IC 4406

From Wikipedia, the free encyclopedia

Observation data (Epoch J2000)
IC 4406
HST view of IC 4406
Right ascension	14^h 22^m 26.278^s^[1]
Declination	-44° 09′ 04.35″^[1]
Distance	2.0 kly (600 pc)^[2]
Apparent dimensions (V)	30″^{[citation needed]}
Constellation	Lupus
Physical characteristics
Radius	0.13 × 0.45 ly^{[citation needed]}
Absolute magnitude (V)	-0.3
Notable features	-
Other designations	Retina Nebula^[3]
See also: Planetary nebula, Lists of nebulae

IC 4406 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.

[edit] 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]

[edit] References

^ ^a ^b SIMBAD Astronomical Database. Results for IC 4406. Retrieved on 2006-12-19.
^ ^a ^b ^c ^d ^e O'dell, C. R.; Balick, B.; Hajian, A. R.; Henney, W. J.; Burkert, A. (2003). "Knots in Planetary Nebulae". Winds, Bubbles, and Explosions: a conference to honor John Dyson, Pátzcuaro, Michoacán, México, September 9-13, 2002 (Eds. S. J. Arthur & W. J. Henney) Revista Mexicana de Astronomía y Astrofísica (Serie de Conferencias) (http://www.astroscu.unam.mx/~rmaa/) 15: 29–33.
^ ^a ^b ^c 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. doi:10.1086/340726.