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'''Microscopium''' {{IPAc-en|ˌ|m|aɪ|k|r|ə|ˈ|s|k|ɒ|p|i|əm}} is a small [[constellation]] in the southern sky, defined in the 18th century by [[Nicolas Louis de Lacaille]]. |
'''Microscopium''' {{IPAc-en|ˌ|m|aɪ|k|r|ə|ˈ|s|k|ɒ|p|i|əm}} is a small [[constellation]] in the southern sky, defined in the 18th century by [[Nicolas Louis de Lacaille]]. Its brightest star is [[Gamma Microscopii]] of magnitude 4.68. |
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==History== |
==History== |
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Revision as of 09:08, 19 November 2013
| Constellation | |
 | |
| Abbreviation | Mic |
|---|---|
| Genitive | Microscopii |
| Pronunciation | /ˌmaɪkrəˈskɒpiəm/, genitive /ˌmaɪkrəˈskɒpiaɪ/ |
| Symbolism | the Microscope |
| Right ascension | 21 |
| Declination | −36 |
| Quadrant | SQ4 |
| Area | 210 sq. deg. (66th) |
| Main stars | 5 |
| Bayer/Flamsteed stars | 13 |
| Stars with planets | 1 |
| Stars brighter than 3.00m | 0 |
| Stars within 10.00 pc (32.62 ly) | 2 |
| Brightest star | γ Mic (4.67m) |
| Messier objects | none |
| Meteor showers | ????? ????? |
| Bordering constellations | Capricornus Sagittarius Telescopium (corner) Indus Grus Piscis Austrinus |
| Visible at latitudes between +45° and −90°. Best visible at 21:00 (9 p.m.) during the month of September. | |
Microscopium /ˌmaɪkrəˈskɒpiəm/ is a small constellation in the southern sky, defined in the 18th century by Nicolas Louis de Lacaille. Its brightest star is Gamma Microscopii of magnitude 4.68.
History
The stars that now comprise Microscopium may formerly have belonged to the hind feet of Sagittarius.[1] However, this is uncertain as, while its stars seem to be referred to by Al-Sufi as having been seen by Ptolemy, Al-Sufi does not specify their exact positions.[2]
Its name is Latin for microscope; it was called this due to its visual similarity to 18th century microscope.[3] Its stars are very faint and hardly visible from most of the non-tropical northern hemisphere.
The former constellation Neper, representing an auger, may have been located in or near modern-day Microscopium. However, this connection is disputed.[3]
Characteristics
Microscopium is a small constellation bordered by Capricornus to the north, Piscis Austrinus and Grus to the west, Sagittarius to the east, Indus to the south, and touching on Telescopium to the southeast. The recommended three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is 'Mic'.[4] The official constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of 4 segments. In the equatorial coordinate system, the right ascension coordinates of these borders lie between 20h 27.3m and 21h 28.4m , while the declination coordinates are between −27.45° and −45.09°.[5] Given that its brightest stars are of fifth magnitude, the constellation is invisible to the naked eye in areas with polluted skies.[6]
Notable features
The brightest star is Gamma Microscopii, which has an apparent visual magnitude of 4.68. It is a yellow giant of spectral class G6 III.[7] Lying 381 light years away,[8] It depicts the eyepiece of the microscope.[9] Alpha Microscopii is also a yellow giant, though in this case a variable star, which ranges between apparent magnitudes 4.88 and 4.94. It is of spectral type G7III.[10] Alpha has a 10th magnitude companion, visible in small telescopes.[8] Epsilon Microscopii lies 165 light years away, and is a blue-white main sequence star of apparent magnitude 4.7,[8] and spectral type A1V.[11] Theta 1 and Theta 2 Microscopii make up a wide double whose components are splittable to the naked eye. Both are white A-class magnetic spectrum variable stars with strong metallic lines, similar to Cor Caroli. They mark the constellation's specimen slide.[9]
Many notable objects are too faint to be seen with the naked eye. AX Microscopii, better known as Lacaille 8760, is a red dwarf which lies only 12.9 light years from our solar system.[12] WASP-7 is a star of magnitude 9.54 which has been discovered to have an exoplanet WASP-7b, and AU Microscopii is a young star which appears to be a solar system in the making with a debris disk. BO Microscopii is a rapidly rotating star, and PSR J2144-3933 is an unusual pulsar with an unusually long rotation period.
NGC 6925 is a barred spiral galaxy of apparent magnitude 11.3 which is lens-shaped as it lies almost edge on to us. It lies 3.7 degrees westnorthwest of Alpha Microscopii.[13] NGC 6923 lies nearby and is a magnitude fainter still.[14]
References
- Citations
- ^ G. Rubie (1830) The British Celestial Atlas, p. 37 (ebook available at https://play.google.com/store/books/details?id=KDEAAAAAQAAJ&rdid=book-KDEAAAAAQAAJ&rdot=1).
- ^ J. Ellard Gore, Astronomical Curiosities:Facts and Fallacies (Google e-Book) (ISBN 1465524428, 9781465524423).
- ^ a b Staal 1988, p. 233.
- ^ Russell, Henry Norris (1922). "The new international symbols for the constellations". Popular Astronomy. 30: 469. Bibcode:1922PA.....30..469R.
- ^ "Microscopium, constellation boundary". The Constellations. International Astronomical Union. Retrieved 13 July 2012.
{{cite journal}}: CS1 maint: postscript (link) - ^ Kambič, Bojan (2009). Viewing the Constellations with Binoculars. Springer. p. 341. ISBN 0387853545.
- ^ Gamma Mic, Stars, Jim Kaler. Accessed on line July 13, 2012.
- ^ a b c Ridpath, Ian; Tirion, Wil (2007). Stars and Planets Guide. Princeton: Princeton University Press. pp. 184–85. ISBN 978-0-691-13556-4.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ a b Motz, Lloyd (1991). The Constellations: An Enthusiast's Guide to the Night Sky. London, United Kingdom: Aurum Press. pp. 369–70. ISBN 1-85410-088-2.
{{cite book}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ "Alpha MicroscopiI". SIMBAD. Retrieved 15 July 2012.
- ^ "Epsilon MicroscopiI". SIMBAD. Retrieved 15 July 2012.
- ^ Croswell, Ken (2003), "The Brightest Red Dwarf", Sky & Telescope: 32, retrieved 15 July 2012
{{citation}}: Unknown parameter|month=ignored (help) - ^ Bakich, Michael E. (2010). 1001 Celestial Wonders to See Before You Die: The Best Sky Objects for Star Gazers. Patrick Moore's Practical Astronomy Series. Springer. p. 289. ISBN 1-4419-1776-4.
- ^ Moore, Patrick; Tirion, Wil (1997). Cambridge Guide to Stars and Planets. Cambridge, United Kingdom: Cambridge University Press. p. 210. ISBN 0-521-58582-1.
{{cite book}}: CS1 maint: multiple names: authors list (link)
- References
- Staal, Julius D.W. (1988), The New Patterns in the Sky, McDonald and Woodward Publishing Company, ISBN 0-939923-04-1
External links
