Constellations > Ursa Minor

Ursa Minor is a constellation that is located in the northern sky and from Latin “Ursa Minor” means “lesser bear”.

The constellation Ursa Minor appeared in the sky in the second century thanks to Ptolemy. It is easy to find by its famous asterism or its location at the North Celestial Pole. At the end of the bucket handle, you can see the North Star.

Although Ptolemy wrote it down, the authorship of the creation is given to Thales of Miletus (lived between 625 and 545 BC). He was called one of the 7 Greek sages. But there is an option that he simply opened it to the Greeks, and the Phoenicians also found it, using a bucket for navigation. The Greeks even called it Phoenician until it became Ursa Minor (previously also called Dog’s Tail).

Constellation Ursa Minor

An object Designation Meaning of the name Object type Magnitude
1 Kinosura (North Star) “Polar Star” Multiple star system 1.98
2 Cohab (Beta Ursa Minor) “Star of the North” Orange giant 2.08
3 Fercad “Two calves” White giant 3.05
4 Epsilon Ursa Minor No Binary star system 4.21
5 Zeta Ursa Minor No White dwarf 4.32
6 Yildun (Ursa Minor Delta) “Star” Blue-white subgiant 4.35
7 This Ursa Minor “Bright Calf” White and yellow dwarf 4.95

Facts, position and map

With an area of ​​256 square degrees, the constellation Ursa Minor is the 56th largest constellation. Covers the third quadrant in the northern hemisphere (NQ3). It can be found at latitudes between + 90 ° and -10 °. Adjacent to Chameleon, Cepheus and Dragon.

Ursa Minor
Lat. title Ursa Minor
Reduction UMi
Symbol Teddy bear
Right ascension from 0h 00m up to 24h 00m
Declination from + 66 ° to + 90 °
Square 256 sq. degrees
(56th place)
The brightest stars
(value <3m)
  • North Star (α UMi) – 2.02m
  • Cohab (β UMi) – 2.08m
Meteor showers
  • Ursids
Nearby constellations
  • The Dragon
  • Giraffe
  • Cepheus
The constellation is visible in latitudes from + 90 ° to −0 °.
The best time to watch is all year round.

Accommodates a star with a planet and no Messier objects. The brightest star is Polaris (Alpha Ursa Minor), whose apparent visual magnitude reaches 1.97. There is a meteor shower – Ursids. Included in the Ursa Major group along with Veronica’s Hair, Giraffe, Dragon, Little Lion, Ursa Major, Lynx, Northern Crown, Hounds and Bootes. Consider the constellation diagram of the Ursa Minor on the map of the starry sky.

Constellation Ursa Minor

Myth

There are two different stories about Ursa Minor. The first is about Ida. This is the nymph who raised Zeus when he was little on the island of Crete. Rhea’s native matter had to hide him from Kronos (father), who, because of the prophecy, killed all his children. As soon as Zeus was born, she put a stone in his place and deceived her husband. The prophecy has come true. The son overthrew his father and freed his brothers and sisters, who became Olympic gods.

Another story tells about Arkas. This is the son of Zeus and Callisto (nymph). She was loyal to Artemis and gave up relationships with men. But she could not resist Zeus. When Hera found out about the betrayal, in a rage she turned the girl into a bear. Callisto had to wander through the forest for 15 years until she saw an adult Arkas. He got scared and took out his spear. Zeus made it in time and sent a whirlwind that lifted both to heaven. Callisto became the Ursa Major, and Arkas became the Ursa Minor. But most often he is still attributed to Bootes.

There is an even more ancient myth, according to which 7 stars depicted the Hesperides – the daughters of Atlas, guarding the apples in Hera’s garden.

Asterism

The Small Dipper is created by the stars: Polaris, Yildun, Epsilon, Eta, Zeta, Gamma and Beta.

Trinary star system of the North Star.

Trinary star system of the North Star.

Main stars

Explore the bright stars of the constellation Ursa Minor in the northern hemisphere with detailed descriptions, photos and characteristics.

The North Star (Alpha Ursa Minor) is a multiple star (F7: Ib-II) with an apparent magnitude of 1.985 and a distance of 434 light years. It is the closest bright star to the North Celestial Pole since the Middle Ages and the brightest in Ursa Minor.

To find her, you need to follow Dubhe and Merak (the two brightest at the end of the Ursa Major asterism).

Represented by bright object A, two smaller companion stars B and Ab, and two distant stars C and D.

The brightest body is a giant (II) or supergiant (Ib) with spectral class F8. The mass is 6 times that of the sun. In 1780, William Herschel found B a main sequence star (F3) and Ab a dwarf in a very close orbit.

Polaris is a population variable of I Cepheus. In 1911, its variability was confirmed by the Danish astronomer Einar Hertzsprung. At the time of Ptolemy’s observations, it was a 3-magnitude star, but today it is 2. Due to its brightness and proximity to the pole, it is an essential tool in astronomical navigation.

Ursa Major and Ursa Minor

Ursa Major and Ursa Minor

Kohab (Beta Ursa Minor) is a giant (K4 III) with a visual magnitude of 2.08 (brightest in the bowl) and a distance of 130.9 light years. Beta and Gamma are sometimes referred to as the Pole Guardians because they seem to orbit the North Star.

From 1500 BC before 500 AD they were twin stars, being the closest bright stars to the north celestial pole. Kohab is 130 times brighter than the Sun and 2.2 times more in mass.

The traditional name comes from the Arabic al-kawkab – “star” and is short for al-kawkab al-šamāliyy – “northern star”.

Ferkad (Gamma Ursa Minor) is a type A star with an apparent magnitude of 3.05 and a distance of 487 light years. It is classified as A3 lab and has a rotational speed of 180 km / s. Its radius is 15 times greater than that of the Sun and 1,100 times brighter.

It is an envelope star with a disk of gas at the equator, resulting in changes in magnitude.

The name from Arabic means “calf”.

Yildun (Ursa Minor Delta) is a main sequence white dwarf (A1V) with a visual magnitude of 4.35 and a distance of 183 light years. The traditional name from Turkish is translated as “star”.

Zeta Ursa Minor is a main sequence dwarf (A3Vn) with a visual magnitude of 4.32 and a distance of 380 light years. In fact, it is on the verge of becoming a giant: 3.4 times the solar mass, 200 times brighter. The surface temperature is 8700K. This is a suspected Delta Shield variable.

From Arabic aḫfa al-farqadayn means “leading two calves.”

This Ursa Minor is a yellow-white main sequence dwarf (F5 V) with a visual magnitude of 4.95 and a distance of 97.3 light years. It can be found without using any technique.

It translates from Arabic as “brighter than two calves.”

Epsilon Ursa Minor is a triple star system 347 light years distant. A – a yellow giant of the G-type (an eclipsing spectroscopic binary) and B – an 11th-magnitude star with a distance of 77 arc seconds are represented.

Epsilon A is also a Hound RS type variable. The brightness of the binary system changes due to the fact that one object periodically covers the second. The total brightness changes from 4.19 to 4.23 with a period of 39.48 days.

Celestial objects

Ursa Minor (PGC 54074, UGC 9749) is a dwarf elliptical galaxy with an apparent magnitude of 11.9 and a distance of 200,000 light years. It is a satellite galaxy of the Milky Way. Most of the stars are old and virtually no star formation is noticeable.

Found in 1954. Information provided by the Hubble Space Telescope in 1999 confirmed that the galaxy had a formation period of 2 billion years 11 billion years ago.

You have the opportunity to study the constellation Ursa Minor in the northern hemisphere more carefully if you use not only our photos, but 3D models and an online telescope. For an independent search, a map of the starry sky is suitable.


Constellations of the summer sky
June Bootes Compass Libra Wolf Ursa Minor
July Bird of Paradise Altar Crown of the North Dragon Hercules Square Ophiuchus Scorpio Serpent Southern Triangle
August Crown South Lyra Sagittarius Shield Telescope
Constellations

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