Astronomy:Lemon Slice Nebula
| Emission nebula | |
|---|---|
| Planetary nebula | |
 Image of IC 3568 based on HST data | |
| Observation data: J2000 epoch | |
| Right ascension | 12h 33m 06s |
| Declination | +82° 34′ 00″ |
| Distance | Roughly 4.5⋅103 ly |
| Apparent magnitude (V) | 12.3 |
| Constellation | Camelopardalis |
| Physical characteristics | |
| Radius | Core: 0.2 ly |
| Designations | IC 3568, Perek-Kohoutek 123+34.1 (PK 123+34.1),[1] HD 109540 (central star)[2] |
IC 3568 is a planetary nebula that is 1.3 kiloparsecs (4500 ly) away from Earth in the constellation of Camelopardalis (just 7.5 degrees from Polaris). It is a relatively young nebula and has a core diameter of only about 0.4 light years. It was dubbed the Lemon Slice Nebula by Jim Kaler, due to its appearance in one false-colour image from the Hubble Space Telescope.[3][4] The Lemon Slice Nebula is one of the most simple nebulae known, with an almost perfectly spherical morphology. The core of the nebula does not have a distinctly visible structure in formation and is mostly composed of ionized helium.[5] A faint halo of interstellar dust surrounds the nebula. The central star of the planetary nebula is an O-type star with a spectral type of O(H)3.[6]
IC 3568 was discovered on August 31, 1900[7] by the American astronomer Robert Grant Aitken while using Lick Observatory's 12" Clark Refractor. While examining Comet Borrelly-Brooks, he found that the star BD +83° 357 in Camelopardalis is surrounded by a small circular nebula. This was confirmed with the observatory's 36" Refractor the next night. IC 3568 was misclassified as a compact galaxy in the Uppsala General Catalogue, as UGC 7731.[8]
See also
- NGC 40 (the Bow-Tie Nebula in Cepheus)
References
- ↑ The Deep Sky Field Guide to Uranometria 2000.0, Chart 9 (Murray Cragin, James Lucyk, Barry Rappaport), Willmann-Bell, 1993
- ↑ Sky Catalogue 2000.0, Volume 2: Double Stars, Variable Stars and Nonstellar Objects (edited by Alan Hirshfeld and Roger W. Sinnott, 1985), page 308
- ↑ IC 3568
- ↑ Portal to the Universe.org
- ↑ "starrycritters.com". http://www.starrycritters.com/a-slice-of-lemon/.
- ↑ González-Santamaría, I.; Manteiga, M.; Manchado, A.; Ulla, A.; Dafonte, C.; López Varela, P. (2021). "Planetary nebulae in Gaia EDR3: Central star identification, properties, and binarity". Astronomy & Astrophysics 656: A51. doi:10.1051/0004-6361/202141916. Bibcode: 2021A&A...656A..51G.
- ↑ Courtney Seligman: Closeup on IC 3568, the Lemon Slice Nebula
- ↑ Wolfgang Steinicke: Lick Observatory with 36" and 12" Refractor telescopes, used by Robert Grant Aitken during the discovery of IC 3568
External links
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