NGC 6337

NGC 6337
Emission nebula
Planetary nebula
Image of NGC 6337 with the VLT Survey Telescope. Green part of the image was taken with the H-alpha filter.
Observation data: J2000 epoch
Right ascension17h 22m 15.67s
Declination−38° 29 01.73
Apparent dimensions (V)0.783' (arcmin)
ConstellationScorpius
DesignationsGhostly Cheerio, Cheerio Nebula

NGC 6337, the Ghostly Cheerio or Cheerio Nebula, is a toroidal planetary nebula in the constellation Scorpius. It appears as a ring-shaped (annular) transparent nebula resembling a piece of the breakfast cereal Cheerios, hence the name. Filament and knots, and a faint shell surround the ring. Its magnitude is 11.90; its position in Scorpius is right ascension 17h 22m15.67s, declination -38° 29' 01.73". The Ghostly Cheerio has a redshift value of -0.000236.

There is convincing evidence that a binary nucleus exists at the center of the nebula, with masses of 0.6 and 0.3 M⊙, and a separation of ≤ 1.26 R⊙, indicating a probable common envelope phase. The Ghostly Cheerio's projected radial expansion is slow, averaging 1–2 kilometres per second (0.6–1.2 mi/s).