Small dumbbell nebula
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Planetary Nebula Messier 76 / Small Dumbbell Nebula |
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| Image taken with the 81 cm reflecting telescope of the Mount Lemmon Observatory . | |
| AladinLite | |
| Constellation | Perseus |
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Position equinox : J2000.0 |
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| Right ascension | 01h 42m 19.7s |
| declination | + 51 ° 34 ′ 32 ″ |
| Appearance | |
| Apparent brightness (visual) | 10.1 mag |
| Apparent brightness (B-band) | 12.2 mag |
| Angular expansion | 3.12 ′ × 3.12 ′ |
| Central star | |
| designation | HD 10346 |
| Apparent brightness | 16.6 mag |
| Physical data | |
| Redshift | −64 · 10 −6 |
| Radial velocity | −19.1 km / s |
| distance | 3,400 ly |
| history | |
| discovery | Pierre Méchain |
| Date of discovery | September 5, 1780 |
| Catalog names | |
| NGC 650 • PK 130-10.1 • GC 385 • H I 193 • NGC 651 • Messier 76 | |
The small dumbbell nebula (also known as Messier 76 or NGC 650 ) is a planetary nebula in the constellation Perseus with an apparent magnitude of 10.1 mag. The lighter core area, also known as the "cork", measures 1.45 '× 0.7' arc minutes . The slightly weaker outer part is almost twice as large. Because of its shape, the object is called the Butterfly Nebula or the Small Dumbbell Nebula . All around the outside there is a halo , which consists of the gas material that the star had given off long before the explosion in its phase as a red giant . This is just under 4.8 minutes of arc . At the distance of the nebula, this value corresponds to an absolute extent of about 21 light years.
The central star appears as a binary star system . However, based on images taken with the Hubble Space Telescope , it could be shown that the southern component is actually about 20,000 light years behind the nebula. These two stars form what is known as an optical binary star system. Their distance is 1.4 arc seconds .
For a long time this object was considered to be a double nebula, which led to it being given two NGC numbers. At the end of the 19th century, spectroscopic analyzes finally demonstrated that it was a planetary nebula.
discovery
The planetary nebula NGC 650 was discovered on September 5, 1780 by the French astronomer Pierre Méchain .
