The starry sky in childhood is simply amazing, it seems impossibly huge and infinitely beautiful. Gradually the child learns to delimit it into separate areas. The first constellation that kids remember is, as a rule, the Big Dipper. And her mysterious companion remains difficult to detect for a long time. Indeed, Ursa Minor is not the brightest constellation. In a city with its ubiquitous electric light, not all of its components are visible.
How to find the constellation Ursa Minor?
Meanwhile, in the presence of such an impressive landmark as Ursa Major, finding the constellation is quite simple. The main thing is to move at least some distance from city lighting, for example, into the depths of the park. First you need to find the Big Dipper asterism and its two outermost stars - Dubhe and Meraka. They need to be connected by a line and continued beyond Dubhe. When the length of the imaginary straight line becomes equal to five distances between Dubhe and Merak, the line will rest against the North Star, located at the very tip of the tail of the Little Dipper. The remaining luminaries rush downwards from it in an arc and reach the Small Bucket asterism.
Brightness
Ursa Minor is a small and inconspicuous constellation. It contains only a few stars that can be distinguished in urban lighting conditions: Polaris (alpha), Kohab (beta) and Ferkad (gamma). The rest are either visible only through binoculars, or can be seen in the complete absence of artificial lighting. Kokhab and Ferkad are located at the base of the Small Bucket.
Small, but smart
It would seem that Ursa Minor is an insignificant constellation, but at the same time it is constantly mentioned in scientific and fiction literature. It occupies a relatively small area, only 256 square degrees, and according to this parameter it ranks in fifty-sixth place among all eighty-eight constellations. And the fact that Ursa Minor belongs to the oldest celestial drawings, described by Ptolemy in his Almagest, is not enough for such popularity.
What's the matter? The answer lies in the main luminary, which adorns the constellation Ursa Minor. The North Star has been distinguished by people from others for many centuries. It was she, despite her dimness in comparison with such bright giants as Sirius or Vega, that ensured the glory of Ursa Minor.
Location
Polar owes its popularity to its proximity to the North Pole. This star in the constellation Ursa Minor is located at a distance of one degree from it, and in 2100, as a result of the precession of the earth's axis, it will come another half a degree closer. It seems to hover over the North Pole. Travelers of the past determined the cardinal directions by its location, and the height of the North Star above the horizon allowed travelers to understand at what geographic latitude they were located.
The North Pole is the point at which an imaginary line extending the earth's axis rests. The stars located here appear motionless to an observer from the surface of our planet. Since about 1100, the star around which the others circle has been Polaris. After 3200 it will be replaced by a new one.
physical characteristics
The North Star is of interest to scientists for other reasons. It is a triple system. Polaris A is a supergiant, two thousand times brighter than the Sun. Polar Ab is its closest companion. It is located at a distance of only eighteen and a half astronomical units from the supergiant and therefore went unnoticed for a long time. Polar B is the third companion, located at a fairly large distance from the binary system and rotating around it at a speed of one revolution every thirty years.
In addition, Polaris, or rather the main component of the system, belongs to the class of Cepheids, variable stars whose size and brightness change with a certain period. For Alpha Ursa Minor this is 3.97 days. A feature of this Cepheid is the attenuation of pulsations, as well as an increase in brightness: it increased by fifteen percent.
Guardians of the Pole
Ursa Minor is a constellation that has several other interesting objects in its composition, in addition to the North Star. For example, the so-called guardians of the pole are an asterism of two luminaries: Kohab and Ferkada. The first is an orange giant, one hundred and twenty-six light years away from our planet. It is the second largest star in the entire celestial pattern and from about 2000 BC to 500 AD it occupied the place of the North Star.
Kohab also has a small companion belonging to the star class K5. And in 2014, a planet was discovered near the star guard, supposedly 6.1 times more massive than Jupiter.
Ferkad is a white giant. It can be called a relative of the North Star, since it also belongs to the Cepheid class. The pulsation period of Ferkada is 3.43 hours. The name of the star is of Arabic origin and is derived from the designation of gamma and beta of Ursa Minor - “al-farkadan”, which exists in this language and is translated as “two calves”.
Planetary systems
Ursa Minor is a constellation in the sky rich in luminaries in which exoplanets have been discovered. In addition to the named Kohab, they include several more dimmer stars. The 11th planet Ursa Minor is located at a distance of 390 light years from Earth. This is an orange giant, living one of the last stages of its evolution. Its radius is equal to 24 solar, and its mass is only 1.8 of that of our star. In 2009, a planet was discovered circling in orbit around this star at a speed of 1 revolution every 516 days. Its mass is estimated at 10.5 Jupiterian.
Another star with a planet is designated in astronomy as HD 150706. It is separated from Earth by 100 light years. According to scientists, the planet makes one revolution around the star in almost six thousand days.
Eighth
An isolated neutron star was also discovered in the “territory” of Ursa Minor. This is the eighth such object discovered by scientists. The star has no companions, and there is no evidence of an explosion that could lead to its appearance. The seven isolated neutron stars discovered earlier are also referred to in the scientific world as the “Magnificent Seven,” so the eighth was named “Culvera” after the hero of the film “The Magnificent Seven.”
In a word, the constellation Ursa Minor, the photo of which is in the article, is not as insignificant as it seems at first glance. Its dim stars hold a lot of interesting things for the understanding mind. However, one Polar Star is enough to consider this small celestial pattern one of the most important for science.
Who doesn't know where the constellation is Ursa Minor or, he never looked at the sky in the dark. He will not be able to understand at night where is north and where is south. Polaris is less than 1° from the North Celestial Pole. And you can find it in the sky in many ways: I’m sure that during school years, parents or teachers showed where it was. And if not, it’s okay, let’s get acquainted.
Legend and history
The ancient Greek philosopher and mathematician Thales of Miletus invented and added the constellation Ursa Minor to the catalog of the starry sky of Claudius Ptolemy “Almagest”.
There are many legends associated with Ursa Minor. For example, one of them is associated with the birth of Zeus. The goddess Rhea took her newborn son to the top of Mount Ida and left her there in the care of the nymphs (Kinosura) and their mother Melissa. She did this to escape from Father Kron, who was eating his children. Having matured, Zeus ascended Melissa to heaven in the form of Ursa Major, and Kinosura as Ursa Minor. By the way, on ancient maps the North Star was called Kinosura, which translated means “dog’s tail.”
Other sources (according to Arata) in ancient times called the constellation “Little Chariot” (Ursa Major - “Great Chariot”).
The Arabs perceived Ursa Minor as horsemen. Persians - seven fruits of the date palm.
The Romans depicted it as a Spartan dog.
The Indians associated this part of the sky with a monkey.
In Ancient Babylon they even saw a leopard. And so on. Each culture and civilization tried to consider something subject to it.
Characteristics
The most interesting objects to observe in the constellation Ursa Minor
1. Spiral Galaxy NGC 6217
NGC 6217- barred spiral galaxy (). The apparent magnitude is only 11 m, and the angular dimensions of the galaxy are 3.0′ × 2.5′. At the end of the 18th century (in 1797) it was discovered by the English astronomer William Herschel.
Unfortunately, to distinguish the “arms” of the galaxy you will need a powerful telescope with an aperture of 200 millimeters or more. I found a nice amateur photo of the galaxy on the Internet. NGC 6217:
In fact, if you look more closely, you can clearly distinguish spiral irregularities and a very saturated galactic core. The closest bright star to the galaxy is ζUMi(4.3 m), but it is unlikely that you will lay the route exactly from it. In the immediate vicinity of the desired deep-sky object there is a characteristic small cluster of stars, visible even in a finder - they will serve as an excellent landmark.
2. Polaris (α UMi)
First of all, Polaris (α UMI) is a star that consists of a dwarf, spectral class F. The brightness of the system is 2.02 m. The distance to the Sun is 320 light years, somewhere you can find the number 435.
Amateur telescopes will not be able to discern the second component of the star. It is located too close, plus the main component is bright. Cepheid has a pulsation period of slightly more than 4 days, while the brightness amplitude changes by 0.12 m.
The polar star is not difficult to find: one option is to mark five distances in the sky between the two stars of the bucket (Dubhe and Merak) of the Big Dipper in the direction opposite to the bottom of the bucket. If you haven’t succeeded before, be sure to practice and remember.
> Ursa Minor
| An object | Designation | Meaning of the name | Object type | Magnitude |
| 1 | Kinosura (North Star) | "Polar Star" | Multiple star system | 1.98 |
| 2 | Kohab (Beta Ursa Minor) | "Star of the North" | Orange giant | 2.08 |
| 3 | Ferkad | "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 (Delta Ursa Minor) | "Star" | Blue-white subgiant | 4.35 |
| 7 | This Ursa Minor | "Bright Calf" | White-yellow dwarf | 4.95 |
How to find constellation Ursa Minor in the northern hemisphere: description with photos, diagram and map of the starry sky, facts, myth, asterism Small Dipper and Polar Star.
Ursa Minor - constellation, which 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 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 from Miletus (lived between 625 and 545 BC). He was called one of the 7 Greek sages. But there is an option that he simply discovered it to the Greeks, and it was also found by the Phoenicians, who used the ladle for navigation. The Greeks even called it Phoenician until it became the Little Dipper (previously also called the Tail of the Dog).
Facts, position and map of the constellation Ursa Minor
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 in latitudes from +90° to -10°. Adjacent to , and .
| Ursa Minor | |
|---|---|
| Lat. Name | Ursa Minor |
| Reduction | UMi |
| Symbol | Teddy Bear |
| Right ascension | from 0 h 00 m to 24 h 00 m |
| Declension | from +66° to +90° |
| Square | 256 sq. degrees (56th place) |
| Brightest stars (value< 3 m ) |
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| Meteor showers |
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| Neighboring constellations |
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| The constellation is visible at latitudes from +90° to −0°. The best time to observe is all year round. |
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Contains a star with a planet and not a single Messier object. The brightest star is Polaris (Alpha Ursa Minor), whose apparent visual magnitude reaches 1.97. There is a meteor shower - the Ursids. Included in the Ursa Major group along with, and. Consider the diagram of the constellation Ursa Minor on a star chart.
Myth about the constellation Ursa Minor
There are two different stories about Ursa Minor. The first one is about Ida. This is the nymph who raised Zeus when he was small on the island of Crete. His mother Rhea had to hide him from Kronos (father), who killed all his children because of the prophecy. As soon as Zeus was born, she placed a stone in his place and deceived her husband. The prophecy came true. The son overthrew his father and freed his brothers and sisters, who became Olympian gods.
Another story tells about Arcas. This is the son of Zeus and Callisto (nymph). She was devoted to Artemis and refused relationships with men. But she could not resist Zeus. When Hera found out about the betrayal, she turned the girl into a bear in a rage. Callisto had to wander through the forest for 15 years until she saw the adult Arkas. He got scared and took out his spear. Zeus made it in time and sent a whirlwind that lifted both of them to the heavens. Callisto became Ursa Major, and Arcas became Ursa Minor. But most often he is still attributed to Bootes.
There is an even more ancient myth, according to which 7 stars reflected the Hesperides - the daughters of Atlas, guarding the apples in the garden of Hera.
Asterism
The Small Dipper is created by the stars: Polaris, Yildun, Epsilon, Eta, Zeta, Gamma and Beta.
The main stars of the constellation Ursa Minor
Explore carefully the bright stars of the Ursa Minor constellation of the northern hemisphere with a detailed description, photo and characteristics.
polar 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 it, you need to follow Dubhe and Merak (the two brightest ones at the end of the Ursa Major asterism).
Represented by the 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. Its mass is 6 times greater than that of the sun. In 1780, William Herschel found B to be a main sequence star (F3) and Ab to be a dwarf in a very close orbit.
Polaris is a population variable of I Cephei. In 1911, its variability was confirmed by the Danish astronomer Einar Hertzsprung. At the time of Ptolemy's observations, it was a 3rd magnitude star, but today it is 2nd magnitude. Because of its brightness and proximity to the pole, it is an essential tool in celestial navigation.
Kohab(Beta Ursa Minor) is a giant (K4 III) with a visual magnitude of 2.08 (the brightest in the bowl) and a distance of 130.9 light years. Beta and Gamma are sometimes called the Guardians of the Pole because they appear to orbit the North Star.
From 1500 BC to 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 massive.
The traditional name comes from the Arabic al-kawkab - “star” and is an abbreviation for al-kawkab al-šamāliyy - “north 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 the rotation speed reaches 180 km/s. The radius is 15 times larger than the sun and 1,100 times brighter.
It is an envelope star that has a disk of gas at its equator, which causes changes in magnitude.
The name means "calf" in Arabic.
Yildun(Delta Ursa Minor) is a main sequence (A1V) white dwarf with a visual magnitude of 4.35 and a distance of 183 light years. The traditional name is translated from Turkish as “star”.
Zeta Ursa Minor– 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 greater than the solar mass, 200 times brighter. Surface temperature - 8700 K. This is a suspected Delta Scuti variable.
From Arabic aḫfa al-farqadayn means "leading two calves."
This Ursa Minor– 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 the use of technology.
Translated from Arabic as “brighter than two calves.”
Epsilon Ursa Minor- a triple star system located 347 light years away. Shown is A, a yellow G-type giant (eclipsing spectroscopic double star) and B, an 11th magnitude star at a distance of 77 arcseconds.
Epsilon A is also a Canes Venatici RS variable. The brightness of the binary system changes due to the fact that one object periodically covers the second. The overall brightness varies from magnitude 4.19 to 4.23 with a period of 39.48 days.
Celestial objects of the constellation Ursa Minor
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. This is a satellite galaxy of the Milky Way. Most stars are old and there is virtually no visible star formation.
Found in 1954. Information provided by the Hubble Space Telescope in 1999 confirmed that 11 billion years ago the galaxy underwent a formation period that lasted 2 billion years.
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 independent searching, a star map is suitable.
