Messier 41

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Messier 41
Messier 041 2MASS.jpg
Credit: 2MASS/NASA
Observation data (J2000 epoch)
Constellation Canis Major
Right ascension 06h 46.0m[1]
Declination −20° 46′[1]
Distance 2,300 ly[2] (710 pc)
Apparent magnitude (V) 4.5[1]
Apparent dimensions (V) 38 arcmin[2]
Physical characteristics
Radius 12.5 ly
Estimated age 190-240 million yrs[citation needed]
Other designations M41,[1] NGC 2287[1]
See also: Open cluster, List of open clusters

Messier 41 (also known as M41 or NGC 2287) is an open cluster in the Canis Major constellation. It was discovered by Giovanni Batista Hodierna before 1654 and was perhaps known to Aristotle about 325 BC.[3] M41 lies about four degrees almost exactly south of Sirius, and forms a triangle with it and Nu2 Canis Majoris—all three can be seen in the same field in binoculars. The cluster itself covers an area around the size of the full moon.[4] It contains about 100 stars including several red giants, the brightest being a spectral type K3 giant of apparent magnitude 6.3 near the cluster's center, and a number of white dwarfs.[5][6][7] The cluster is estimated to be moving away from us at 23.3 km/s.[1] The diameter of the cluster is between 25 and 26 light years. Its age is estimated at between 190 and 240 million years old. M41 is also referred to as NGC 2287.

Walter Scott Houston describes the appearance of the cluster in small telescopes:[8]

Many visual observers speak of seeing curved lines of stars in M41. Although they seem inconspicuous on photographs, the curves stand out strongly in my 10-inch [reflecting telescope], and the bright red star near the center of the cluster is prominent.

See also[edit]

References[edit]

  1. ^ a b c d e f "SIMBAD Astronomical Database". Results for Messier 41. Retrieved 2006-12-21. 
  2. ^ a b "Messier Object 41". SEDS. Retrieved 2009-12-10. 
  3. ^ M41 possibly recorded by Aristotle
  4. ^ Kambic, Bojan (2009). Viewing the Constellations with Binoculars: 250+ Wonderful Sky Objects to See and Explore. New York, New York: Springer. p. 230. ISBN 0387853553. 
  5. ^ Koester, D. Reimers, D. (1981), "Spectroscopic identification of white dwarfs in Galactic Clusters I. NGC2287 and NGC3532", Astronomy & Astrophysics, 99, L8-11
  6. ^ De Laet, Rony (2011). The Casual Sky Observer's Guide: Stargazing with Binoculars and Small Telescopes (in delaet11). New York, New York: Springer. pp. 95–97. ISBN 1461405955. 
  7. ^ Dobbie, P., Day-Jones, A., Williams, K., Casewell, S., Burleigh, M., Lodieu, N., Parker, Q., Baxter, R., (2012), "Further investigation of white dwarfs in the open clusters NGC2287 and NGC3532", Monthly notices of the Royal Astronomical Society, 423, 2815-2828
  8. ^ Houston, Walter Scott (2005). Deep-Sky Wonders. Sky Publishing Corporation. ISBN 1-931559-23-6. 

External links[edit]

Coordinates: Sky map 06h 46.0m 00s, −20° 46′ 00″