Perseus (constellation)
- Perseids
- September Perseids
- Cassiopeia
- Andromeda
- Triangle
- Aries
- Taurus
- Carter
- Giraffe
The Perseus is a constellation of the northern sky. It is best to see the autumn and winter sky and is located in the band of the Milky Way.
Description
The constellation is supposed to represent the shape of the Greek hero Perseus, who defeated the deadly Medusa. The stars Mirfak, δ, ε and ζ form the body and a leg of Perseus. The star Algol represents the severed head of Medusa, which he holds in his hand.
Perseus is partially circumpolar, ie, visible throughout the year in our latitudes. Particularly, it can be observed in the fall, because he is high above the horizon.
Through the constellation the Milky Way, but that is not very noticeable here, as many dark clouds attenuate the light of the stars draws.
In Perseus there are interesting objects to observe how the open cluster M 34 and the double cluster h and chi Persei.
History
Perseus is one of the 48 classical constellations described by Ptolemy.
In the Middle Ages Arabic astronomers had observed the peculiar darkening of the star Algol. The name derives from the Arabic Ras al Ghul, meaning " Head of the Demon ".
Mythology
In Greek mythology, Perseus was the son of Zeus and Danae. He defeated the deadly Gorgon Medusa, whose gaze could turn every living thing into stone and cut her head off. Clothed with wings on his shoes, he rescued the beautiful Andromeda, which should be chained to a rock sacrificed to the sea monster Keto, and got it as a reward for his wife.
Andromeda, they and their parents Cepheus and Cassiopeia and the Meeresuntier have also been immortalized as constellations near the Perseus in the sky, the latter as a constellation Cetus ( Cetus ).
Celestial objects
Stars
Double stars
ε Persei is 538 light years distant binary star. Even with a small telescope from 6 cm opening both components can be observed.
Also easy to observe the binary star system about 1,000 light years distant ζ Persei. The system belongs to an OB association, which is referred to as Perseus OB2 or II Perseus.
Variable Stars
Algol ( β Persei ), the second brightest star in Perseus, changes its brightness regularly over a period of 2 days and 21 hours. The drop in brightness is caused by a fainter companion star, which passes in front of the bright primary star. Algol is the namesake of one type of eclipsing binary stars. Algol represents the eye of the mythological Medusa.
ρ Persei is 325 light years distant red giant. Its brightness changes over a period of about 33 to 40 days. The Latin name Gorgonea Tertia means " third of the Gorgons ."
Messier and NGC objects
M 34 is an open cluster in about 1,400 light-years away. The most beautiful sight he offers in binoculars or telescope at low magnification, with about 100 stars are visible.
The two neighboring clusters h and Chi Persei can already be seen with the naked eye as a hazy spot. You are at about 7,500 light- years away. Even here there is the most beautiful sight in binoculars or telescope at low magnification, since both objects are simultaneously visible then.
M 76, a planning -driven fog, is the remnant of a star about 5,000 light-years away. He is not as easy to observe, since it is quite faint.
The open cluster Melotte 20 ( α Persei group) is the conspicuous accumulation of already visible with the naked eye stars around the main star Mirfak. Much like the Hyades, this group forms a pile movement (see also stellar stream ) and is also part of an OB association.
NGC 1499 is an emission nebula, which is shaped like the U.S. state of California. It is therefore also referred to as the " California Nebula ". Because of its low surface brightness of the nebula is only visible on long-exposure photographs.
Meteor streams
In Perseus is the radiant of the meteor shower Perseids, which reaches its maximum around the 12th of August each year.
In addition, there is a weak meteor shower of the September Perseids.