M 11
OPEN STAR CLUSTER
Right Ascension:
18h 51m 6s
Best Seen:
7/15-11/1
Declination:
-6º 16' 00"
Magnitude:
6.3
Computer File:
m11
Constellation:
Scutum
Actual
Compared to
Distance
~ 6000 l.y.
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Actual Brightness
--
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Number of stars
~ 2,900
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Diameter
24 l.y.
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Age
~ 220 to 500 million years (most recent estimate 250 million years)
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Integrated Spectral Type
--
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WHAT TO LOOK FOR THROUGH THE TELESCOPE:
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Recommended eyepiece: 40mm or 80 mm.
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Through the telescope the cluster will appear as a group of individual stars.
M 11 INFORMATION:
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This cluster is also called the Wild Duck Cluster, apparently because it resembles a flight of wild ducks when viewed through a telescope.
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Most of the brightest main sequence stars are of spectral type A and F.
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It also has about 500 stars which are brighter than 14th magnitude.
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The average separation of the stars in the cluster is about 1 light year.
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All of the bright stars in this cluster are very luminous giants.
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The total brightness of the cluster is about 10,000 times the brightness of the sun.
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M11 was first discovered by Gottfried Kirch of the Berlin Observatory in 1681, and apparently was first resolved into stars by William Derham in 1733.
Item
Updated
Notes
Coordinates
12-09-2002
OK with SIMBAD and http://www.seds.org/messier/m/m011.html
Magnitude
12-09-2002
OK with SIMBAD and http://www.seds.org/messier/m/m011.html
Distance
12-09-2002
SEDs site (see magnitude) gives 6,000, but an APOD site gives “over 3000 light years" at http://antwrp.gsfc.nasa.gov/apod/ap001022.html
Actual Brightness
Number of Stars 12-09-2002
05-17-2005
previously said “more than 870,” but could only find info at http://www.seds.org/messier/m/m011.html
updated from SEDS
Diameter
12-09-2002
05-19-2005
16 ly difficult to find any info
24 ly number based on parallax calculation by Jason F with SEDS numbers: diameter of 14 arc.min and 6kly dist. Result is 7.36pc.
Age
05-17-2005
from http://www.seds.org/messier/m/m011.html
Integrated Spectral Type
Other Information
12-09-2002
Wild Duck name origin: http://www.astropix.com/HTML/D_SUM_S/M11.HTM
Kirch and Derham info from SEDs site
DIFFICULT to find ANY supporting info for the other items except #3 (SEDS site)