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
Emission nebula
Planetary nebula
Image of IC 3568 based on HST data
Observation data: J2000 epoch
Right ascension12h 33m 06s
Declination+82° 34′ 00″
DistanceRoughly 4.5⋅103 ly
Apparent magnitude (V)12.3
ConstellationCamelopardalis
Physical characteristics
RadiusCore: 0.2 ly
DesignationsIC 3568, Perek-Kohoutek 123+34.1 (PK 123+34.1),[1] HD 109540 (central star)[2]
See also: Lists of nebulae
False color image of the bright central region of IC 3568. This is the image that gave the nebula its common name.

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 edit

  • NGC 40 (the Bow-Tie Nebula in Cepheus)

References edit

  1. ^ The Deep Sky Field Guide to Uranometria 2000.0, Chart 9 (Murray Cragin, James Lucyk, Barry Rappaport), Willmann-Bell, 1993
  2. ^ Sky Catalogue 2000.0, Volume 2: Double Stars, Variable Stars and Nonstellar Objects (edited by Alan Hirshfeld and Roger W. Sinnott, 1985), page 308
  3. ^ IC 3568
  4. ^ Portal to the Universe.org
  5. ^ "starrycritters.com". Archived from the original on 2015-04-02. Retrieved 2013-07-29.
  6. ^ 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. arXiv:2109.12114. Bibcode:2021A&A...656A..51G. doi:10.1051/0004-6361/202141916. S2CID 237940344.
  7. ^ Courtney Seligman: Closeup on IC 3568, the Lemon Slice Nebula
  8. ^ Wolfgang Steinicke: Lick Observatory with 36" and 12" Refractor telescopes, used by Robert Grant Aitken during the discovery of IC 3568

External links edit

  •   Media related to IC 3568 at Wikimedia Commons