Where is the little bear? Ursa Minor - description and photo of the constellation. Here's a little instruction

If you look back centuries, then among many asterisks, it occupies a rather important position. All facts indicate that ancient navigation relied on it. Although the Phoenicians sometimes used the Big Dipper for orientation, despite its great brightness, it gave significant inaccuracies in determining the path.

How to find Ursa Minor from Ursa Major?

Obviously, most of you will find Ursa Major with ease. She is quite expressive and bright. Knowing that both constellations are nearby, it will undoubtedly become clear how to find Ursa Minor from Ursa Major. To do this, you will need to mentally connect the last two stars of the Big Dipper: from Merak (β Ursa Major) to Dubha (α Ursa Major)), continuing this line upward to a distance 5 times greater than the distance between them. This is how you will discover Alpha (the North Star) of the Ursa Minor constellation.

Before wondering how to find the constellation Ursa Minor, knowing only the location of Polaris, you need to understand what figure the luminaries form, and how the asterisk is located relative to the Big Dipper.

For a complete understanding: according to their names, they are quite similar and resemble a ladle in shape. As for the location, Ursa Minor is practically in an inverted position relative to the Big Dipper.

Knowledge is power

Study the star map before starting your search, this will make it easier for you to find the asterisk. Subsequently, you will be convinced of the ease of detection of the desired star group. And if someone asks you how to find Ursa Minor from Ursa Major, you, with full knowledge of the matter, can clearly explain how to find it.

Well, now we know how to find the constellation Ursa Minor. Let's talk about the North Star, thanks to which travelers and sailors of the past made a long and difficult journey. Although it is not in the night sky, it is located closest to the northern point of the world, with an error of less than 1°. After only 145 years, the position error will exceed one degree.

Only after 3200 will the star closest to the northern point of the world become Alderamin (alpha Cephei).

"Twists" the bear by the tail on the earth's axis

The North Star does not change its position, despite the Earth's daily rotation around its own axis and annual movement in orbit around the Sun. The brightness of the guiding star is not constant and changes intensity every 4 days, within 2.02 ± 2%. Previously, the luminosity amplitude was higher, but today it has stabilized. The overall brightness of the North Star is constantly growing and has increased by almost 15% over the past hundred years.

The nature of the pulsation is related to the properties of the star; this is exactly how Cepheids behave. Guiding Star is one of the brightest Cepheids in the night sky.
Ursa Minor occupies an area of ​​about 255.9 square degrees in the sky. Its closest neighbors are the Dragon and Cepheus.

In the asterisk, as already mentioned, the North Pole of the World is located - where all objects revolve around it. First mentioned in historical sources was made by the Greek astrologer Ptolemy in the 2nd century.

Ursa Minor and its stars

The Little Dipper constellation includes seven bright objects. Of all the luminaries of Ursa Minor, only the three brightest are clearly visible. These are Ferhad and Kohab, forming the wall of the Bucket, and crowning the handle of the constellation Polaris. The last two stars are located above the tail of Ursa Major.

The Little Dipper is somewhat different from other constellations. It does not change its location in the sky, like Ursa Major and most other asterisks, which are seasonal. They can be observed in certain seasons, and they are mobile in the sky throughout the year. Ursa Minor also changes its location, rotating around its Alpha.

"Alpha and Omega" constellation Ursa Minor in the northern hemisphere

Alpha (Pole Star) Ursa Minor is located at a distance from Earth of 431 with an apparent magnitude of 2.02. As it became known, this is not one, but three stars united in unified system. The brightest among them is almost 2 thousand times greater than the brightness of the Sun. The second luminary Ursa Minor has a mass equal to 1.39 solar.

It can be observed through a small telescope. The third Alpha star is 1.25 times more massive than our Sun and is located quite close to the first. With the help of the Hubble telescope, it became possible to view it as a separate star.

Kohab is a giant orange color, translated from Arabic as “Star of the North”. The second brightest star, also known as beta, is in the constellation Little Dipper with 2.8 and is 126 light years away from Earth.

Ferhad is the gamma of Ursa Minor, with a magnitude of 3.6, the distance to it is 480 light years. This object is considered a hot giant with a temperature of 8600 K and belongs to the variable type of stars.

Delta Small Dipper, or Yildun, is a dwarf white, which is located 183 light years away.

Zeta is another dwarf, white in color and located 380 light years from Earth. The intensity of its glow is 200 times higher than that of the Sun. It is on the way to forming a giant star.

The North Star will not let you down

You may not be able to remember it all, but your knowledge has become more extensive. And if suddenly you get lost in the forest and there is no mobile connection, try to remember how to find Ursa Minor by Ursa Major. You will certainly find the North Star and find your bearings in which direction north is.

The sky is full of secrets and unknown mysteries

Even without a telescope, just looking at the night lights, you will see how diverse our large Universe is.

The constellation Ursa Minor is just a small visible part of it. The boundaries and dimensions of the Universe visible to us today have been determined. These are truly gigantic magnitudes, its extent is about 14 billion light years.

But is the Universe like this in reality? This thought excites the minds of great scientists. They build hypotheses, research, argue and try to understand whether this is true? Some experts express the opinion that the Universe is infinite, others - that the Multiverse exists.

And it may well turn out that one of them contains the same planet, country and copy of you. Everything is possible, science constantly pushes back the veil of the unknown and hidden from our view, invariably proving: what seems science-fiction today comes true tomorrow.

Learning to find Ursa Minor, Cassiopeia and Dragon

Prepared by O. Malakhov

So, let's begin our acquaintance with the starry sky. Today we will get acquainted with the four constellations of the Northern sky: Big Dipper, Ursa Minor (with the famous North Star), Dragon and Cassiopeia. All these constellations, due to their proximity to the North Pole of the world at European territory former USSR are non-setting. Those. they can be found in the starry sky on any day and at any time. The first steps should begin with the well-known “bucket” of the Big Dipper. Did you find it in the sky? If not, then to find it, remember that on summer evenings the “bucket” is located in the northwest, in autumn – in the north, in winter – in the northeast, in spring – directly overhead. Now pay attention to the two outermost stars of this “bucket” (see figure).

If you mentally draw a straight line through these two stars, then the first star, the brightness of which is comparable to the brightness of the stars in the “bucket” of the Big Dipper, will be the North Star, which belongs to the constellation Ursa Minor. Using the map presented in the figure, try to find the remaining stars of this constellation. If you are observing in an urban environment, then it will be difficult to see the stars of the “small dipper” (this is how the constellation Ursa Minor is unofficially called): they are not as bright as the stars of the “big dipper”, i.e. Ursa Major. For this it is better to have binoculars on hand. When you see the constellation Ursa Minor, you can try to find the constellation Cassiopeia. I don’t know about you, but for me it was initially associated with another “bucket”. It’s more like a “coffee pot.” So, look at the second-from-last star of the “bucket handle” of Ursa Major. This is the star next to which there is an asterisk barely visible to the naked eye. The bright star is named Mizar, and the one next to it is Alcor (here is the range of iconic Soviet telescopes for astronomy enthusiasts produced by the Novosibirsk Instrument-Making Plant (Refinery)). They say that if translated from Arabic, Mizar is a horse, and Alcor is a rider. Being familiar with Arabic I can’t confirm this, but we’ll trust the books.

So, Mizar has been found. Now draw a mental line from Mizar through the North Star and further to approximately the same distance. And you will probably see a rather bright constellation in the form Latin letter W (see picture). This is Cassiopeia. It still looks a bit like a “coffee pot,” doesn’t it?

After Cassiopeia, we try to find the constellation Draco. As can be seen from the picture at the top of the page, it seems to extend between the “buckets” of Ursa Major and Ursa Minor, going further towards Cepheus, Lyra, Hercules and Cygnus. We will talk about these constellations a little later, and, having gained basic experience in orienting in the starry sky, try to find the entire Draco constellation using the mentioned picture.

Now you should be able to easily find the constellations Ursa Major and Ursa Minor, Cassiopeia, and Draco in the sky.

Questions:
1. In what area of ​​the sky was the constellation Cassiopeia located during your observations?
2. In what area of ​​the sky was the “bucket” of the Big Dipper located?
3. Were you able to see Alcor with the naked eye?

(lat. Ursa Minor) is a circumpolar constellation in the northern hemisphere of the sky. It occupies an area of ​​255.9 square degrees in the sky and contains 40 stars visible to the naked eye.

Ursa Minor currently houses the North Celestial Pole, at a distance of about 1° from the North Star. The constellation was probably identified by the Phoenicians as useful for navigation.

click on the image to enlarge it

Stars

The brightest stars of the constellation:

• Polaris (αUMi). Magnitude 2.02m.
• Kohab (βUMi). Apparent magnitude 2.08m. In the period from approximately 2000 BC. e. to 500 AD e. Kohab was the bright star closest to the North Pole and played the role of the polar star, which is reflected in its Arabic name Kohab el Shemali(Star of the North).
• Ferkad (γ UMi). Magnitude 3.05m.

Asterisms

Asterism Small Bucket forms a characteristic, memorable figure in the sky. Includes seven stars - α (Polar), β (Kokhab), γ (Ferkad), δ, ε, ζ and η Ursa Minor. The Small Dipper resembles the shape of the Big Dipper asterism, located nearby in the constellation Ursa Major.

The pair of extreme stars of the Bucket (Kokhab and Ferkad) represent an asterism Guardians of the Pole.

Searching the sky

Constellation visible all year round. To find the North Star (α Ursa Minor), you need to mentally extend the segment between Merak (β Ursa Major) and Dubhe (α Ursa Major) to a distance 5 times its length.

Story

According to Gigin in ancient astronomy this constellation was introduced by Thales of Miletus, included in the catalog starry sky"Almagest".

The legend about the birth of Zeus is also associated with Ursa Minor. To save her son from father Cronus, who was eating his children, the goddess Rhea took Zeus to the top of Mount Ida, in a sacred cave, and left him in the care of the nymphs and their mother Melissa (or two nymphs Melissa and Kinosura). In gratitude, Zeus later ascended to heaven Melissa in the form of Ursa Major and Kinosura in the form of Ursa Minor; on ancient maps, Ursa Minor (or just the North Star) is sometimes called Kinosura (“ dog's tail"). Note that in early versions of the myth, Melissa and Kinosura are bears, who later transformed into nymphs.

The Phoenicians, the best navigators of early antiquity, used the constellation for navigational purposes, unlike the Greeks, who navigated by the Big Dipper, which is obviously less accurate.

The peoples of Kazakhstan called the North Star an “iron nail” ( Temir-Kazyk), driven into the sky, and in the remaining stars of Ursa Minor they saw a lasso tied to this nail, worn around the neck of the Horse (constellation Ursa Major). The Arabs mistook the stars of Ursa Minor for horsemen, and the Persians saw in it the Seven Fruits of the Date Palm.

Constellation Ursa Minor from the Atlas "Uranographia" by John Hevelius (1690)

click on the image to enlarge it

There are constellations in the sky that almost everyone knows about. These include the constellation Ursa Minor.

The constellation Ursa Minor is located in the subpolar region of the sky and contains 25 stars. But for most people, only seven of them are known, forming an asterism called the Little Dipper. The most popular star of the constellation is, whose location almost coincides with North Pole peace. In addition to fairly bright luminaries, the constellation contains a small elliptical galaxy, nicknamed the Ursa Minor Dwarf for its size.

Location

Constellation Ursa Minor, view in the Stellarium planetarium program

Finding a constellation in the sky is quite simple. Its neighbors are the Giraffe, the Dragon and the Cepheus. But it usually serves as a guide for searching. By drawing a line with your gaze through the two outer luminaries of its bucket, and measuring up five distances between them, you can find the Polar Star, which serves as the beginning of the “handle” of another, smaller “scoop”. This will be Ursa Minor. It is less bright than the Big One, but is still clearly visible in the sky and is easily distinguishable from other constellations. In the Northern Hemisphere, this constellation is available for observation all year round.

North celestial pole

A point is called a pole celestial sphere, which appears stationary to an observer on Earth, while all other objects rotate around it. If there is a nearby bright star, then it can serve as a guide, since its location does not depend on the time of day. Due to the peculiarities of the Earth's movement, this point moves, but on a scale of centuries it can be considered unchanged. Currently, the North Star is closest to the pole. It is only 40 arc minutes away from it in angular terms.

North Star

Alpha Ursa Minor is located 434 light years from Earth and has an apparent magnitude of 1.97. But in fact, this is not one luminary, but three, united into a system. The largest of them is 4.5 times more massive than the Sun and two thousand times brighter. The second largest star is located at a fairly decent distance from the main one; it can even be viewed with a small telescope. The mass of the star is approximately 1.39 solar. The third star is so close to the first that they could only be visually separated using the telescope "", and even then, this was done with with great difficulty. It is 1.25 times heavier than the Sun.

The second brightest luminary of Ursa Minor is its beta, which has an apparent magnitude of 2.08. The star is approximately 126 light years away from Earth. Its name translated from Arabic means “Star of the North”, since for a certain period of time BC (approximately from 2000 to 500) Kohab was located closest to the pole than any other star and served as a navigational landmark for the peoples living at that time. In 2014, Korean astronomers discovered a planet near this double star whose mass exceeds Jupiter’s by 6.1 times. The orbital period of this gas giant is 522.3 days.

Gamma Ursa Minor is located at a distance of about 480 light years from Earth and has an apparent magnitude varying in the range of 3.04-3.09. The period of change in the brightness of the star is 3.43 hours. This third brightest object in the constellation is a hot giant with a temperature of about 8600 K. Its luminosity exceeds that of the Sun by 1.1 thousand times, and its dimensions are 15 times larger than our yellow dwarf. According to the classification, it belongs to the variable luminaries of the T Shield type.

Asterisms

The constellation contains two asterisms: the Small Dipper and the Guardians of the Pole. The first is well known to modern observers. It is very similar to the Big Dipper located nearby, but is only less bright. It is formed by the most visible luminaries of the celestial formation. Quite a lot of people believe that Ursa Minor is limited to these seven objects, although in fact it contains 18 more stars.

The second asterism is much less known and its name goes back to ancient times, when the two luminaries forming it, named Ferkad and Kohab, were located closer to the pole than the North Star.

Meteor showers

Ursa Minor serves as the radiant of the last “starburst” of the year, which has been studied rather poorly. Its radiant lies near the Little Dipper, the meteor shower occurs from December 17 to 25 and is extremely unpredictable. Usually, on the most active days, from 10 to 20 meteors are visible in it per hour, which is of little interest to the average observer. But there are unpredictable bursts of activity when their number exceeds a hundred. Such “fruitful” years for meteors were 1988, 1994, 2000, 2006, and especially 1945 and 1986. This is the northernmost of these showers - it owes its birth to the short-period comet Tuttle.

In addition to the main stars, the galaxies located in Ursa Minor are of interest. The already mentioned Dwarf, which is a satellite Milky Way, was discovered in 1954. This is a fairly old galaxy, at least ten billion years old. It is too small to see if it contains gas, dust or any star formation. Sometimes, due to its location close to the Earth's rotation axis, it is called Polarissima.

In addition, the constellation contains the galaxies NGC 6217 and NGC 5832. All of these objects are very small on a cosmic scale, and therefore it is impossible to observe them without good optical equipment.

History of the constellation