/m/m047.html
Age
01-04-03
OK with http://www.seds.org/messier/m/m047.html
Integrated Spectral Type
Other Information
01-05-03
lots from http://www.seds.org/messier/m/m047.html