| Constellation | Orion |
|---|---|
| Epoch | J2000 |
| Ra | [1] |
| Dec | [1] |
| Dist ly | 1,300 ± 160 ly (400 ± 50 pc) |
| Appmag v | 9.0[2] |
| Size v | 20′ × 15′[3] |
| Notes | NU Orionis |
| Names | De Mairan's Nebula, M43, NGC 1982[4] |
Messier 43 or M43, also known as De Mairan's Nebula and NGC 1982, is a star-forming nebula with a prominent H II region in the equatorial constellation of Orion. It was discovered by the French scientist Jean-Jacques d'Ortous de Mairan some time before 1731,[3] then catalogued by Charles Messier in 1769.[a] It is physically part of the Orion Nebula (Messier 42), separate from that main nebula by a dense lane of dust known as the northeast dark lane.[5] It is part of the much larger Orion molecular cloud complex.
The main ionizing star in this nebula is the quadruple star system NU Orionis (HD 37061), the focus of the H II region, 1,360 ± 30 ly (420 ± 9.2 pc) away.[6] This star system is not hot enough to produce significant amounts of [O III] emission, unlike the Trapezium in the Orion Nebula.[7]
The H II region is a roundish volume of ionized hydrogen. It has a diameter of about 4.5 arcminute, at its distance meaning it measures 2.1 ly (0.65 pc). The net (meaning omitting the star) hydrogen alpha luminosity of this region is 3.0 ± 1.1×1035 erg s−1; equivalent to 78 solar luminosity. There is a dark lane crossing the whole west-centre strip from north to south, known as the M43 dark lane, which forming a swirling belt extension to the south links to Orion's northeast dark lane. All of these resemble a mixture of smoke rising from a chimney and in watercolour broad and fine dark brushstrokes, at many wavelengths.
See also
References and footnotes
- ^ Sulentic, Jack W. et al. (1973), "The revised new catalogue of nonstellar astronomical objects", Tucson: University of Arizona Press, Bibcode:1973rncn.book.....S
- ^ "Messier 43". SEDS Messier Catalog. Retrieved 23 July 2024.
- ^ Adam, Len (2018), Imaging the Messier Objects Remotely from Your Laptop, The Patrick Moore Practical Astronomy Series, Springer, p. 209, Bibcode:2018imor.book.....A. ISBN 978-3319653853
- ^ "M 43". Retrieved November 25, 2018.
- ^ Simón-Díaz, S. et al. (June 2011), "A detailed study of the H ii region M 43 and its ionizing star", Astronomy & Astrophysics. 530: 13, arXiv:1103.3628. Bibcode:2011A&A...530A..57S. doi:10.1051/0004-6361/201116608. A57
- ^ Aschenbrenner, P. & Przybilla, N. (2024-11-01). "Quantitative spectroscopy of multiple OB stars - I. The quadruple system HD 37061 at the centre of Messier 43". Astronomy & Astrophysics. 691: A361. arXiv:2410.23229. doi:10.1051/0004-6361/202451878. ISSN 0004-6361
- ^ Odell, C. R. & Harris, Jessica (2010-09-08). "Spectrophotometry of the Huygens Region of the Orion Nebula, the Extended Orion Nebula, and M 43: Scattered Light Systematically Distorts Conditions Derived from Emission Lines". The Astronomical Journal. 140 (4): 985–1006. doi:10.1088/0004-6256/140/4/985. – via Space Telescope Science Institute (STScI)
External links
- "Messier 43", NASA, October 19, 2017, retrieved 2018-11-26
- Frommert, Hartmut & Kronberg, Christine (October 8, 2018), "Messier 43: De Mairan's Nebula, Companion of the Orion Nebula", Students for the Exploration and Development of Space (SEDS), retrieved 2018-11-26
- ^ On March 4