NGC 2439

NGC 2439
NGC 2439 (taken from Stellarium)
Observation data (J2000 epoch)
Right ascension07h 40m 45.0s[1]
Declination−31° 41′ 36″[1]
Distance3.855 kpc (12.57 kly)[2]
Apparent magnitude (V)6.9[3]
Apparent dimensions (V)10″[4]
Physical characteristics
Radius82 ± 23 ly (tidal)
Other designationsCr 158, C 0738-315[3]
Associations
ConstellationPuppis
See also: Open cluster, List of open clusters

NGC 2439 is a sparse[5] open cluster of stars in the constellation Puppis. It has an apparent visual magnitude of 6.9, an angular size of 10 arcminutes, and is visible using a small telescope.[4] This is a young cluster with age estimates in the range of 20–300 million years.[6][7] It has a tidal radius of approximately 82 light years.[2] No chemically peculiar stars have been found.[6]

Distance estimates to this cluster vary widely.[5] Piskunov and associates (2008) gave an estimate of 3,855 kpc.[2] A value in the range 3–4 kpc means the cluster lies well below the Galactic Plane. It is positioned in a hole in the Milky Way's gas and dust, with the reduced absorption resulting in a lower than expected extinction of 1.27 in visual magnitude. This result raises the question of whether this cluster actually exists.[5] It is positioned along the same line of sight as two groups of B-type supergiant stars. The nearer group is located at a distance of 1.03 kpc, while the second group is at 3.2 kpc.[8]

  1. ^ a b Cite error: The named reference Wu2009 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference aaa477_1_165 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference bakich2010 was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference Kaltcheva2001 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Paunzen2002 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference aaa389 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference mnras312_4_753 was invoked but never defined (see the help page).