Ruprecht 44 | |
---|---|
Observation data (J2000 epoch) | |
Constellation | Puppis |
Right ascension | 07h 58m 54.0s [1] |
Declination | −28° 35′ 00″ [1] |
Distance | 6,600 pc |
Physical characteristics | |
Estimated age | ~106 years |
Other designations | C 0757-284, KPR2004b 176, KPS2012 MWSC 1398 |
Ruprecht 44 is an open cluster in the Milky Way galaxy. It is about 6,600 pc away in the constellation Puppis. [2] Ruprecht 44 is a very young open cluster, only about several million years old. [3]
Star name | LSS number | Effective temperature | Absolute magnitude | Bolometric magnitude | Mass (M☉) | Spectral type | Ref. |
---|---|---|---|---|---|---|---|
WR 10 (HD 65865) | LSS 916 | 63000 | -4.2 | -8.5 | 25 | WN4.5 | [4] |
LSS 891 | 37200 | -4.4 | -8 | 27 | O8III(f) | [4] | |
LSS 898 | 35100 | -4.3 | -7.7 | 24 | Be | [4] | |
LSS 902 | 31600 | -4.7 | -7.9 | 23 | B0V | [4] | |
LSS 920 | 34700 | -3.7 | -7.1 | 21 | O9.5V | [4] | |
LSS 907 | 31600 | -4.3 | -7.4 | 20 | B0V | [4] | |
A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek galaxias (γαλαξίας), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. Galaxies, averaging an estimated 100 million stars, range in size from dwarfs with less than a hundred million stars, to the largest galaxies known – supergiants with one hundred trillion stars, each orbiting its galaxy's center of mass. Most of the mass in a typical galaxy is in the form of dark matter, with only a few percent of that mass visible in the form of stars and nebulae. Supermassive black holes are a common feature at the centres of galaxies.
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