Article · Wikipedia archive · Last revised Jun 27, 2026

Messier 41

Messier 41 (also known as M41 or NGC 2287) is an open cluster in the constellation Canis Major. Located approximately four degrees south of Sirius, it forms a roughly equilateral triangle with Sirius and Nu2 Canis Majoris, visible together in binoculars. The cluster spans an area comparable to the size of the full moon and contains about 100 stars, including several red giants and white dwarfs.

Last revised
Jun 27, 2026
Read time
≈ 2 min
Length
552 w
Citations
19
Source
Wikipedia ↗
Messier 41
Open cluster Messier 41 in Canis Major
Observation data (J2000 epoch)
Right ascension06h 46.0m 1
Declination−20° 46′1
Distance2,360 ly2 (725 pc)
Apparent magnitude (V)4.51
Apparent dimensions (V)38 arcmin3
Physical characteristics
Radius12.5 ly
Estimated age200 million yrs2
Other designationsM41,1 NGC 22871
Associations
ConstellationCanis Major

Messier 41 (also known as M41 or NGC 2287) is an open cluster in the constellation Canis Major. Located approximately four degrees south of Sirius, it forms a roughly equilateral triangle with Sirius and Nu2 Canis Majoris, visible together in binoculars.4 The cluster spans an area comparable to the size of the full moon and contains about 100 stars, including several red giants and white dwarfs.45

Discovery and history

Discovered by Giovanni Batista Hodierna before 1654, M41 may have been observed by Aristotle as early as 325 BC.6 It is sometimes called the Little Beehive Cluster due to its resemblance to the Beehive Cluster (M44).7

Characteristics

The brightest star in M41 is a red giant of spectral type K3 with an apparent magnitude of 6.3 near the cluster's center.8 The cluster has a diameter of 25–26 light-years (7.7–8.0 pc) and is receding from Earth at 23.3 km/s.1 Estimates suggest an age of 190 million years, with a predicted lifespan of 500 million years before disintegration.9

Observation

Walter Scott Houston noted its appearance in small telescopes:10

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.

The prominent red-orange central star, HIP 32406, is a K2-type giant of magnitude 6.9, located ~1,500 light-years away.11

  • Center 2MASS/NASA
    Center 2MASS/NASA
  • M41 in an 8" telescope
    M41 in an 8" telescope
  • Sirius and M41 (lower right), M50 (upper left), and NGC 2360 (lower left)
    Sirius and M41 (lower right), M50 (upper left), and NGC 2360 (lower left)
  • M41 finder chart
    M41 finder chart
  • Open cluster M41 taken from a 12-inch Dobson telescope in Viña del Mar
    Open cluster M41 taken from a 12-inch Dobson telescope in Viña del Mar
  • Open cluster Messier 41 in Canis Major
    Open cluster Messier 41 in Canis Major
See also

See also

References

References

2


  1. "M 41". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2006-12-21.
  2. Harris, G. (October 1993). "NGC 2287 - an important intermediate-age open cluster". The Astronomical Journal. 106 (4): 1533–1546. doi:10.1086/116748. ISSN 0004-6256.
  3. "Messier Object 41". SEDS. Retrieved 2024-07-23.
  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 978-0-387-85355-0.
  5. Koester, D. Reimers, D. (1981), "Spectroscopic identification of white dwarfs in Galactic Clusters I. NGC2287 and NGC3532", Astronomy & Astrophysics, 99, L8-11
  6. M41 possibly recorded by Aristotle
  7. The Dog Star and the Little Beehive Cluster
  8. De Laet, Rony (2011). The Casual Sky Observer's Guide: Stargazing with Binoculars and Small Telescopes. New York, New York: Springer. pp. 95–97. ISBN 978-1-4614-0595-5.
  9. Stoyan, Ronald (2008). Atlas of the Messier Objects: Highlights of the Deep Sky. Cambridge University Press. p. 171. ISBN 9780521895545.
  10. Houston, Walter Scott (2005). Deep-Sky Wonders. Sky Publishing Corporation. ISBN 978-1-931559-23-2.
  11. 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


External links