Perseus (constellation)

Constellation Perseus

Latin name	Perseus
Latin genitive	Persei
Abbreviation	By
Right ascension	1293801 ^h 29 ^m 38 ^s to 04 ^h 51 ^m 22 ^s45122
declination	2305519+ 30 ° 55 ′ 19 ″ to + 59 ° 06 ′ 17 ″2590617
surface	614.997 deg² rank 24
Completely visible	90 ° N to 31.3 ° S
Observation time for Central Europe	autumn
Number of stars brighter than 3 mag	5
Brightest star (size)	Mirfak (1.79)
Meteor streams	Perseids September Perseids
Neighboring constellations ( clockwise from north )	Cassiopeia Andromeda triangle Aries bull Carter giraffe
swell	IAU ,

The Perseus is a constellation of the northern sky. It is best seen in the autumn and winter skies and lies in the middle of the band of the Milky Way . Its northern stars look like an open star cluster to the naked eye .

In August the shooting stars of the Perseids seem to come from this constellation .

description

The constellation is said to represent the figure 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 that he is holding in his hand.

Perseus is partially circumpolar in our latitudes , i.e. i.e. visible all year round. It can be observed particularly well in autumn, when it is high above the horizon .

The Milky Way runs through the constellation, although it is not very noticeable here, as numerous dark clouds weaken the light from the stars.

In Perseus there are interesting objects to be observed, such as the open star cluster M 34 and the double star cluster h and Chi Persei .

history

Perseus is one of the 48 classical constellations described by Ptolemy .

As early as the Middle Ages , Arab astronomers observed the strange darkening of the star Algol. The name is derived from the Arabic Ras al Ghul and means head of the demon .

mythology

In Greek mythology , Perseus was the son of Zeus and Danaë . He defeated the deadly gorgon Medusa, whose gaze could turn any living being into stone, and cut off her head. Wearing winged shoes, he saved the beautiful Andromeda , who was to be sacrificed to the sea monster Ketos, chained to a rock , and got her as a wife as a reward.

Andromeda, together with her parents Cepheus and Kassiopeia , as well as the marine animal have also been immortalized in the sky as constellations near Perseus, the latter as the constellation whale (Cetus).

Artist's impression of the constellation Perseus
Photo of the constellation Perseus
Photo by Cassiopeia and Perseus 2011
The constellation of Perseus as seen with the naked eye

Celestial objects

Stars

B.	F.	Names or other designations	size	Lj	Spectral class
α	33	Mirfak (also Marfak or Algenib )	1.79 ^m	592	F5 Ib
β	26th	Algol	2.12 to 3.39 ^m	93	B8 V
ζ	44		2.9 ^m	about 1000	B1 Ib
ε	45		2.90 ^m	538	B0.5 V
γ	23		2.91 ^m	256	G8 III
δ	39		3.01	528	B5 III
ρ	25th	Gorgonea tertia	3.2 to 4.1 ^m	325	M3 III
η	15th	Miram	3.77 ^m	1331	K3 Ib
ν	41		3.77 ^m	557	F5 II
κ	27	Misam	3.79 ^m	112	K0 III
ο	38	Atik	3.84 ^m	1476	B1 III
τ	18th		3.93 ^m	248	G4 III
		MX	3.96 ^m	554	B3 Ve
ξ	46	Menkib	4.0 ^m	about 1000	O7.5
φ			4.01 ^m	717	B2 Vpe
ι			4.05 ^m	34	G0 V
θ			4.10 ^m	37	F7 V
μ			4.12 ^m	723	G0 Ib
	16		4.22 ^m	128	F2 III
	58		4.25 ^m	642	G8 II
λ			4.25 ^m	347	A0 IVn
ψ			4.32 ^m	700	B5 Ve
σ			4.36 ^m	353	K3 III
	17th		4.56 ^m	409	K5 III
b			4.60 ^m	318	A2 V
ω		Gorgonea Quarta	4.61 ^m	305	K1 III
	34		4.67 ^m	559	B3 V
	52		4.67 ^m	627	G5 II
π		Gorgonea Secunda	4.68 ^m	326	A2 Vn
k			4.77 ^m	205	K0 II-III
		V469	4.80 ^m	464	B4 IV
		HR 991	4.85 ^m	1476	K2 III
	12		4.91 ^m	81	F9 V
	54		4.93 ^m	226	G8 III
	24		4.94 ^m	350	K2 III
	32		4.96 ^m	155	A3 V
	40		4.97 ^m	924	B0.5 V
		HR 1034	4.99 ^m	570	B5 V
	4th		4.99 ^m	740	B8 III
		HR 969	5.04 ^m	834	G5 II
	31		5.05 ^m	481	B5 V
		LT	5.10 ^m	387	B9p
		V467	5.14 ^m	298	A3 V
	29		5.16 ^m	528	B3 V
		V474	5.16 ^m	2052	A2 Ia
	43		5.28 ^m	133	F5 IV
	59		5.30 ^m	271	A1 Vn
	36		5.30 ^m	119	F4 III
		HR 1011	5.32 ^m	625	B5 V
	20th		5.34 ^m	235	F4 V
		HR 1207	5.39 ^m	845	B6 V
	14th		5.43 ^m	693	G0 Ib
		HR 1330	5.46 ^m	259	A7 V
		HR 885	5.47 ^m	558	G4p
		V396	5.47 ^m	586	B8 IIIp Mn
	30th		5.49 ^m	645	B8 V
		HR 1215	5.49 ^m	971	B1.5 V

Double stars

system	Sizes	distance
ε	2.9 / 7.4 ^m	8.8 "
ζ	2.9 / 9.4 ^m	12.9 "
η	3.9 / 8.5 ^m	28 "
57	6.1 / 6.8 ^m	122 "

ε Persei is a binary star 538 light years away . Both components can be observed with a small telescope with an opening of 6 cm or more.

The binary star system ζ Persei , which is around 1000 light years away, is also easy to observe . The system belongs to an OB association called Perseus OB2 or II Perseus .

Variable stars

star	size	period	Type
β	2.12 to 3.39 ^m	2,867 days	Coverage variable
ρ	3.3 to 4.0 ^m	about 40 days	semi-regularly changeable

Algol (β Persei), the second brightest star in Perseus, changes its brightness regularly over a period of 2 days and 21 hours. The decrease in brightness is caused by a weaker companion star that passes in front of the bright main star. Algol is the namesake of a type of eclipsing star .
Algol represents the eye of the mythological Medusa.

ρ Persei is a red giant 325 light years away . Its brightness changes over a period of around 33 to 40 days.
The Latin name Gorgonea Tertia means "third of the Gorgons".

Messier and NGC objects

Messier (M)	NGC	other	size	Type	Surname
34	1039		6 ^m	Open star cluster
76	650		9.0 ^m	Planetary nebula	Small dumbbell nebula
	744		7.9 ^m	Open star cluster
	869		4.5 ^m	Open star cluster	h Persei
	884		4.5 ^m	Open star cluster	Chi Persei
	1342		6.7 ^m	Open star cluster
		Tr 2	5.9 ^m	Open star cluster
		Mel 20	1.2 ^m	Open star cluster
	957		7.6 ^m	Open star cluster
	1333		5.6 ^m	Reflection fog
	1444		6.6 ^m	Open star cluster
	1499		5.0 ^m	Gas mist	California fog
	1528		6.4 ^m	Open star cluster
	1545		6.2 ^m	Open star cluster
	1582		7.0 ^m	Open star cluster

M 34 is an open star cluster about 1,400 light years away. It offers the most beautiful sight in binoculars or in the telescope at low magnification, whereby around 100 stars become visible.

The two neighboring star clusters h and Chi Persei can be seen as foggy spots with the naked eye. They are about 7,500 light years away. Here, too, the most beautiful sight is offered in binoculars or in the telescope at low magnification, since both objects are then visible at the same time.

M 76 , a planetary nebula , is the remnant of a star about 5,000 light years away. However, it is not so easy to observe because it is quite faint.

The open star cluster Melotte 20 (α Persei group) is the conspicuous cluster of stars around the main star Mirfak, which are already visible to the naked eye. Similar to the Hyades , this group forms a movement cluster (see also Sternstrom ) and is also part of an OB association .

NGC 1499 is an emission nebula with a shape reminiscent of the US state California . It is therefore also known as the “California Nebula”. Due to its low surface brightness, the fog is only visible in long-exposure photographs .

Meteor streams

The constellation Perseus can be found in the night sky as follows: From the five times lengthened rear axle of the Big Dipper over the Pole Star to the sky W ( Cassiopeia ) and then at a right angle to the right, about halfway to Capella im Wuhrmann

In Perseus is the radiant of the Perseids meteor shower , which reaches its maximum around August 12th each year.

In addition, the weak meteor shower of the September Perseids still exists .

Web links

Commons : Constellation Perseus - Collection of images, videos and audio files

How does Perseus sound? from the alpha-Centauri television series(approx. 15 minutes). First broadcast on Mar 3. 2004.