Messier 41
The open star cluster Messier 41 2MASS catalog |
|
AladinLite | |
Constellation | Big dog |
Position equinox : J2000.0 |
|
---|---|
Right ascension | 06 h 45 m 59.9 s |
declination | −20 ° 45 ′ 15 ″ |
Appearance
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|
classification | I, 3, r (Trumpler), e (Shapley) |
Brightness (visual) | 4.5 mag |
Brightness (B-band) | 4.89 likes |
Angular expansion | 38 ' |
Number of stars | 100 |
Brightest star | 6.9 likes |
Physical data
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|
Redshift | (+78 ± 6) · 10 −6 |
Radial velocity | (+23.3 ± 1.9) km / s |
distance | 2300 ly (700 pc ) |
diameter | 25 ly |
Age | 190 million years |
history | |
Catalog names | |
M 41 • NGC 2287 • C 0644-206 • OCl 597 • Mel 52 • Cr 118 • Lund 256 • ESO 557-SC14 • |
Messier 41 (also known as NGC 2287 ) is a 4.5 mag bright open star cluster with an angular extent of 38 'in the constellation of the Great Dog . For us it is about 4 ° below Sirius (brightest fixed star in the sky).
Messier 41 (M 41) is one of the brightest of the more distant star clusters in the winter sky and was therefore described in detail as early as 1654 despite its southern declination (−20.7 °). It is possible that Aristotle already knew him around 325 BC. Chr.
The 100 or so stars are about 2300 light years away and spread over ~ 25 light years. The brightest among them (6.9 mag) is a red giant with 700 times solar luminosity . The heliocentric radial relative speed of the cluster is about +23 km / s. It is around 200 million years old.
Stars
designation |
apparent brightness |
Spectral class |
Distance (Lj) |
---|---|---|---|
HD 49126 | 7.26 | B8 III | 2600 |
HD 49068 | 7.43 | K1.5 III | 2450 |
HD 49212 | 7.79 | K0 + II-III | 2550 |
HD 49105 | 7.80 | K0 IIIa | 2470 |