Fly (constellation)
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Constellation fly |
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|---|---|
  |
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| Latin name | Musca |
| Latin genitive | Muscae |
| Abbreviation | Mus |
| Right ascension | 11 h 19 m 26 s to 13 h 51 m 08 s |
| declination | −75 ° 41 ′ 46 ″ to −64 ° 38 ′ 17 ″ |
| surface | 138.355 deg² rank 77 |
| Completely visible | 14.0 ° N to 90 ° S |
| Observation time for Central Europe | not visible |
| Number of stars brighter than 3 mag | 1 |
| Brightest star (size) | α Mus (2.69) |
| Meteor streams |
no |
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Neighboring constellations ( clockwise from north ) |
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| swell | IAU , |
The fly ( Latin Musca ) is a constellation of the southern sky.
description
The fly is a small but easily recognizable constellation just south of the Southern Cross . It contains a conspicuous star of the 2nd magnitude and a compact trapezoid of only slightly weaker stars.
The ribbon of the Milky Way runs through the constellation . What is striking is an extended dark cloud , the coal sack , the southern part of which protrudes into the fly. In the prism binoculars , the region of the sky around the fly is a magnificent sight.
history
The fly is one of the twelve new constellations introduced by the Dutch navigators Pieter Dirkszoon Keyser and Frederick de Houtman at the end of the 16th century . Johann Bayer took it over as a bee (Apis) in his 1603 sky atlas Uranometria .
1752 they named Nicolas Louis de Lacaille in La Mouche to ( Planisphère des Étoiles Australes , dated 1752, published 1756), Latinized Musca on the Coelum Australe Stelliferum (posthumously published in 1763). Later it is also called Musca Australis in contrast to the Musca Borealis in Aries after Johannes Hevelius (which goes back to Plancius ' bee ).
After Johann Elert Bode's atlases in 1782, however, the use of the northern fly ceases , and today it is once again called Musca in a nutshell .
On old star maps, the tongue of the neighboring chameleon flicks in the direction of the fly.
Celestial objects
Stars
| B. | Names or other designations | Size (mag) | Lj | Spectral class |
|---|---|---|---|---|
| α | 2.69 | 306 | B2 IV-V | |
| β | 3.04 | 311 | B2 V | |
| δ | 3.61 | 91 | K2 III | |
| λ | 3.63 | 128 | A7 III | |
| γ | 3.84 | 324 | B5 V | |
| ε | 4.0 to 4.3 | 302 | M5 III | |
| μ | 4.75 | 432 | K4 III | |
| η | 4.79 | 406 | B8 V | |
| HR 5002 | 4.86 | K2 Ib-II | ||
| HR 4549 | 4.89 | 338 | B4 V | |
| HR 4538 | 4.98 | G5 Ib | ||
| ι | 5.04 | 225 | K0 III | |
| HR 4401 | 5.09 | 475 | B5 | |
| ζ 2 | 5.15 | |||
| HR 4617 | 5.17 | 438 | K2 II | |
| HR 4604 | 5.34 | 339 | A0 V | |
| θ | 5.44 | WC6 + O9 |
α Muscae is a blue supergiant 306 light years away with 20,000 times the luminosity of our sun. At a distance of 2600 AU there is a faint companion star that will orbit it in 45,000 years.
Delta Muscae is a spectral class K2 III star 91 light-years away .
In Theta Muscae is the second brightest known Wolf-Rayet star .
Double stars
| system | Sizes (mag) | distance |
|---|---|---|
| β | 3.7 / 4.0 | 1.3 " |
Beta Muscae is a binary star system 311 light years away. The two components belong to the spectral classes B2 and B3. To resolve the system into single stars, you need a medium-sized telescope .
Variable stars
| object | Size (mag) | period | Type |
|---|---|---|---|
| α | 2.69 | 2.2 hours | Cepheid |
| ε | 4.0 to 4.3 | 40 days | Semi-regularly variable |
The main star of the system, Alpha Muscae, pulsates gently, changing its brightness by about 1% over a period of 2.2 hours. It belongs to the variable stars of the Cepheid type .
Epsilon Muscae is a semi-regularly variable star 302 light-years away and fluctuating in brightness over a period of about 40 days. It is a red giant of the spectral class M5 III.
Foggy objects
| NGC | other | Size (mag) | Type | Surname |
|---|---|---|---|---|
| Dark cloud | Coal sack | |||
| 4372 | 7.8 | Globular clusters | ||
| 4463 | 7.2 | Open star cluster | ||
| 4815 | 8.6 | Open star cluster | ||
| 4833 | 7.4 | Globular clusters | ||
| 5189 | 9.7 | Planetary nebula |
The coal sack is an extensive dark cloud 600 light years away.
NGC 4833 is a globular cluster 18,000 light years away. In a middle telescope, the edge area can be resolved into single stars.
The planetary nebula NGC 5189 is the ejected gas envelope of a star at a distance of 2600 light years. The nebula has an unusually elongated shape that can be seen even in a small telescope.
IC 4191 is a planetary nebula of in 1907 by the astronomer Williamina Fleming was discovered
See also
Individual evidence
- ↑ Lacaille's southern planisphere of 1756 - illustration in Jan Ridpath's Startales
