IC 418
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Planetary nebula IC 418 |
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| False color image: Red = ionized nitrogen (coldest gas) |
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| AladinLite | |
| Constellation | Hare |
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Position equinox : J2000.0 |
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| Right ascension | 05h 27m 28.2s |
| declination | -12 ° 41 ′ 50 ″ |
| Appearance | |
| Apparent brightness (visual) | 9.3 likes |
| Apparent brightness (B-band) | 10.7 likes |
| Angular expansion | 0.2 ′ |
| Central star | |
| designation | HD 35914 (BD −12 ° 1172, ZZ Leporis) |
| Apparent brightness | 10.2 mag |
| Spectral class | O7fp |
| Physical data | |
| distance | approx. 3000 ly (approx. 1000 pc ) |
| diameter | approx. 0.3 ly |
| history | |
| discovery | Williamina Fleming |
| Date of discovery | March 26, 1891 |
| Catalog names | |
| IC 418 • PK 215−24.1 • PN G215.2-24.2 • IRAS 05251-1244 | |
IC 418 is a galactic planetary nebula in the constellation Lepus .
Its distance is estimated to be about 3000 light years , its extent is about 0.3 light years.
IC 418 is also called Spirograph Nebula because of its similarity to the patterns produced by the geometric toy of the same name . This phenomenon is not currently understood. One suspects, however, a connection with the chaotic winds that emanate from the central star of the nebula. This is a variable star whose brightness changes unpredictably within a few hours.
Studies show that the current central star was a star similar to our sun a few million years ago . Just a few thousand years ago, nuclear fuel ran out and the star evolved into a red giant that eventually burned out and shed its outer shell. What remained was a white dwarf , whose ultraviolet light stimulates the atoms of the surrounding nebula and makes it glow.
Visual observation
The spirograph nebula can already be seen as a stellar-appearing object in a small telescope with an opening of 60 mm. If you choose a larger instrument with an aperture of approx. 6 "or more, this planetary nebula is already a very conspicuous object: A very bright central star is surrounded by a structureless, only slightly elliptical nebula that is very sharply delimited to the outside.
The nebula is relatively easy to find if you aim for the middle of the two “feet” of Orion Saiph (Kappa Orionis) and Rigel and move about 4 ° south from there. It is then about 2½ ° east of a bright group of stars in the constellation Lepus.
Sources and Links
- Axel M Quetz .: The distance of the spirograph nebula IC 418 . In: Stars and Space . 7/2009, Spektrum Verlag, ISSN 0039-1263
- IC 418 - STScI Press Release (English)
- SIMBAD query
Individual evidence
Attention: The sorting key “IC 0418” overwrites the previously used key “IC0418”.