Berenike's hair
|
Constellation Haar der Berenike |
|
|---|---|
  |
|
| Latin name | Coma Berenices |
| Latin genitive | Comae Berenices |
| Abbreviation | Com |
| Right ascension | 11 h 58 m 25 s to 13 h 36 m 07 s |
| declination | + 13 ° 18 ′ 14 ″ to + 33 ° 18 ′ 27 ″ |
| surface | 386,475 deg² rank 42 |
| Completely visible | 90 ° N to 57.2 ° S |
| Observation time for Central Europe | spring |
| Number of stars brighter than 3 mag | 0 |
| Brightest star (size) | Tiara (4.26) |
| Meteor streams | |
|
Neighboring constellations ( clockwise from north ) |
|
| swell | IAU , |
The hair of Berenike , technically Coma Berenices , Coma for short ( Latin coma , head hair ), abbreviation Com , is a constellation in the northern sky between the lion and the bear guardian .
description
Coma Berenices is an inconspicuous constellation, the area of which borders on five other constellations. The three brightest stars - α, β and γ Comae Berenices - almost reach the 4th magnitude , with all others the apparent brightness is below 4.5 mag. To the naked eye, this collection can faint star between the adjacent distinctive constellations Leo (Leo) and Bootes watch in a dark moonless night best (boat). In Central Europe they are quite high in the spring sky , but can hardly be seen when the sky is polluted with light . Many of the stars belong to the Coma star cluster ( Mel 111), an open star cluster 260 light years away .
If you look in the direction of Coma Berenices, you look in the direction of the galactic north pole of our Milky Way . Since almost no gas and dust clouds of the Milky Way obstruct the view in this direction of view, many distant galaxies can be observed with the telescope . The so-called Coma galaxy cluster ( Abell 1656) is an extremely rich galaxy cluster with more than 1000 identified galaxies at a distance of over 300 million light years . In the starry sky, its central area extends over 2 °. In the southern part of the constellation Coma there are some closer and brighter single galaxies, 20 to 40 million light years away, as well as members of the great Virgo galaxy cluster , about 65 million light years away.
history
Coma Berenices is the only one of today's 88 constellations that is named after a historical person. In the Hellenistic era, the constellation was established in 245 BC. Named by the astronomer Konon von Samos and the poet Callimachos after the then pharaoh Berenike II . In the older ancient Greek mythology , no hair of Berenike is known, the corresponding stars were assigned to the constellation Leo as a tail tassel.
Berenike's hair is mentioned in several astronomical commentaries from antiquity, but is not listed as a separate constellation in the one that is decisive for the Middle Ages, the later so-called Almagest of Ptolemy (2nd century AD). When the astronomer and astrologer Luca Gaurico published the Latin translation of the Almagest by Georg von Trapezunts in Venice in 1528 , he mentioned the constellation in his commentary. Caspar Vopel then reintroduced it into astronomy by entering the name in 1532 on a hand-written celestial globe that is now in the Cologne City Museum . On another, printed globe from 1536, he drew it as a fluffy mane of hair in which a tiny female figure sits. Also in 1536 Peter Apian named the constellation on a star map. In 1551 Gerhard Mercator took it over on a celestial globe that has become famous.
The anecdote of origin
Berenike lived from about 270 to 221 BC. And was the wife of the Egyptian king Ptolemy III. When he went to the 3rd Syrian War , she promised the goddess of love Aphrodite to sacrifice her magnificent hair if her husband should return home victorious and unharmed. Ptolemy won, Berenike cut off her hair and offered it in a temple. When the head of hair was gone the next day, the court astronomer Konon declared that the gods were so pleased with the sacrifice that they had immortalized the head of hair in the sky. The poet Callimachos , who was also at court (in Alexandria ), wrote a cadastre in the form of a poem in which Berenike's hair tells what happened from heaven . The poem is preserved in the Latin translation of Catullus , the 66th of his carmina (poems) .
Meteor shower
In the constellation lies the radian of a weak meteor shower , the so-called Coma-Bereniciden . The meteors can be observed from mid-December to mid-January.
Celestial objects
Stars
| B. | F. | Names or other designations | Apparent brightness likes | Lj | Spectral class |
|---|---|---|---|---|---|
| β | 43 | Beta Comae Berenices | 4.25 | 29.78 | F9.5 V |
| α | 42 | diadem | 4.3 | 60 | F5 V |
| γ | 15th | 4.36 | 250 | K1 III | |
| 11 | 4.74 | ||||
| 36 | 4.78 | ||||
| σ | 24 | 4.78 | 250 | K2 + A9 | |
| 41 | 4.80 | ||||
| 12 | 4.81 | ||||
| 23 | 4.81 | ||||
| 37 | 4.90 | ||||
| 31 | 4.94 | ||||
| 14th | 4.95 | ||||
| 16 | 5.00 | ||||
| 6th | 5.10 | ||||
| 27 | 5.12 | ||||
| 13 | 5.18 | ||||
| 17th | 5.29 | 250 | A0 + A1 | ||
| 21st | 5.46 | ||||
| 26th | 5.46 |
The brightest star in the constellation is Beta Comae Berenices . It is a star only about 30 light-years away, which is slightly larger and more luminous than the sun.
Gamma Comae Berenices is the brightest star in the Coma star cluster 250 light-years away.
Double stars
| system | Apparent brightness likes | distance |
|---|---|---|
| α | 5.1 / 5.1 | 0.1 " |
| 2 | 5.9 / 7.4 | 3.7 " |
| 17th | 5.3 / 6.6 | 145 " |
| 24 | 5.0 / 6.6 | 20.3 " |
| 32 | 6.3 / 6.9 | 196 " |
| 35 | 5.1 / 7.2 | 1.1 " |
The second brightest star Alpha Comae Berenices, also known as the Diadem, is a double star 60 light years away . Due to the narrow angular distance, the two equally bright stars can only be observed separately with a larger telescope .
The System 24 Coma Berenices, on the other hand, can be resolved into single stars with a small telescope. A red giant and a blue-white companion star become visible.
The stars of Systems 17 and 32 Coma Berenices have such a wide angular distance with 145 and 196 arcseconds that they can be separated with prism binoculars .
The 35 Coma Berenices system is actually a triple system. The close pair AB was dissolved by Friedrich Georg Wilhelm Struve in 1929 and consists of a bright G7III main star with a magnitude of 5.1 mag and a star of the class F6V with 7.2 mag. These are currently a little more than an arc second apart.
Variable stars
| object | Apparent brightness likes | period | Type |
|---|---|---|---|
| FS | 5.3 to 6.1 | 58 days | semi-regularly changeable |
| R. | 7.1 to 14.6 | 363 days | Mira |
| FK | 8.14 to 8.33 | 2.4 days | FK Comae Berenices star |
There are more than 200 variable stars in Berenike's hair .
FS Coma Berenices changes its brightness over a period of about 58 days.
R Coma Berenices is a Mira- type variable . It changes its brightness very strongly over a period of 363 days. At the maximum brightness it is visible in binoculars, at a minimum a medium telescope is required for its observation.
FK is the namesake of a group of changeable people, the FK Comae Berenices stars . These are stars whose fluctuations in brightness are caused by extensive dark spots on the surface.
Messier and NGC objects
| Messier (M) | NGC | other | Apparent brightness likes | Type | Surname | Distance (Lj) |
|---|---|---|---|---|---|---|
| Melotte 111 | 4th | Open star cluster | Coma star cluster | 260 | ||
| 53 | 5024 | 8th | Globular clusters | 60,000 | ||
| 64 | 4826 | 8th | Galaxy | Black Eye Galaxy | 22 million | |
| 85 | 4382 | 9 | Galaxy | 65 million | ||
| 88 | 4501 | 9 | Galaxy | 65 million | ||
| 91 | 4548 | 10 | Galaxy | 65 million | ||
| 98 | 4192 | 10 | Galaxy | 65 million | ||
| 99 | 4254 | 10 | Galaxy | 65 million | ||
| 100 | 4321 | 9.5 | Galaxy | 65 million | ||
| 4147 | 10 | Globular clusters | ||||
| 4494 | 10 | Galaxy | 40 million | |||
| 4559 | 10 | Galaxy | 40 million | |||
| 4565 | 10 | Galaxy | Needle Galaxy | |||
| 4725 | 9.5 | Galaxy | 60 million | |||
| 5053 | 10 | Globular clusters |
In Berenike's hair there are a few galaxies and globular clusters that can be found with a smaller telescope . The French astronomer and comet hunter Charles Messier has added eight of them to his catalog of foggy objects ( Messier catalog ).
Objects of the Milky Way
Melotte 111 , the Coma star cluster, is a loose association of about 40 stars 260 light years away. It is the third closest open star cluster after the Bear Current and the Hyades . He delivers the most beautiful sight in bright prism binoculars , with which one has the majority of his stars in the field of view at the same time . The star cluster moves 0.02 arc seconds annually to the southwest in the direction of the constellation Sails of the Ship .
M 53 is a globular cluster about 60,000 light years away. It was discovered independently by Johann Elert Bode in 1775 and by Charles Messier in 1777 . Even in the binoculars it appears as a foggy spot.
The globular cluster NGC 5053 , discovered by Wilhelm Herschel in 1784, stands in the sky at an angular distance of only one degree . It is one of the faintest known globular clusters.
The globular cluster NGC 4147 is 85,000 light years away. A telescope is needed to observe it.
Closer galaxies
M 64 is a spiral galaxy 22 million light years away. In a larger telescope, dark clouds can be seen in the center . Since the sight is reminiscent of an eye, it is also called "Black-Eye-Galaxy" in English. Current studies show that the interstellar matter in the outer area rotates against the direction of rotation in the inner area. This indicates that the galaxy must have collided with at least one other galaxy less than a billion years ago.
NGC 4494 is an elliptical galaxy 40 million light years away.
NGC 4559 is a spiral galaxy that appears as a diffuse nebula even in binoculars. In the middle telescope, extensions of the spiral arms are perceptible.
NGC 4565 is what is known as an “edge-on” galaxy. i.e., we see them from the side. With a diameter of 13 arc minutes , it is a very extensive object and can be observed even with small telescopes. In medium-sized telescopes with an aperture of 15 cm or more, a fine dark streak of dust can be seen. Because of its elongated shape, it is also known as the “Needle Galaxy”.
NGC 4725 is a bar-type spiral. In a middle telescope, the bright core and the bar-shaped extensions become visible.
Galaxies of the Virgo Galaxy Cluster
M 85 is a lenticular galaxy and one of the northernmost members of the Virgo galaxy cluster .
M 88 is a spiral galaxy that belongs to the Markaryan chain .
M 98 is a relatively bright and extensive galaxy. Extensive spiral arms can be seen in larger telescopes.
M 100 is a spiral galaxy. With 7 arc minutes it has the largest expansion of all galaxies in the Virgo Cluster. Its diameter is about 120,000 light years. In the telescope it appears relatively poor in structure, two bright spiral arms and dust bands are visible on long-exposure photographs .
Galaxies of the Coma galaxy cluster
In the northeastern part of the constellation is the Coma galaxy cluster . Due to the huge distance of 450 million light years, however, these galaxies only achieve brightnesses of 14 mag. They are therefore only visible in larger telescopes or on long-exposure photographs.
NGC 4414 is a flaky spiral galaxy 62.3 million light years away - beyond the Virgo Galaxy Cluster and closer than the Coma Galaxy Cluster.
See also
Individual evidence
- ↑ See Elly Dekker: Caspar Vopel's Ventures in Sixteenth-Century Celestial Cartography. In: Imago Mundi. 62, 2 (2010), 161-190. Dekker quotes the statement in Gaurico: Plocamos grece latine uero cincinnus hoc est caesaries & coma uirginis Berenices fortasse crinis qui a poeta callimacho in astra relatus est: Sed cincinnum barbari tricam uocant. (Fol. 78r; Dekker, 175) Vopel's illustration is reproduced in ibid. Fig. 13.
- ↑ Stars and Space, May 2008, p. 82
