| NGC 2509 | |
|---|---|
 DSS image of NGC 2509 | |
| Observation data (J2000 epoch) | |
| Right ascension | 08h 00m 48s [1] |
| Declination | −19° 03′ 06″ [1] |
| Distance | 9,500 ly (2,900 pc [1] ) |
| Apparent magnitude (V) | 9.3 [2] |
| Apparent dimensions (V) | 2.5 ± 0.5′ |
| Physical characteristics | |
| Estimated age | 1,200 Myr [1] |
| Other designations | NGC 2509, Cr 171, Mel 81, OCl 630 [2] |
| Associations | |
| Constellation | Puppis |
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]
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]
