Astronomy:NGC 1846
| NGC 1846 | |
|---|---|
| File:NGC 1846 Hs-2011-35-b-full tif.tif Picture from the Hubble Space Telescope | |
| Observation data (J2000 epoch) | |
| Constellation | Dorado |
| Right ascension | 05h 07m 34.900s[1] |
| Declination | −67° 27′ 32.45″[1] |
| Distance | 160,000 ly (50000 pc) |
| Apparent magnitude (V) | 10.68[2] |
| Apparent dimensions (V) | 3.8′[1] |
| Physical characteristics | |
| Mass | 5.7×104[2] M☉ |
| Estimated age | 1.70±0.05 Gyr[2] |
NGC 1846 is a globular cluster containing hundreds of thousands of stars in the outer halo of the Large Magellanic Cloud.[3] It was discovered on November 6, 1826, by James Dunlop and is included in the New General Catalogue. At an aperture of 50 arcseconds, its apparent V-band magnitude is 10.68, but at this wavelength, it has 0.07 magnitudes of interstellar extinction.[2]
NGC 1846 is about 1.7 billion years old. Its estimated mass is 5.7×104 M☉, and its total luminosity is 1.68×105 L☉, leading to a mass-to-luminosity ratio of 0.34 M☉/L☉.[2] All else equal, older star clusters have higher mass-to-luminosity ratios; that is, they have lower luminosities for the same mass.[2]
In an image taken by the Hubble Space Telescope in 2006 (see picture), astronomers spotted a green planetary nebula towards the bottom of the image. It is uncertain whether NGC 1846 contains this planetary nebula or if it just happened to be on the same line of sight; however, measurements of the motion of the cluster's stars along with the nebula's central star lead to the conclusion that it is a member of the cluster.[3]
References
- ↑ 1.0 1.1 1.2 "NGC 1846". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=NGC+1846.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Song, Ying-Yi; Mateo, Mario; Bailey, John I.; Walker, Matthew G.; Roederer, Ian U.; Olszewski, Edward W.; Reiter, Megan; Kremin, Anthony (2021). "Dynamical masses and mass-to-light ratios of resolved massive star clusters – II. Results for 26 star clusters in the Magellanic Clouds". Monthly Notices of the Royal Astronomical Society 504 (3): 4160–4191. doi:10.1093/mnras/stab1065.
- ↑ 3.0 3.1 "NASA - NASA's Hubble Finds Stellar Life and Death in a Globular Cluster" (in en). https://www.nasa.gov/mission_pages/hubble/science/life-death.html.
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