CapricornusCapricornus
Abbreviation:
X. sign of zodiac
Particulars:
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.
