NGC 2509 is an open cluster in the constellation of Puppis. It was discovered on 3 December 1783 by William Herschel.[3] It was described as "bright, pretty rich, slightly compressed" by John Louis Emil Dreyer, the compiler of the New General Catalogue.[3]

NGC 2509
DSS image of NGC 2509
Observation data (J2000 epoch)
Right ascension08h 00m 48s[1]
Declination−19° 03′ 06″[1]
Distance9,500 ly (2,900 pc[1])
Apparent magnitude (V)9.3[2]
Apparent dimensions (V)2.5 ± 0.5
Physical characteristics
Estimated age1,200 Myr[1]
Other designationsNGC 2509, Cr 171, Mel 81, OCl 630[2]
Associations
ConstellationPuppis
See also: Open cluster, List of open clusters

The cluster is about 14 light-years (4.2 parsecs) wide,[1] but the cluster's other parameters remain poorly known. Some studies have estimated a distance of about 9,500 light-years (2,900 parsecs) away from the Solar System,[1] while older estimates put it at only 2980 light-years (912 parsecs) away.[4] Estimates of the cluster's age have also varied significantly, from 1.2 billion years old[1] to 8 billion years old.[4] The latest analysis based on the parallaxes measured by the Gaia spacecraft confirms that it is a relatively distant object, with a distance between 2500 and 3000 parsecs.[5]

References

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  1. ^ a b c d e f g Carraro, G.; Costa, E. (2007). "Photometry of the five marginally studied open clusters Collinder 74, Berkeley 27, Haffner 8, NGC 2509, and VdB-Hagen 4". Astronomy & Astrophysics. 464 (2): 573. arXiv:astro-ph/0611705. Bibcode:2007A&A...464..573C. doi:10.1051/0004-6361:20066350. S2CID 1419651.
  2. ^ a b "NGC 2509". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 9 August 2017.
  3. ^ a b "New General Catalog Objects: NGC 2500 - 2549". cseligman.com. Retrieved 9 August 2017.
  4. ^ a b Sujatha, S.; Babu, G. S. D. (2003). "Study of open cluster NGC 2509". Bulletin of the Astronomical Society of India. 31: 9–18. Bibcode:2003BASI...31....9S.
  5. ^ Cantat-Gaudin, T.; Jordi, C.; Vallenari, A.; et al. (2018). "A Gaia DR2 view of the open cluster population in the Milky Way". Astronomy & Astrophysics. 618: A93. arXiv:1805.08726. Bibcode:2018A&A...618A..93C. doi:10.1051/0004-6361/201833476. S2CID 56245426.