Pegasus (constellation)
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Pegasus constellation |
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| Latin name | Pegasus |
| Latin genitive | Pegasi |
| Abbreviation | Peg |
| Right ascension | 21 h 08 m 43 s to 00 h 14 m 58 s |
| declination | + 2 ° 19 ′ 32 ″ to + 36 ° 36 ′ 25 ″ |
| surface | 1120.794 deg² rank 7 |
| Completely visible | 90 ° N to 53.6 ° S |
| Observation time for Central Europe | autumn |
| Number of stars brighter than 3 mag | 5 |
| Brightest star (size) | Enif (2.39) |
| Meteor streams | |
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Neighboring constellations ( clockwise from north ) |
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| swell | IAU , |
 The constellation of Pegasus as seen with the naked eye |
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The Pegasus is a constellation just north of the celestial equator . It is best seen in the autumn evening sky and is noticeable because four of its main stars form approximately a square.
description
Pegasus is an expansive constellation in the autumn sky that is said to represent an upside-down flying horse. The stars γ, α, β and Sirrah form its body - where Sirrah actually belongs to Andromeda . The stars ζ, θ and ε shape the head and neck of the horse. These stars lead to the globular cluster M 15 .
history
Pegasus is one of the 48 constellations of ancient astronomy mentioned by Ptolemy .
Helvetios (51 Pegasi) was the first main sequence star (after our sun ) in which a planetary system was detected. Using the radial velocity method , the exoplanet Dimidium (51 Pegasi b) was discovered in 1995 , which has about half the mass of Jupiter .
mythology
The Greek mythology after was Pegasus the winged horse that the neck of the deadly Medusa sprang after Perseus struck off her head.
The winged horse escaped and was later captured by Bellerophon , who had numerous adventures with him. But when Bellerophon wanted to soar to the gods, he incurred the wrath of Zeus . Zeus sent out a horsefly that stung Pegasus. The horse shied and threw off Bellerophon, who landed roughly on the ground. Pegasus flew on to Olympus and since then has been carrying the lightning bolts of Zeus.
Celestial objects
Stars
| B. | F. | Names or other designations | size | Lj | Spectral class |
|---|---|---|---|---|---|
| ε | 8th | Enif | 2.39 m | 673 | K2 Ib |
| β | 53 | Scheat | 2.4 to 3.0 m | 199 | M222 II-III |
| α | 54 | Markab , Menkib | 2.49 m | 140 | B9.5 III |
| γ | 88 | Algenib | 2.80 to 2.86 m | 333 | B2 IV |
| η | 44 | Matar | 2.93 m | 215 | G2 II-III |
| ζ | 42 | Homam | 3.41 m | 209 | B8.5 V |
| μ | 48 | Sadalbari | 3.51 m | 117 | M2 III |
| θ | 26th | Biham | 3.52 m | 97 | A2V |
| ι | 24 | 3.77 m | 38 | F5 V | |
| λ | 47 | 3.97 m | 395 | G8 II-III | |
| 1 | 4.08 m | 154 | K1 III | ||
| κ | 10 | Jih | 4.14 m | 115 | F5 IV |
| ξ | 46 | 4.20 m | 53 | F7 V | |
| χ | 89 | 4.20 m | 53 | F7 V | |
| π 2 | 29 | 4.28 m | 252 | F5 III | |
| υ | 22nd | 4.42 m | 173 | F8IV | |
| 9 | 4.43 m | 901 | G5 Ib | ||
| 2 | 4.52 m | 443 | M1 III | ||
| 55 | 4.54 m | 322 | M2 III | ||
| 7th | 4.54 m | 178 | G8 III | ||
| τ | 62 | Salm , curb | 4.6 m | about 160 | A5 IV |
| ψ | 84 | 4.63 m | 433 | M3 III | |
| 56 | 4.76 m | 537 | K0 Iip | ||
| 35 | 4.78 m | 160 | K0 III | ||
| 32 | 4.78 m | 607 | B9 III | ||
| ο | 43 | 4.80 m | 305 | A1 IV | |
| 31 | 4.82 m | 971 | B2 IV-V | ||
| ν | 22nd | 4.86 m | 263 | K4 III | |
| ρ | 50 | 4.91 m | 282 | A1V | |
| 78 | 4.93 m | 235 | K0 III | ||
| 72 | 4.97 m | 548 | K4 III | ||
| 57 | GZ Pegasi | 5.05 m | 762 | M4 IIIs + | |
| φ | 81 | 5.06 m | 437 | M2 III | |
| 14th | 5.07 m | 303 | A1 Vs | ||
| 77 | 5.09 m | 818 | M2 III | ||
| 16 | 5.09 m | 512 | B3 V | ||
| 66 | 5.09 m | 330 | K3 III | ||
| σ | 49 | 5.16 | 88 | F7 IV | |
| 59 | 5.15 m | 253 | A5 Vn | ||
| 12 | 5.29 m | 1129 | K0 Ib | ||
| 7th | 5.30 m | 522 | M2 III | ||
| 82 | HT | 5.30 m | 188 | A4 Vn | |
| 71 | HW | 5.33 m | 575 | M5 IIIa | |
| MR | 5.34 m | 256 | K2 III | ||
| 13 | 5.34 m | 109 | F2 III-IV | ||
| 64 | 5.35 m | 834 | B6 III | ||
| 30th | 5.37 m | 919 | B5 IV | ||
| 58 | 5.39 m | 619 | B9 III | ||
| 5 | 5.46 m | 321 | F1 IV | ||
| 75 | KS Pegasi | 5.49 m | 239 | A1 Vn | |
| 51 | Helvetios | 5.49 m | 50.1 | G5 V |
α Pegasi is a bluish shining star of the spectral class B9, 140 light years away .
The name Markab of the star α Pegasi is of ancient Arabic origin and means "saddle".
Multiple stars
| system | Sizes | distance |
|---|---|---|
| α | 2.5 / 7.8 / 11 m | 138/82 " |
| 1 | 4.2 / 9.3 m | 36 " |
| 37 | 5.8 / 7.1 m | 0.6 " |
| 72 | 5.7 / 5.8 m | 0.5 " |
ε Pegasi is a triple star system 673 light years away. The main star is extremely luminous and has 11 times the mass and 175 times the diameter of our sun . In 1972 the star showed an outbreak of brightness, whereby it became strikingly bright at 0.70 m . At a distance of 138 arcseconds there is a 7.8 m bright companion star that is already visible in the prism binoculars . A telescope is required to observe the third component .
The Arabic name Enif is derived from "Maul" (the horse).
Variable stars
| star | m | period | Type |
|---|---|---|---|
| β pegasi | 2.31 to 2.74 | 43.3 days | Semi-regular variable star |
| γ pegasi | 2.82 to 2.86 | 0.1518 days (3.64 hours) | Beta Cephei star |
| LL Pegasi | 9.64 to 11.6 (K) | 696 days | Mira star |
β Pegasi is a variable star 199 light years away. It is a red giant 200 times the diameter of the sun. Its brightness fluctuates between 2.4 and 3.0 m at irregular intervals .
The Arabic name Scheat means "front leg" (of the horse).
γ Pegasi is a pulsation-variable star of the Beta-Cephei type, 333 light-years away . Its brightness changes slightly over a period of 3 hours and 47 minutes.
The Arabic name Algenib means "flank" (of the horse).
Messier and NGC objects
| NGC 7331 and Stephan's Quintet photographed through a 20 cm amateur telescope. | |||
|---|---|---|---|
| Messier (M) | NGC | other | size | Type | Surname |
|---|---|---|---|---|---|
| 15th | 7078 | 6.0 m | Globular clusters | ||
| 7217 | 10.1 m | Galaxy | |||
| 7317 | Galaxy | ||||
| 7318B | Galaxy | ||||
| 7319 | Galaxy | ||||
| 7320 | Galaxy | ||||
| 7331 | 9.5 m | Galaxy | |||
| 7479 | 10.9 m | Galaxy | |||
| 7673 | Galaxy |
The globular cluster M 15 is about 30,000 light years away. In the binoculars it appears as a misty spot. With a telescope with an opening of 15 cm or more, the star cluster can be broken down into individual stars.
NGC 7331 is a spiral galaxy of type Sb about 60 million light years away. The galaxy can be observed with a telescope from 10 cm aperture.
The galaxies NGC 7317 , NGC 7318A , NGC 7318B , NGC 7319, and NGC 7320 form a group called Stephan's Quintet . Due to their distance of about 380 million light years, the galaxies have a low brightness. A telescope with an opening of 20 cm or more is required to observe them.
NGC 7479 is a barred spiral galaxy .
