Little Dumbbell Nebula
Encyclopedia
The Little Dumbbell Nebula, also known as Messier 76, NGC 650/651, the Barbell Nebula, or the Cork Nebula, is a planetary nebula
Planetary nebula
A planetary nebula is an emission nebula consisting of an expanding glowing shell of ionized gas ejected during the asymptotic giant branch phase of certain types of stars late in their life...

 in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....

 Perseus
Perseus (constellation)
Perseus is a constellation in the northern sky, named after the Greek hero Perseus. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations defined by the International Astronomical Union...

. It was discovered by Pierre Méchain
Pierre Méchain
Pierre François André Méchain was a French astronomer and surveyor who, with Charles Messier, was a major contributor to the early study of deep sky objects and comets.-Life:...

 in 1780 and included in Charles Messier
Charles Messier
Charles Messier was a French astronomer most notable for publishing an astronomical catalogue consisting of deep sky objects such as nebulae and star clusters that came to be known as the 110 "Messier objects"...

's catalog of comet
Comet
A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...

-like objects as number 76. It was first recognised as a planetary nebula in 1918 by the astronomer
Astronomer
An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using...

 Heber Doust Curtis
Heber Doust Curtis
Heber Doust Curtis was an American astronomer.He studied at the University of Michigan and at the University of Virginia, where he got a degree in astronomy....

. However, there is some contention to this claim, as Isaac Roberts in 1891 did suggest that M76 might be similar to the Ring Nebula (M57), being instead as seen from the side view. The structure is now classed as a bipolar planetary nebula (BPNe).

Distance to M76 is currently estimated as 780 parsec
Parsec
The parsec is a unit of length used in astronomy. It is about 3.26 light-years, or just under 31 trillion kilometres ....

s or 2,500 light years
, making the average dimensions about 0.378 pc. (1.23 ly.) across.

The total nebula shines at the apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...

 of +10.1 with its central star
Central Star
Central Star consists of four residential skyscrapers under construction in Busan, South Korea. The tallest landmark tower measures tall and has 58 floors. Ground was broken by POSCO E&C in 2007 and is completing in 2011....

 or planetary nebula nucleus (PNN) at +15.9v (16.1B) magnitude. The UV-light from the PNN is expanding outer layers that form the present nebula, and has the surface temperature of about 88,400 K
Kelvin
The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all...

. The whole planetary nebula is approaching us at −19.1 km.s−1.

The Little Dumbbell Nebula derives its common name from its resemblance to the Dumbbell Nebula
Dumbbell Nebula
The Dumbbell Nebula is a planetary nebula in the constellation Vulpecula, at a distance of about 1,360 light years....

 (M27) in Vulpecula
Vulpecula
Vulpecula is a faint constellation in the northern sky. Its name is Latin for "little fox", although it is commonly known simply as the fox. It was identified in the seventeenth century, and is located in the middle of the Summer Triangle .-Stars:There are no stars brighter than 4th magnitude in...

. It was originally thought to consist of two separate emission nebulae and was thus given two catalog numbers in the NGC
New General Catalogue
The New General Catalogue of Nebulae and Clusters of Stars is a well-known catalogue of deep sky objects in astronomy. It contains 7,840 objects, known as the NGC objects...

 650 and 651. Some consider this object the faintest and hardest to see objects in Messier's list.

See also

  • Messier object
    Messier object
    The Messier objects are a set of astronomical objects first listed by French astronomer Charles Messier in 1771. The original motivation of the catalogue was that Messier was a comet hunter, and was frustrated by objects which resembled but were not comets...

  • List of Messier objects
  • New General Catalogue
    New General Catalogue
    The New General Catalogue of Nebulae and Clusters of Stars is a well-known catalogue of deep sky objects in astronomy. It contains 7,840 objects, known as the NGC objects...

  • List of planetary nebulas

External links

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