IC 4406

IC 4406, sometimes known as the Retina Nebula,^[4] is a planetary nebula near the western border of the constellation Lupus, the Wolf. It has dust clouds and has the shape of a torus. Despite this, it looks somewhat rectangular because it is seen from its side as viewed from Earth, almost in the plane^[2] of its equator.

IC 4406

Emission nebula
Planetary nebula
Hubble Space Telescope view of IC 4406
Observation data: J2000 epoch
Right ascension	14h 22m 26.278s[1]
Declination	−44° 09′ 04.35″[1]
Distance	2.0 kly (600 pc)[2] ly
Constellation	Lupus
Physical characteristics
Absolute magnitude (V)	-0.3
Notable features	-
Designations	Retina Nebula[3]
See also: Lists of nebulae

Structure

IC 4406 is bipolar and appears to be a prolate spheroid with strong concentrations of material in its equator.^[3] This kind of structure is a natural product of a bipolar model.^[3] The knots of IC 4406 have a "lacy" appearance and have no ordered symmetry towards the central star.^[2] The knots have no tails.^[2] None of the features have bright edges.^[2] At least 5 faint ring-like structures, seen as arcs north and south of the main nebula, have been detected in Very Large Telescope observations.^[5]

The central star of the planetary nebula has a spectral type similar to that of a Wolf–Rayet star.^[6] An analysis of Gaia data suggests that it may be a binary system.^[7]

Gallery

• 
  IC 4406 seen with MUSE instrument and the Adaptive Optics Facility.^[8]

See also

• Planetary nebula

References

1. "SIMBAD Astronomical Database". Results for IC 4406. Retrieved 2006-12-19.
2. O'dell, C. R.; Balick, B.; Hajian, A. R.; Henney, W. J.; et al. (2003). "Knots in Planetary Nebulae". In S. J. Arthur & W. J. Henney (ed.). Revista Mexicana de Astronomía y Astrofísica (Serie de Conferencias). Winds, Bubbles, and Explosions: a conference to honor John Dyson, Pátzcuaro, Michoacán, México, September 9–13, 2002. Vol. 15. pp. 29–33. Bibcode:2003RMxAC..15...29O. Archived from the original on 2018-05-01. Retrieved 2006-12-19.
3. O'Dell, C. R.; Balick, B.; Hajian, A. R.; Henney, W. J.; Burkert, A. (2002). "Knots in Nearby Planetary Nebulae". The Astronomical Journal. 123 (6): 3329–3347. Bibcode:2002AJ....123.3329O. doi:10.1086/340726.
4. Chadwick, Stephen; Cooper, Ian (11 December 2012). Imaging the Southern Sky. Springer. p. 149. ISBN 978-1461447498.
5. Ramos-Larios, G.; Toalá, J. A.; Rodríguez-González, J. B.; Guerrero, M. A.; Gómez-González, V. M. A. (June 2022). "Rings and arcs around evolved stars - III. Physical conditions of the ring-like structures in the planetary nebula IC 4406 revealed by MUSE". Monthly Notices of the Royal Astronomical Society. 513 (2): 2862–2868. arXiv:2203.01254. Bibcode:2022MNRAS.513.2862R. doi:10.1093/mnras/stac605. hdl:10261/275661.
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. Chornay, N.; Walton, N. A.; Jones, D.; Boffin, H. M. J.; Rejkuba, M.; Wesson, R. (2021). "Towards a more complete sample of binary central stars of planetary nebulae with Gaia". Astronomy & Astrophysics. 648: A95. arXiv:2101.01800. Bibcode:2021A&A...648A..95C. doi:10.1051/0004-6361/202140288. S2CID 230770301.
8. "Cutting-edge Adaptive Optics Facility Sees First Light - Spectacular improvement in the sharpness of MUSE images". www.eso.org. Retrieved 4 August 2017.

External links

• Media related to IC 4406 at Wikimedia Commons