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File:NGC_246.jpg · Wikimedia Commons · See Wikimedia Commons
Q536591
Sign in to saveAlso known as skull nebula, pac-man nebula, Cetus ring, Caldwell 56, New General Catalogue 246
planetary nebula in the constellation Cetus
Key facts
- Right ascension
- 00 47 03.338
- Declination
- −11 ° 52 ′ 18.94 ″
- Distance
- 3,500 +720, −850 ly
- Apparent magnitude v
- 8 / 11.8 (central star)
- Apparent dimensions v
- 3.8 ′
- Constellation
- Cetus
- Radius
- 2-3 ly
- Designations
- Skull Nebula, Pac-Man Nebula, Caldwell 56, HIP 3678, PMN J0047-1152, 2E 178, PN VV 4, IRAS 00445-1207, MCT 0044-1208
via Wikipedia infobox
Wikidata facts
- Distance from Earth
- 475
- Radius
- 2
- Image
- N246s.jpg
Show 11 more facts
- spectral class
- PG1159
- Commons category
- NGC 246
- catalog code
- TIC 3905338
- apparent magnitude
- 12.87
- right ascension component of proper motion
- -47
- time of discovery or invention
- 1785-11-27
- right ascension
- 11.76392533469125
- declination
- -11.87193752949389
- parallax
- 1.59
- radial velocity
- -15.70
- declination component of proper motion
- 3
Sources (1)
via Wikidata · CC0
~2 min read
Article
NGC 246 (also known as the Skull Nebula or Caldwell 56) is a planetary nebula in the constellation Cetus. It was discovered in 1785 by William Herschel. The nebula and the stars associated with it are listed in several catalogs, as summarized by the SIMBAD database.
The nebula is roughly 3,500+720 −850 light-years away. NGC 246's central star is the 12th magnitude white dwarf HIP 3678 A. In 2014, astronomers discovered a second companion to NGC 246's central star, which has a comoving companion star called HIP 3678 B. The second companion star, a red dwarf known as HIP 3678 C, was discovered using the European Southern Observatory's Very Large Telescope. This makes NGC 246 the first planetary nebula to have a hierarchical triple star system at its center. It is currently the only known example of a planetary nebula with more than two central stars.