Eskimo mist

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Planetary Nebula
Data of the Eskimo Nebula
Ngc2392.jpg
The Eskimo Nebula captured by the Hubble Space Telescope
AladinLite
Constellation Twins
Position
equinox : J2000.0
Right ascension 07h 29m 10.7s
declination + 20 ° 54 ′ 43 ″
Appearance
Apparent brightness  (visual) 9.1 mag 
Apparent brightness  (B-band) 9.9 likes 
Angular expansion 0.9
Central star
designation HD 59088 
Physical data
Redshift +0.000281 
Radial velocity +84.2 km / s 
distance 3000 ly 
history
discovery Wilhelm Herschel
Date of discovery January 17, 1787
Catalog names
 NGC  2392 •  PK  197 + 17.1 •  GC  1532 •  H  IV 45 •  h  450 •

The Eskimo Nebula , NGC 2392 , is a planetary nebula in the constellation Gemini . It has a size of 0.8 '× 0.7' and an apparent magnitude of 9.1 mag, making it easy to observe with smaller telescopes. The nebula is around 3,000  light years from the solar system with an extension of 0.7 light years.

The nebula was formed about 10,000  years ago when the sun-sized central star shed its outer shell in an eruption.
Studies have shown that the central star is surrounded by two concentric gas envelopes that expand at different speeds. The shells are stimulated to glow by the strong radiation from the very hot central star.

The central star is an O8 dwarf star with about 40 times the luminosity of the sun. The absolute brightness is given as about +0.7 mag and the surface temperature is about 40,000 Kelvin.

In reality, NGC 2392 is probably not as round as it looks, but rather bipolar in shape, whereby we look into its polar axis.

Appearance

A telescope is necessary to observe the Eskimo Nebula . It can be seen in good binoculars , but only as a weak point of light. Even in a small telescope with an opening of around 10 cm, the Eskimo Nebula can be seen as a small disk. It can be helpful to use a mist filter . With larger openings, interesting features can then be seen, such as the division into two bowls and the arch, which looks like the hood of an Eskimo. With telescope openings larger than 50 cm, which are unusual among most amateurs, you can try your hand at a challenge: On the opposite side there is a dark place in a fragment of gas called a bridge . In addition to a large telescope, perfect conditions for seeing are necessary for successful sighting , as they can only be found in the high mountains in Central Europe.

Web links

Commons : Eskimonebel  - Collection of images, videos and audio files

Individual evidence

  1. ↑ NASA / IPAC EXTRAGALACTIC DATABASE
  2. ↑ a b SEDS: NGC 2392
  3. ↑ SIMBAD database
  4. ↑ Seligman