Planetary Nebula M2-9
From Wikipedia, the free encyclopedia
-
"Butterfly Nebula" redirects here. For other uses, see Butterfly Nebula (disambiguation).
| Planetary nebula | Lists of nebulae |
|---|---|
 |
|
| Observation data (Epoch J2000.0) |
|
| Right ascension | 17h 05m 37.95s |
| Declination | -10° 08′ 34.6" |
| Distance | 2100 ly |
| Apparent magnitude (V) | 12.06 |
| Apparent dimensions (V) | 55 × 18 arcsecs |
| Constellation | Ophiuchus |
| Physical characteristics | |
| Radius | 0.5 ly |
| Absolute magnitude (V) | - |
| Notable features | Bipolar outflow, Bipolar nebula |
| Other designations | Twin Jet Nebula, Wings of a Butterfly Nebula |
M2-9 (also known as Wings of a Butterfly Nebula or just Butterfly Nebula, and Twin Jet Nebula) is a protoplanetary nebula. This bipolar nebula takes the peculiar form of twin lobes of material that emanate from a central star. Astronomers have dubbed this object as the Twin Jet Nebula because of the polar jets believed to cause the shape of the lobes. Its form also resembles the wings of a butterfly, for which it is sometimes referred as the Wings of a Butterfly Nebula.
M2-9 was discovered by Rudolph Minkowski in 1947. The M in M2-9 does not stand for Messier object. The nebula was imaged by the Hubble Space Telescope in the 1990s.
The Wings of a Butterfly Nebula is about 2,100 light-years away from Earth in the direction of the constellation Monoceros. The total diameter of the nebula is about one-third of a light-year, or 2 trillion miles.
It represents the spectacular "last gasp" [citation needed] of a binary star system at the nebula's center. One component of this binary is the hot core of a star that reached the end of its main-sequence life cycle, ejected most of its outer layers and became a red giant, and is now contracting into a white dwarf. Early in its life the main component of the system was believed to be a sun-like star.
This central star is one of a very closely orbiting pair - the smaller star may even have been engulfed by the other's expanding stellar atmosphere. The resulting interaction has created the stunning protoplanetary nebula.
The nebula has inflated dramatically [citation needed] due to a fast stellar wind, blowing out into the surrounding disk and inflating the large, wispy hourglass-shaped wings perpendicular to the disk. These wings produce the butterfly appearance when seen in projection.
Astronomers theorize that the gravity of one star pulls some of the gas from the surface of the other and flings it into a thin, dense disk extending into space [citation needed]. Such a disk can successfully account for the jet-exhaust-like appearance of M2-9 [citation needed].
[edit] See also
[edit] External links
- Smithsonian/NASA ADS Astronomy/Planetary Abstract Service
- NASA APOD - M2-9: Wings of a Butterfly Nebula
[edit] References
- STScI. Hubble Witnesses the Final Blaze of Glory of Sun-Like Stars. Press release: Space Telescope Science Institute. December 17, 1997.
- Astrophysical Journal. The near-infrared structure and spectra of the bipolar nebulae M2-9 and AFGL 2688: The role of ultraviolet pumping and shocks in molecular hydrogen excitation. Authors: Hora, J. L. & Latter, W. B.
