Mug (constellation)
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Constellation mug |
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|---|---|
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| Latin name | Crater |
| Latin genitive | Crateris |
| Abbreviation | Crt |
| Right ascension | 10 h 51 m 06 s to 11 h 56 m 24 s |
| declination | −25 ° 11 ′ 45 ″ to −6 ° 39 ′ 44 ″ |
| surface | 282,398 deg² rank 53 |
| Completely visible | 65.0 ° N to 90 ° S |
| Observation time for Central Europe | November to May |
| Number of stars brighter than 3 mag | 0 |
| Brightest star (size) | Delta Crateris (3.56) |
| Meteor streams |
no |
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Neighboring constellations ( clockwise from north ) |
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| swell | IAU , |
 From the Uranometria by Johann Bayer |
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The cup ( Latin crater ) is a constellation south of the celestial equator .
description
The cup is a small constellation north of the water snake (Hydra), with which it also has a close mythological relationship. It consists of an inconspicuous group of stars around the 4th magnitude .
The best time for observations are March to May.
history
The cup belongs to the 48 constellations of ancient astronomy , which were already mentioned by Ptolemy .
At the beginning of the 17th century one saw the “Cup of the Passions of Christ” in the constellation. However, this designation has not caught on.
mythology
In Greek mythology , the cup is associated with the constellations raven (Corvus) and water snake:
Apollo sent a raven to make an offering to his father Zeus so that he could get water from a spring. The raven grabbed the mug and set off. On the way, however, he saw not quite ripe figs on a fig tree, which he absolutely wanted to taste. So he waited a few days for the figs to ripen and only then did he finish his job. To apologize for being late, he grabbed a water snake and claimed it had blocked the way to the spring.
But Apollo saw through the lie and punished the raven by the fact that he could no longer drink at the time the figs were ripe and sent him, together with the cup and the water snake, as a warning to heaven.
According to another tradition, King Demophon of Elaios sacrificed a noble daughter of his city every year to ward off epidemics. The victim was determined by lot, although Demophon always excluded his own daughter. When one of the nobles by the name of Matusios protested against this and demanded that the king's daughter also take part in the raffle, Demophon had his daughter sacrificed without further ado. Matusios took bloody vengeance, killed the king's daughter and had Demophon served wine that was mixed with his daughter's blood. Matusios was executed for this outrage, and the cup was moved to heaven as a warning.
Celestial objects
Stars
| B. | F. | Names or other designations | Vmag (mag) | Lj | Spectral class |
|---|---|---|---|---|---|
| δ | 12 | Labr | 3.57 | 90 | K0 III |
| α | 7th | Alkes | 4.08 | about 160 | K1 III |
| γ | 15th | 4.08 | 84 | A5 V | |
| β | 11 | Al Sharasif | 4.46 | 200 | A2 III |
| θ | 21st | 4.46 | |||
| ζ | 27 | 4.71 | |||
| ε | 14th | 4.81 | |||
| 17th | 4.93 | ||||
| λ | 13 | 5.08 | |||
| η | 30th | 5.17 | |||
| 31 | 5.28 | ||||
| ι | 24 | 5.49 | |||
| κ | 16 | 5.93 | |||
| ψ | 6.11 |
Delta Crateris , the brightest star in the cup, is a yellowish shining star of the spectral class K0 90 light years away .
The second brightest star, Alkes , is around 160 light years away. His proper name is of old Arabic origin and means "jug".
Double stars
| system | Vmag (mag) | distance |
|---|---|---|
| γ | 4.08 / 9.6 | 52 " |
| 17th | 4.93 / 5.64 |
γ Crateris is a binary star system 84 light years away . A medium-sized telescope is required to resolve the system into single stars .
Variable stars
| object | Vmag (mag) | period | Type |
|---|---|---|---|
| R. | 9.8 to 11.2 | 160 days | irregularly variable |
| SV | 6.14 |
R Crateris is a semi-regularly variable star belonging to the spectral class M7. Its brightness fluctuates from 9.8 to 11.2 m within about 160 days . A medium telescope is required to observe it.
SV Crateris is also called Gliese 425 or Abbot's star . At a distance of 44 light years it belongs to the closer environment of the sun .
NGC objects
| NGC | other | Vmag (mag) | Type | Surname |
|---|---|---|---|---|
| 3511 | 12 | Galaxy | ||
| 3887 | 11 | Galaxy | ||
| 3981 | 12 | Galaxy |
There are three galaxies in the cup that can already be observed with medium-sized telescopes.
NGC 3511 is an SBbc-type spiral galaxy that we see from the side. It belongs to the galaxy cluster Abell 1060 . Its extent in the sky is 4 × 1 arc minutes .
NGC 3887 is a bar-shaped spiral galaxy of type SBc with a diameter of 3.5 minutes of arc.
NGC 3981 is an SBbc-type galaxy. Two distinct spiral arms are visible in the larger telescope. The galaxy was discovered by Wilhelm Herschel in 1785 .
See also
Web links
Individual evidence
- ↑ a b Constellations Becher - Latin Crater, Crateris (Gen.), and Rabe - Latin Corvus Corvi. In: Günther Bendt, Baader Planetarium GmbH, D-82291 Mammendorf. 2019, accessed July 19, 2019 .
- ^ Sushma V. Mallik: Lithium abundance and mass. In: Astronomy and Astrophysics. 352, December 1999, pp. 495-507, bibcode : 1999A & A ... 352..495M .
- ↑ cup (crater). In: Sternfreunde Münster eV 2017, accessed on July 19, 2019 .