NGC 2438

NGC 2438
Nebula

NGC 2438 and the Calabash Nebula
Observation data: J2000.0 epoch
Right ascension 07h 41.8m
Declination -14° 44′
Distance 2,900 ly ly
Apparent magnitude (V) +10.8
Apparent dimensions (V) 1.1 arcmins
Constellation Puppis
Physical characteristics
Radius - ly
Absolute magnitude (V) -
Notable features Superimposed
on Messier 46
Designations H IV.39, FC 87, PK 231+4.2

NGC 2438 is a planetary nebula about 3,000 light years away in the constellation Puppis.[1] It was discovered by William Herschel on March 19, 1786.[2] NGC 2438 appears to lie within the cluster M46, but it is most likely unrelated since it does not share the cluster's radial velocity.[3][4] The case is yet another example of a superposed pair, joining the famed case of NGC 2818.[3][5]

Long exposures have shown that this planetary nebula has an extended halo,[6] while the more easily visible portion probably dates to the death of the red giant in its center.[2]

Central star

The central star of this planetary nebula is a 17.7-magnitude white dwarf,[2] with surface temperature of about 75,000 K (74,700 °C).[7] It is one of the hottest stars known.

See also

References

  1. ↑ Nemiroff, R.; Bonnell, J., eds. (2011-04-07). "Planetary Nebula NGC 2438". Astronomy Picture of the Day. NASA. Retrieved 2011-04-08.
  2. 1 2 3 "NGC Objects: NGC 2400 - 2449". Retrieved 2011-04-08.
  3. 1 2 Majaess D. J., Turner D., Lane D. (2007). In Search of Possible Associations between Planetary Nebulae and Open Clusters, PASP, 119, 1349
  4. ↑ Kiss, L. L., Szabó, Gy. M., Balog, Z., Parker, Q. A., Frew, D. J. (2008). AAOmega radial velocities rule out current membership of the planetary nebula NGC 2438 in the open cluster M46, MNRAS
  5. ↑ Mermilliod, J.-C., Clariá, J. J., Andersen, J., Piatti, A. E., Mayor, M. (2001). Red giants in open clusters. IX. NGC 2324, 2818, 3960 and 6259, A&A
  6. ↑ "NGC 2438". SEDS. Retrieved 2011-04-08.
  7. ↑ "Planetary Nebula NGC 2438 in Puppis". Retrieved 2011-04-08.

Coordinates: 07h 41m 50.6s, −14° 44′ 05″

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