Sh 2-27

Sharpless 2-27
Emission nebula
H II region
Sh 2-27 (pink) embedded within molecular clouds (green and blue), imaged by the Northern Sky Narrowband Survey.
Observation data: J2000 epoch
Right ascension16h 35m 56s
Declination−12° 43′ 05″
Distance440  ly
Apparent magnitude (V)17.3
Apparent dimensions (V)10° x 15°
ConstellationOphiuchus
Physical characteristics
Radius78 ly
Dimensions480' x 480'
DesignationsLBN 24, Gum 73, Cobold Nebula, Zeta Ophiuchi Nebula
See also: Lists of nebulae

Sh 2-27 (also known as the Cobold Nebula or the Zeta Ophiuchi Nebula), is an emission nebula in the constellation Ophiuchus. It is ionized by the star Zeta Ophiuchi, which lies near its center. The star is a runaway that produces a notable bow shock.

The bow shock around the runaway star Zeta Ophiuchi, imaged by NASA’s Spitzer Space Telescope.

The nebula is embedded within the Rho Ophiuchi cloud complex and can be classified as an H II region. Its distance of only about 440 light-years, determined from Gaia parallax measurements of Zeta Ophiuchi , makes it one of the closest known emission nebulae. This proximity is also the reason for its large apparent size of approximately 15° × 10°, even though the nebula itself is relatively faint.

References

  1. ↑ "SIMBAD query result".
  2. 1 2 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. ↑ "Sharpless (Sh2) - Astrobasics". 13 September 2022.
  4. ↑ "Sharpless 27".
  5. ↑ "CCD Images of the Sharpless Catalog".
  6. ↑ "Sh 2-27".