[Pic]

Abbreviation:

Cap

English name:

Sea Goat

Coordinates

see Stellar data

X. sign of zodiac

Particulars:

• Double stars alpha Cap, beta Cap
• Variable star delta Cap
• Globular cluster M 30
• Meteor Showers: Alpha Capricornids, Chi Capricornids, Sigma Capricornids, Tau Capricornids, Capricorniden-Sagittariids

General:

A constellation of the southern sky. Capricorn streches from RA=20h 10m to RA=22h and from DECL=-9 degrees to DECL=-27 degrees (roughly spoken). It belongs to the Zodiac Constellation Family.
The sun passes through Capricorn from late January to mid-February. In ancient times the sun was in this constellation at the winter solstice. Due to the precession of the Earth axis, the sun is now in the neighbouring constellation Sagittarius at this time of the year. The latitude on Earth on which Capricorn appears overhead of an observer is still known as the Tropic of Capricorn.
The other constellations next to Capricornus are Microscopium and Piscis Austrinus to the south, Aquarius to the east and north and Aquila at the north-western border.

Stars and other objects

The double alpha Cap, known as Algedi (arabic: 'goat' or 'ibex'), consists of a G3 supergiant of 4.24 mag and a G8 giant of 3.57 mag brightness. They can be spotted without optical help. The two stars are not physically attached; they only seem to be double. Viewed through a small telescopes it is revealed that both stars are themselves double: alpha 1 Cap has an 9th mag companion and alpha 2 Cap shows up with an 11th mag companion.
A good object for binoculars of small scopes is beta Cap, called Dabih. The F8 main sequence star of 3rd mag has a 6th mag companion (spectral type A0).
The globular cluster M 30 (NGC 7099) can easily be seen in small scopes. Yet is it difficult to split individual stars of this 7th mag star cluster.
Although this region of the sky has not too many objects for observations there are a couple of meteor showers associated with this constellation:
The meteor shower Alpha Capricornids has a quite long duration. It takes place from 15th of July to 11th of September. The maximum of the shower activity occurs around the 1st of August with 6-14 meteors per hour. The meteors are known to be slow and some of them can reach brightnesses up to 2nd mag.
The Chi Capricornids belong to the daylight meteor showers. The shower is active from 29th of January to 28th of February reaching the maximum on 13th of February.
Another daylight shower are the Capricornids-Sagittariids. This shower extends from 13th of January to the 28th of February. Between the 30th of January and the 3rd of February this stream reaches its maximum.
The Sigma Capricornids and the Tau Capricornids belong to the minor meteor showers. See Gary Kronk's database of meteor showers for details.

Mythological Background:

According to Eratosthenes of Cyrene (284 - 202 B.C.; see his Catasterismi) this constellation represents the son of Aegipan. He lived with Zeus on the Mountain Ida on Crete. He accompanied Zeus against the Titans. He found the horns of the sea, Conchas, and tought his companions how to use them. When they faced their enenmies, the Titans, the blew on these horns instead of using the trumpets. Hearing this the Titans flew. To honour him Zeus placed him under the stars in a way that he was part goat part fish, as a sign that he found the horn of the sea.
Hygenus (lived in the times of Augustus) tells us in his poeticum astronomicum II.c.28 a different story. He is of the opinion that this constellation represents Pan. When Pan fled from Thyphaon to Egypt, he changed himself to this animal and hide in the river Nile. Zeus liked this idea so much that he made a place on the sky to remind in it.