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M11

Messier 11
Wild Duck
NGC 6705
Open Star Cluster
Right Ascension 18h 51m 6s Best Seen 7/15-11/1
Declination -6° 16' 00" Magnitude 6.3
Constellation Scutum

Actual		 Compared
to Sun
Distance ~6,000 ly --
Diameter 24 ly --
Number of Stars ~ 2,900 1
Actual Brightness -- --
Age ~ 220 to 500 million years
(most recent estimate 250 million years)		 5 billion
Integrated Spectral Type -- G2 V
Density (gram/cubic cm) -- --

What To Look For Through The Telescope

  1. Recommended eyepiece: 40mm or 80mm.

  2. Through the telescope the cluster will appear as a group of individual stars.

M11 Information:

  1. This cluster is also called the Wild Duck Cluster, apparently because it resembles a flight of wild ducks when viewed through a telescope. It is also known as the Salt and Pepper Cluster and NGC 6705. It’s common name comes from Admiral Smyth, who noted in the 1800s that its fan-shaped appearance resembles a “flight of wild ducks”.

  2. Most of the brightest main sequence stars are of spectral type A and F.

  3. It also has about 500 stars which are brighter than 14th magnitude.

  4. Open clusters likely formed from the same cloud of gas & dust

  5. The average separation of the stars in the cluster is about 1 light year.

  6. All of the bright stars in this cluster are very luminous giants.

  7. The total brightness of the cluster is about 10,000 times the brightness of the sun.

  8. 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. Charles Messier included it into his catalog in 1764.

  9. This cluster is visible in binoculars or a small telescope.
Home > Star Clusters > Open > M11 > Reference top
References
Item Updated Notes
Coordinates 2002-12-09 OK with SIMBAD and http://www.seds.org/messier/m/m011.html
Magnitude 2002-12-09 OK with SIMBAD and http://www.seds.org/messier/m/m011.html
Distance 2002-12-09 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 2005-05-17 previously said “more than 870,” but could only find info at http://www.seds.org/messier/m/m011.html updated from SEDS
Diameter 2005-05-19 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 2005-05-17 from http://www.seds.org/messier/m/m011.html
Integrated Spectral Type --
Other Information 2002-12-09 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)