The third largest constellation in the sky... An invaluable find for every true astronomy lover living in the northern hemisphere of the Earth. Inside and around the Big Dipper, telescopes find many interesting objects, which, at the same time, are available for observation almost all year round!
Here, every observer will find an object to their liking. Ursa Major has dozens of binary and variable stars available for visual inspection, some beautiful asterisms, a planetary nebula, and even an open star cluster. But the main characters galaxies, of course. Ursa Major is a window to the Universe; looking at this section of the sky, we easily penetrate a thin layer of stars nearby the Sun and rush into the boundless depths of space. Neither star clouds nor galactic dust prevent us from exploring distant galaxies, because Ursa Major is located away from Milky Way.
in the constellation Ursa Major there is a myriad of galaxies, many of which are grouped together, as in this picture. Almost a thousand galaxies are available for observation in large amateur telescopes in the suburban sky. A photo: Dr. Stefan Binnewies/Josef Popsel
Even a simple listing of all the objects that can be observed in this constellation with an advanced amateur telescope would take up an unreasonable amount of space. Keeping in mind that most amateurs do not have super-expensive instruments, they observe from time to time and in not the most pleasant conditions (flare, cloudiness, and so on), we tried to select only those objects that are the most interesting and exciting, objects that we try to see every true connoisseur of the starry sky should.
But even here we had to divide the article into two parts. In the first part, we will get acquainted with the stars and star patterns of Ursa Major, and the second part will be devoted to deep space objects - nebulae and galaxies. In both cases, we will pass this gigantic section of the sky along and across: from the tip of the tail to the muzzle of the celestial beast and from its withers to its paws. Of course, we will focus on the objects inside the Big Dipper - there is something to see there!
What do we need to travel?
- Firstly, you need to get a good star atlas or a set of star charts. This is necessary for orientation in the sky and search for the necessary objects - stars, nebulae and galaxies. You can, of course, use the services of a planetarium program such as Stellarium, but during observations it would be better to have maps at hand - in paper form. In any case, for most of the objects described below, we provide drawings for their search.
- Secondly, equipment. To observe variables and some double stars good astronomical binoculars will suffice. The same applies to asterisms and the brightest galaxies. To observe the rest of the objects, you will need a telescope with a 90 mm lens or higher. (Telescopes with a smaller lens are only good for observing some double stars, and other objects are best observed with binoculars with the same or even a slightly smaller lens.) Obviously, the larger the telescope you have, the fainter objects you will be able to see.
- Thirdly, a truly dark sky is highly desirable. If the described stars can still be observed in the city, then in order to examine nebulous objects it is necessary to reduce the illumination to a minimum. If you have such an opportunity - use it.
Well, now we can begin our journey!
The first and simplest object in the constellation Ursa Major, which is perfectly visible to the naked eye at any time of the year, of course. This star pattern, formed by seven stars of approximately the same brightness, is known to almost everyone since childhood. The bucket itself is not a constellation, it is only a part, albeit the brightest, of the constellation Ursa Major. Such memorable star patterns that are not constellations are called.
The Big Dipper has played an important role in the life of civilization for thousands of years, helping sailors, nomads and travelers to navigate the terrain. Not surprisingly, all of its stars have their own names, and some even have several names! Here they are, if listed from right to left, from the bucket to its handle: Dubhe, Merak, Fekda, Megrets, Aliot, Mizar and Benetnash (or Alkaid). All names are of Arabic origin; they sound unusual, but in translation they mean rather prosaic things, such as: “back”, “thigh”, “lower back”, “base of the tail” and so on.
Big Dipper over the pagoda. A photo: flickr.com/Syu2
Look closely at the stars of the Big Dipper when this asterism is high in the sky and the stars are not twinkling. Did you notice anything? All Stars white color, with the exception of the star Dubhe, the topmost star in the bucket, which is yellowish in color. It is strange, isn't it, to see such a cluster of stars comparable in color and brightness in a fairly small area of the sky? Perhaps something similar is observed only in the constellation of Orion, where all the bright stars, with the exception of Betelgeuse, are like two drops of water. Perhaps this arrangement of stars in our sky is not accidental?
Really, five of the seven bucket stars are related to each other by a common origin. Observations made in the second half of the 19th century showed that Merak, Fekda, Megrez, Aliot and Mizar are approximately the same distance from us (about 80 light years) and fly in space more or less in the same direction. When astronomers seriously took up the inventory of their celestial economy, it turned out that in the vicinity of the Big Dipper there are about a dozen more stars that follow the galactic orbit along with our five. Among them is Mizar's optical companion, the star Alcor!
Ursa Major moving group(other name Collider 285) is the closest open star cluster to Earth. The distance to its center is estimated at 75-80 light years, and the diameter of the cluster is 30 light years. True, here it is necessary to clarify that by now about 40 more stars have been identified that may belong to the group. The Ursa Major Stream, as astronomers call the collection of these stars, includes luminaries scattered throughout the sky - from the constellation Cepheus to the Southern Triangle. If their membership of the cluster is confirmed, this would mean that the Ursa Major Moving Group is much larger than we imagine, and the Sun is currently inside the cluster.
Does this mean that the solar system is part of an open star cluster? No. The age of the Ursa Major Moving Group does not exceed 300 million years - the Sun is almost 10 times older. The velocities and motion vectors of the stars in the cluster are the same, but not equal to the solar ones: the cluster moves obliquely with respect to the solar system, flying past at a speed of 46 km/s. Conclusion: we are random fellow travelers in this dance of the luminaries.
Other asterisms
In the Big Dipper there are some more entertaining asterisms, which, however, are not as easy to find as the Big Dipper. To observe them, you will need good astronomical binoculars with a lens over 50 mm and a not too illuminated sky, since the stars that make up these drawings are quite weak.
Broken wedding ring
This is perhaps the most famous telescopic asterism in the constellation. Compact and expressive enough, it is an excellent target for binoculars and small telescopes. The asterism consists of ten stars 7 m - 11 m , forming a semi-ring with a diameter of half the lunar disk. The brightest star in this chain looks like a diamond embedded in a ring.
Asterism A broken wedding ring in the constellation Ursa Major (bottom of the image). A photo: DSS2
Actually, it is thanks to its characteristic shape that this tiny star pattern got its name, although some observers argue that the asterism is more like a papal tiara than a wedding ring, albeit a broken one.
Finding the Broken Wedding Ring is easy: the asterism is located 1.5° west (to the right) of the star Merak, the lowest star in the Big Dipper. By the way, this pseudocluster also has an “official” name: Sachariassen 1.
Asterism A broken wedding ring is located at a distance of three discs of the Moon from the star Merak. Picture: Stellarium/Big Universe
Shovel
We wrote above that Ursa Major is a real treasure trove of interesting space objects. To dig it out, you need a good shovel. And she is available!
Be sure to take a look at the Spade asterism, which is located between the stars phi (φ) and theta (θ) Ursa Major!
The heavenly "shovel" is located between the stars phi and theta Ursa Major. Picture: Stellarium
With 50mm binoculars, you will only see a string of rather faint stars, however, armed with a more powerful tool, such as binoculars with a 70mm lens or a telescope with a wide field of view, you can easily find this important treasure hunt tool!
Shovel photograph taken as part of the Digital Sky Survey project. A photo: DSS2
The figure of asterism is formed by 11 stars 8 m - 10 m; the brightest are the handle of the shovel and its lower rim. The place of attachment of the handle and the upper part of the shovel itself are marked with stars of the 10th magnitude. Please note: the tip of the shovel is blunt, there is clearly one star missing! Therefore, this is a slightly strange shovel, a cross between a shovel and a bayonet.
Traveling from the star Merak to Theta Ursa Major, you can sequentially consider both the Broken Wedding Ring and the Spade. Picture: Stellarium
The diameter of the asterism is 1° or two apparent diameters of the Moon. It is best to observe the Shovel in its entirety, of course, through binoculars, but it also looks quite good in a telescope with a wide field of view.
Another memorable and very easy to see asterism is close to Mizar and Alcor. We have named this asterism "Pistol", referring to the dispenser pistol handle; English-speaking observers call it Gas Pump Handle - the meaning is preserved.
Asterism The pistol is in the handle of the Big Dipper between Mizar and Benetnash. Picture: Stellarium
The basis of the asterism is formed by four stars of the 6th and 7th stars. led., forming an irregular parallelogram. The brightest of these stars, 82 Ursa Major, is visible outside the city at the limit of visibility even with the naked eye, so finding a parallelogram with binoculars will not be difficult.
Now the most interesting: above the star 82 Ursa Major you will see two more stars 7 m. This is the nose of the gun, where the space fuel comes from. Where is the lever? Inside the parallelogram! It is formed by a chain of stars 9 m - 11 m, coming from 82 Ursa Major.
With some imagination, the tanker's pistol is quite easily recognizable in this star pattern. Picture: DSS2/Greater Universe
You will see the pistol lever clearly only in a dark sky in an instrument with a lens larger than 70 mm, but the main pattern is perfectly visible already in 50 mm prism binoculars.
By the way, pay attention to the star HD 118668, which is part of this asterism. It is a distant red giant located at least 1000 light years away. years from Earth! In addition, there are suspicions that it changes its brilliance within 1.5 m.
The last, fifth in a row, asterism known in Ursa Major can be observed with the naked eye. It's called "Horse and Rider" and represents two closely spaced stars, Mizar and Alcor. But it will be discussed below, in the section on double and multiple stars.
Double and multiple stars in Ursa Major
There are a huge number of double stars in the constellation Ursa Major, but not all of them are of interest to a simple amateur astronomer. Most of them are either too faint to make a proper impression, or too close for small telescopes.
Orbits of close binary stars ι Ursa Major and Dubhe (α constellation). Source: Burnham's Celestial Handbook
On the other hand, Ursa Major has probably the most famous visual double in the entire sky. And Mizar himself is just a reference double star that every owner of a telescope should see! Let's start with this couple.
Mizar and Alcor
Mizar- the second star, if you count from the end of the handle of the Big Dipper. It is located on the bend of the handle, so it is incredibly easy to find it. You will not confuse Mizar with neighboring stars also because it has a satellite - a faintly luminous star 4 m, which Arab astronomers gave the name Alcor. Traditionally, Mizar is translated from Arabic as "Belt" or "Sash", and Alcor as "Weak" (from the word Al Khawwar), but we used to call them the Horse and the Rider. This well-known name is not a translation of their names - this is how Europeans called a couple in the Middle Ages. In fact, Mizar and Alcor - Horse and Rider - this is another fifth asterism of Ursa Major.
A pair of stars, Mizar and Alcor, mark the bend in the handle of the Big Dipper. Picture: Stellarium
Outside the city on a dark night, Mizar and Alcor are perfectly visible - in the old days, many peoples checked the sharpness of their eyes using this pair. But today it is difficult to check eyesight in this way: in Moscow and other major cities Alcor is simply not visible due to strong illumination!
But Mizar and Alcor are simply an incredible beauty of the sight, if you look at them through a telescope. Look at the pair first using the lowest magnification. First, pay attention to the color of the stars: it is white with a slight blue tint. Next, take a look at your surroundings: a few other fairly bright stars serve as a nice backdrop. Finally, take a closer look at Mizar. You will find that it consists of two closely spaced stars! .. Amazing picture!
Mizar and Alcor. A photo: DSS2
Mizar and Alcor are separated in our sky by 12 arc minutes - almost a third of the lunar disk. In reality, the distance between the stars is almost a quarter of a light year. For a long time, there were discussions in the scientific community whether this couple is physically connected or not. The point was put in 2009, when astronomers at the University of Rochester made more accurate measurements and showed that both stars are part of a physically connected system consisting of ... 6 stars! It turns out that both components of Mizar and Alcor itself - all three stars are double! Mizar A and Mizar B are spectral binaries; the components in these systems are so close to each other that they cannot be separated in any telescope. Alcor has a companion, a dim red dwarf, at a distance of 1″ - it was discovered on images in 2009.
ξ Ursa Major
This is perhaps the most notable double star in Ursa Major after Mizar. It can be found on one of the hind legs of the Bear, south of the other bright stars of this constellation.
Xi Ursa Major is the southernmost star in the constellation visible to the naked eye. Picture: Stellarium
Xi Ursa Major interesting because it is the first binary star for which an orbit was calculated and the period of revolution was reliably determined. It happened back in 1830! Since then, the stars have orbited their common center of mass three times, allowing astronomers to refine their orbit and period, which is now thought to be 59.878 years.
Orbit ξ Ursa Major. The dots mark the position of the satellite star in different years. Source: James Mullaney. Double and Multiple Stars and How to Observe Them
Both components are very similar in their characteristics to the Sun. The main star with a magnitude of 4.41 m is separated from the companion of 4.87 m at a distance of 2.5″, which makes it possible to separate the pair into telescopes with a lens over 80 mm. Spectral studies have shown that each of the components, in turn, is a double star. The companions are cool red dwarfs of class M, but there is no exact information about these stars. Finally, in 2012, another component of the system was discovered - a distant brown dwarf of spectral type T.
Thus, we have another complex system, consisting of 5 luminaries! It is located at a distance of 29 light years from Earth.
σ² Ursa Major
Another interesting double star - sigma² Ursa Major located to the right of the bucket. The brightness of σ² is 4.80 m - it is quite visible to the naked eye in the suburban sky. The color of the star is white with a yellowish tint. Together with the star σ¹, it makes up a wide pair of stars, comparable to Mizar and Alcor, but, of course, not as bright and noticeable. This is an optical double star, that is, its components are not physically connected to each other, are located at different distances from the Earth and ended up in the same part of the sky quite by accident.
The star sigma2 Ursa Major is located in the sky next to the famous pair of galaxies M81 and M82. Once you've had your fill of the distant stellar islands, point your telescope at the double star and view it at high magnification! A photo: DSS2
Together with the star ρ Ursa Major, the pair forms a small isosceles triangle. On ancient maps, the ears of the Bear were depicted in this place. Explore the area with binoculars, and then examine the star σ² separately through a telescope.
At high magnification, you will notice that sigma² consists of two stars - a companion with a magnitude of 8.3 m is located at a distance of 4 "from the main star. The pair was discovered by Sir William Herschel in 1783, and the positions of the components have been measured since 1832, when Vasily Struve examined the star. As observations have shown, the period of revolution in this system is about 1100 years! The stars passed the periastron in the first half of the 20th century and are now moving away from each other. The angular distance between the components is slowly growing and will continue to grow for another 200 years!
Orbit of the double star σ² Ursa Major. The dots mark the position of the satellite star in different years based on a 700-year period. Source: Robert Burnham's Celestial Handbook
The distance to this pair is 66 light years. This means that the main star is 5 times brighter than the Sun, and its companion is 5 times dimmer. Apparently, σ² B is a typical orange dwarf.
Below is a list of interesting double stars in Ursa Major. For stars, the coordinates, the brightness of the components, the angular distance between the components, and the period of revolution, if known, are given.
List of double and multiple stars in Ursa Major
| Star | α (2000) | δ (2000) | V | Angular dist. | Period | Notes |
|---|---|---|---|---|---|---|
| ι B. Ursa | 08h 59 min | +48° 02" | 3.1m + 10.2m | 2,0" | 817.9 years | B - double 0.2" |
| Σ 1280 | 08 56 | +70 48 | 7,5 + 7,5 | 1,9 | ||
| σ² B. Ursa | 09 10 | +67 08 | 4,8 + 8,2 + 9,3 | 4,5; 205 | 1100 | |
| τ B. Ursa | 09 11 | +63 30 | 4,7 + 10,5 | 57,1 | optical dv. | |
| Σ 1321 | 09 14 | +52 41 | 7,6 + 7,7 | 17 | 975 | |
| 23 B. Ursa | 09 32 | +63 04 | 3,7 + 8,9 | 22,9 | ||
| φ B. Ursa | 09 52 | +54 04 | 5,3 + 5,4 | 0,3 | close couple | |
| Σ 1495 | 11 00 | +58 54 | 7,2 + 9,5 | 34 | ||
| α B. Ursa | 11 04 | +61 45 | 1,9 + 4,8 + 7,0 | 0,7; 378 | 44,7 | close couple |
| ξ B. Ursa | 11 18 | +31 32 | 4,4 + 4,9 | 1,8 | 59,878 | 5 times |
| ν B. Ursa | 11 19 | +33 06 | 3,5 + 9,9 | 7,2 | ||
| 57 B. Ursa | 11 29 | +39 20 | 5,3 + 8,3 | 5,4 | ||
| ΟΣ 235 | 11 32 | +61 05 | 5,8 + 7,1 | 0,7 | 73 | |
| Σ 1561 | 11 39 | +45 07 | 6,3 + 8,4 + 8,5 | 9; 85 | ||
| 65 B. Ursa | 11 55 | +46 29 | 6,7 + 8,3 + 6,5 | 4,63 | triple | |
| 78 B. Ursa | 13 01 | +56 22 | 5,0 + 7,4 | 1,5 | 115 | |
| ζ B. Ursa | 13 24 | +54 56 | 2,3 + 4,0 | 14,4 | Mizar; 4-fold system | |
| 80 B. Ursa | 4,0 | 708,7 | Alcor; cn. double |
variable stars
The choice of variable stars in Ursa Major is huge: in the database on the AAVSO website, there are more than 2800 variable stars in this constellation! The bad news is that almost all of them are quite dim - you need a good telescope to study them.
Of those stars that can be observed with rather modest amateur means, we single out three: W, R and VY Ursa Major. The first star belongs to the eclipsing variable stars, R Ursa Major is a long-period variable or Mirida, and the third, VY Ursa Major, belongs to semiregular variables.
W Ursa Major
Especially interesting is the star W Ursa Major. It belongs to the type of so-called eclipsing variables. The well-known "devil's star", Algol, belongs to the same type, but W Ursa Major is a much more extreme example of this kind of stars.
See for yourself. Like all eclipsing variables, W Ursa Major is a double star. The components that make up this system are very similar in their characteristics to our Sun, but are located so close to each other that, under the influence of mutual attraction, they changed their usual spherical shape and turned into elongated ellipsoids. Moreover, both stars filled the so-called Roche lobe and touch each other at one of the Lagrangian points! Circling around a common center of mass, these two melon-shaped luminaries are always turned to each other with "sharp" sides, exchanging matter.
During the revolution, the stars W of the Big Dipper turn to the Earth either with a narrower or with a wider part. This also leads to a change in the amount of light coming in our direction, which is expressed in a drop in the brightness of the star from 7.8 m to 8.6 m. The most incredible thing about this system is the period of revolution of the components: it is only 8 hours or 0.33 Earth days! This means that the entire cycle can, in principle, be tracked within one night!
You can observe Ursa Major W with binoculars or a telescope. The star is located just below Upsilon Ursa Major, almost halfway to the star Theta.
W of the Big Dipper is located between the body and the front paw of the celestial beast. Picture: Stellarium/Big Universe
After identifying a star in the sky, you may want to verify its variability and maybe even start serious research. Below is a map of the vicinity of Ursa Major W, on which the brightness of comparison stars is marked with numbers. (80 means magnitude 8.0 m, etc.) Note that the image on the map is inverted, as in a reflecting telescope. To use it with binoculars, rotate it 180 degrees.
Map of the vicinity of Ursa Major W with comparison stars.
The most conspicuous and well-known constellation to all, without exception, is, of course, Ursa Major. More precisely, it is not she herself that is clearly visible in the night sky, but part of her - the Big Dipper. If you look closely, then below and to the right of it you can see a few more stars that make up the paws and head of the Bear. The shape of this constellation is really very fascinating. After all, no one has ever seen bears with such long tails.
The number of bright stars in the Big Dipper bucket is clear to everyone. There are exactly seven of them. The name of these stars was given by Arab astrologers in the Middle Ages.
To our ears, their “names” sound really strange:
- Merak.
- Mizar.
- Fegda.
- Megrets.
- Dubge.
- Aliot.
- Benetnash.
From the earth, these stars appear equidistant. In fact, this is far from the case. The number of bright stars in the Ursa Major bucket is seven, and they are all not at equal distances from the Earth and the Sun.
Closest to our planet is Benetnash. The farthest star, Alioth, is sixty light-years away. However, it looks brighter than Benetnash. This is the brightest and most brilliant object of the Bucket. According to the apparent intensity of the emitted light, all the stars of this part of the Big Dipper are close to the stars of the 2nd magnitude.
Noteworthy Facts
If you look very closely at one of the stars of the Bucket - Mizara, you can see a faint flicker right next to it. This is explained very simply. Mizar is not an ordinary star, but a double one.
The facility located right next to it is called Alcor. From Arabic, these two words are translated as "Horse" and "Rider". Alcor and Mizar are one of the most visible double stars from Earth.
The number of bright stars in the Big Dipper bucket is seven. However, if you look at it through binoculars or a telescope, you can see two more small strokes of light. Unlike stars, they look fuzzy and blurry. This is how distant galaxies look from Earth. Located inside the Ursa are called Whirlpool and Pinwheel.
Rotation of the Huge Bucket
The fact that our Earth does not stand still is clear to any schoolchild. Due to its movement, it seems that the stars in the sky are spinning. The Bucket is no exception in this regard. In winter and autumn, Ursa Major is located in the northern part of the night sky, not too high from the horizon. In spring and summer, this most conspicuous constellation can be seen almost at its zenith. And at this time of the year, Ursa Major looks upside down.
celestial compass
So, the number of bright stars in the Big Dipper bucket is exactly seven. Two of them can serve as a guide for those who are on the road. The fact is that it is easy to detect the most famous star in the world - the Polaris. It's easy to do. It is only necessary to draw an imaginary line along the two outer stars of the Ladle bowl. Further on it should measure approximately the distance between them. The North Star itself is located almost above the northernmost pole.
In ancient times, when there were no navigational instruments yet, it specifically served as a guide for all sailors and travelers. So, if you suddenly find yourself in a difficult situation in an unfamiliar area - look at the constellation Ursa Major. The polar star found on it will show you the way to the north. This one is small and not too bright celestial object already far more than once rescued those lost in the taiga, in the desert or at sea. The North Star leads the nearest neighbor of Ursa Major - Ursa Minor. The area of location of both these "animals" is considered circumpolar according to the systematization of astrologers.
How many stars are in the Big Dipper
Of course, in this constellation itself there are even more stars than in its most conspicuous part - the Bucket. At the moment, there are about 125 of them. These are over a hundred bright objects, against which the Sun would look like a small and dim luminous dot. The closest star to Earth, unfortunately, is not even visible to the naked eye. She also does not have a name. According to astronomical systematization, it passes as a star of 7.5 m. The light from it to the Earth takes about 8.25 years. This is almost twice as much as from the closest star to us - Alpha Centauri. Thus, the answer to the question of how many stars are in Ursa Major is simple - more than a hundred and not all of them are visible without a telescope or binoculars. To see a feral animal with a long tail in the Bucket, you actually need to have a fairly rich imagination.
Legend of the Big Dipper
Of course, about such conspicuous objects of the night sky as the stars of the constellation Ursa Major, there simply cannot but exist many different kinds of myths and legends. The most popular legend about her was invented by the Greeks. The chroniclers of this old country say that once the king of Arcadia had an unusually beautiful daughter, Callisto. And this woman was so proud of her attractiveness that she dared to compete with Hera herself, the wife of Zeus. The enraged goddess, using her mystical power, of course, took revenge on the proud woman, turning her into a bear. The son of Callisto Arcas, who was returning from hunting at that time, saw a feral animal at the door of the palace and decided to kill him. However, at the last moment he was stopped by Zeus, who was not indifferent to the beauty. After the rescue, Callisto was raised to heaven. The stars of the Ursa Major bucket are what it is. At the same time, the supreme god raised the beauty’s beloved dog to heaven. Now it is known under the name Ursa Minor.
nearest constellations
The stars in the constellation Ursa Major, or rather in its Bucket, are the most noticeable in the night sky. However, in addition to Ursa Minor, there are several more recognizable constellations in this area. The reference point for finding one of them can be the same Polar Star. Behind her, on the opposite side from the Big Dipper, at approximately the same distance, Cassiopeia, familiar to many by name, flaunts. From the outside, this constellation looks like the Russian letter "M". At some positions of the Earth, Cassiopeia "turns over" and takes the form of a Latin W.
Between it and Ursa Minor, you can see the not so noticeable, but also the notorious constellation Cepheus. It does not have a clearly visible form. Between Ursa Major and Ursa Minor, it is also easy to see a wriggling Dragon. The chain of its stars is easily connected on the map by a broken line.
Well, we hope we answered main question articles about how many luminous permanent objects there are in Ursa Major. There are only seven of them in the Bucket. The main constellation contains about 125 distant "suns".
Ursa Major (lat. Ursa Major) - constellation northern hemisphere sky. The seven stars of Ursa Major make up a figure resembling a ladle with a handle. The two brightest stars, Aliot and Dubhe, have magnitudes of 1.8 apparent magnitudes. According to the two extreme stars of this figure (α and β), you can find the Polar Star. The best visibility conditions are in March-April. It can be seen throughout Russia all year round (with the exception of the autumn months in southern Russia, when the Big Dipper descends low to the horizon).
Short description
| Big Dipper | |
| Lat. title | Ursa Major (genus n. Ursae Majoris) |
| Reduction | UMa |
| Symbol | Big Dipper |
| right ascension | from 7 h 58 m to 14 h 25 m |
| declination | from +29° to +73° 30’ |
| Square | 1280 sq. degrees (3rd 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 -16°. The best time to watch is March. |
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Detailed description
The constellation Ursa Major is located in the northern hemisphere of the starry sky.. People have known it for thousands of years. He was known by the astronomers of Egypt, Babylon, China and Ancient Greece. It was included by Claudius Ptolemy in his monograph Almagest as early as the 2nd century. And this work combined all the knowledge of astronomy at that time.
The Big Dipper is formed by the following seven stars:
- Dubhe (Alpha Ursa Major), the name comes from the Arabic expression - "the back of a big bear."
- Merak (β) - from Arabic "loin" or "groin"..
- Fekda (γ) - "thigh".
- Megrets (δ) - "base of the tail". It is the dimmest star among the stars of the Big Dipper.
- Aliot (ε) - "fat tail". The brightest star in this constellation.
- Mizar (ζ) - from Arabic - "belt". Near Mizar there is another star - "Alcor". It is noteworthy that the ability to distinguish between these two stars is a consequence of good vision (with myopia no more than 1 diopter).
- Benetnash (η) or otherwise - Alkaid. The third brightest star in Ursa Major. "Al-Qaeed banat ours" is translated from Arabic as "the leader of the mourners."
As you can see, this formation includes 7 stars. If you connect them with a straight line, you get a figure that resembles a bucket with a handle. Each star has its own name. At the top of the bucket, opposite the handle, there is a star called Dubhe. It is the second brightest among its cosmic counterparts. This is a multiple star. That is, several stars from the Earth are seen as one due to the close distance to each other.
In this case, we are dealing with 3 stars. The largest of them is a red giant. That is, the core has already lost all its hydrogen reserves, and thermonuclear reaction goes to the surface of the luminary. It dies, and in time should turn into white dwarf or become black hole. The other two stars are Main Sequence stars, that is, the same as our Sun.
On the same straight line with Dubhe, at the base of the bucket, there is a star Merak. This is a very bright light. It is 69 times brighter than our Sun, but due to the vast space it does not make the proper impression. If the straight line between Merak and Dubhe is extended towards the constellation Ursa Minor, then you can rest against the North Star. It is located at a distance that is 5 times the distance between the indicated luminaries.
The other lowest point of the bucket is called Fekda. This is a Main Sequence star. The upper point of the bucket opposite it is called Megrets. She is the dullest in a friendly company. This star is almost 1.5 times larger than our star and 14 times brighter.
There is a star at the beginning of the handle Aliot. It is the brightest in the constellation Ursa Major. Among all the visible stars in the sky, it ranks 33rd in brightness. From the end of the handle, it is the third in a row, and the second is a star. Mizar. Next to it is another luminary, which is called Alcor. Anyone with good eyesight can see it. They say that in ancient times, Alcor was used to test the visual acuity of young boys who aspired to become sailors. If a young man could see this star next to Mizar, then he was enlisted as a sailor.
In reality, not 2 stars, but as many as 6 shine in the space distance. These are the double stars Mizar A and Mizar B, as well as the double star Alcor. But from the Earth, with the naked eye, only a large bright dot and a small one, which is nearby, are visible. These are the surprises sometimes presented by space.
And finally, the most extreme star. It is called Benetnash or Alkaid. All these names are taken from Arabic. In this case, the literal translation means "the leader of the mourners." That is, the al-qaid is the leader, and our banat is the mourners. This luminary is the third brightest after Aliot and Dubhe. It ranks 35th among the brightest stars in the sky.
The brightest stars in Ursa Major
| Star | α (2000) | δ (2000) | V | Sp. Class | Distance | Luminosity | Notes |
| Aliot | 12h 54min 01.7s | +55° 57′ 35″ | 1,76 | A0Vp | 81 | 108 | |
| Dubhe | 11 03 43,6 | +61 45 03 | 1,79 | K0IIIa | 124 | 235 | Triple. ΑΒ=0.7″ AC=378″ |
| Benetnash | 13 47 32,3 | +49 18 48 | 1,86 | B3V | 101 | 146 | |
| Mizar | 13 23 55,5 | +54 55 31 | 2,27 | A1Vp | 86 | 71 | 6 star system including Alcor Α and Β |
| Merak | 11 01 50,4 | +56 22 56 | 2,37 | A1V | 78 | 55 | |
| Fekda | 11 53 49,8 | +53 41 41 | 2,44 | A0Ve | 84 | 59 | |
| ψ UMa | 11 09 39,7 | +44 29 54 | 3,01 | K1III | 147 | 108 | |
| μ UMa | 10 22 19,7 | +41 29 58 | 3,05 | M0III | 249 | 296 | cn. double? |
| ιUMa | 08 59 12,4 | +48 02 30 | 3,14 | A7IV | 48 | 10 | cn. double and opt. double |
| θUMa | 09 32 51,3 | +51 40 38 | 3,18 | F6IV | 44 | 8 |
Other objects of Ursa Major
In addition to the Big Dipper, in the constellation Ursa Major, you can also observe an asterism called "Three Gazelle Jumps", which looks like three pairs of stars.
These are the following couples:
- Alula North South (ν and ξ),
- Taniya North and South (λ and μ),
- Talita North and South (ι and κ).
Near Alupa Severnaya is a red dwarf called Lalande 21185, which is elusive to observe with the naked eye. However, it is the sixth closest star system to the Sun. Closer than the stars Sirius A and B.
Observational astronomers are well aware that this constellation contains the galaxy M101 (called the Pinwheel), as well as the galaxies M81 and M82. The last two form the core of what is probably the nearest group of galaxies, located at a distance of about 7 million light years. Unlike these distant objects, the astronomical body M 97 ("Owl") is located within the Milky Way, hundreds of times closer. The Owl is one of the largest planetary nebulae.
In the middle, between the first and second "gazelle jump", with the help of optics, you can see a small yellow dwarf, similar to our Sun at number 47. From 2000 to 2010, scientists discovered three exoplanets, gas giants, orbiting it. Also, this star system is one of the most similar to the solar system and takes 72nd place in the list of candidates for the search for planets similar to Earth, carried out as part of the planned NASA Terrestrial Planet Finder mission. So for an astronomy lover, the constellation is of great interest.
In 2013 and 2016, two of the most distant galaxies from us were discovered in the constellation, respectively z8 GND 5296 and GN-z11. The light of these galaxies, recorded by scientists, was 13.02 (z8 GND 5296) and 13.4 (GN-z11) billion years.
This is how you can characterize the constellation Ursa Major, known since ancient times. This space region also includes many galaxies. For example, the Pinwheel galaxy. It is better known as M 101. In size, it exceeds the Milky Way. Her detailed pictures were taken by the Hubble telescope at the beginning of the 21st century. To get to this huge cluster of stars, you need to spend 8 million light years.
The Owl Nebula is also of interest. It enters our galaxy and looks like 2 dark spots located side by side. In 1848, Lord Ross considered these spots to be like the eyes of an owl. That's where the name came from. This nebula is about 6 thousand years old, and it is located at a distance of 2300 light years from the solar system.
But the most interesting thing is that the constellation Ursa Major is considered as one of the likely sources of extraterrestrial intelligence. In this part of space there is a certain star named 47UMa. This is a yellow dwarf, and its planetary system is very similar to ours. solar system. At least, today 3 planets are known that revolve around this star. In 2003, a radio message was sent to him. Earthlings are persistently looking for brothers in mind, and luck always accompanies the stubborn.
How to find the Big Dipper in the sky?
If you want to learn how to navigate the starry sky, then your primary task is to be able to find the Big Dipper bucket. Although it is not far from the North Star, it is still not so close to it as to be at the same point in the sky all the time.
The Big Dipper is easiest to spot in autumn and winter. At this time, in the evenings, the asterism is located in the north, not high above the horizon and in the position we are used to.
By the end of winter, the position of Ursa Major in the evening sky changes. The seven stars of the bucket move to the east, and the Big Dipper itself stands upright on the handle.
There is nothing surprising. Recall that every day all the stars describe circles around the pole of the world, thereby reflecting the rotation of the Earth around its axis. But during the year, the stars make one more additional circle, thereby reflecting the movement of the Earth in orbit around the Sun. The stars of the Big Dipper are no exception - shifting from the bottom point, the bucket, as it were, rears up.
In the middle of spring, Ursa Major is at its zenith in the evenings, right above your head! At this time, he is in an inverted position in relation to the North Star. Her bucket faces west, and the handle of the bucket faces east.
For those who live north of Moscow, it is most difficult to find the Big Dipper in the sky in the summer, during the period of short nights. At this time, the constellation is in the west, and the bucket is tilted down and looks north.
How to find the North Star in Ursa Major?
Now let's see how to find the North Star using the Big Dipper. This is done simply. Take the two extreme stars in the bucket, Dubha and Merak (alpha and beta Ursa Major) and mentally connect them with a line. And then extend this line five times the distance Merak - Dubhe.
You will see a star whose brightness is approximately equal to the brightness of the bucket stars. This is the famous Polar Star, the "iron nail", as the Kazakhs called it, referring to the immobility of the Polar Star in the earth's sky.
Knowing the position of the North Star, you can easily navigate in space. Spend plumb line from Polar down. The place where it intersects with the horizon will point north. The rest of the cardinal directions are easy to find: the east will be on the right, the south behind, and the west on the left. So, guided by the stars, in Russia in the Middle Ages they built roads Moscow - Yaroslavl and Moscow - Vladimir, straight as an arrow.
Secrets of the constellation Ursa Major: how different peoples saw it
Egypt "Bull's Thigh"
The ancient Egyptians were among the first astronomers in history, with some of their round stone "observatories" dating as far back as the fifth millennium BC. It was the Egyptians who laid the foundations of the system of constellations that the inhabitants of Mesopotamia, Greeks, Arabs, and then borrowed from them. modern science. In that dizzyingly distant time due to precession earth's axis it was not the Pole Star that pointed north, but the Alpha Dragon (Tuban). Its environs, together with the nearest luminaries, were considered by the Egyptians to be the "fixed sky", the dwelling place of the gods. Instead of a ladle, the priests could see the leg of Set, the god of war and death, who turned into a bull and killed Osiris with a blow of a hoof. Falcon-headed Horus cut off his limb in retaliation for the murder of his father.
China "Emperor Shandi Carriage"
Astronomers Ancient China divided the sky into 28 vertical sectors, "houses" through which the Moon passes in its monthly journey, as the Sun in its annual rotation passes through the signs of the Zodiac in Western astrology, which borrowed the 12-sector division from the Egyptians. In the center of heaven, like the emperor in the capital of the state, the Chinese had the North Star, which had already taken its usual place by that time. The seven brightest stars of Ursa Major are in honorable proximity to it, within the Purple Fence - one of the three Fences surrounding the palace of the "royal" star. They could be described as the Northern Dipper, whose orientation corresponds to the season, or as part of the carriage of the Heavenly Emperor Shandi.
India "Seven Wise Men"
Observational astronomy in ancient India did not develop as brilliantly as, say, mathematics. Her ideas were greatly influenced by both Greece and China - for example, 27-28 "stays" (nakshatras) through which the Moon passes in about a month are very reminiscent of Chinese lunar "houses". Hindus also gave great importance The North Star, which, according to experts in the Vedas, is the abode of Vishnu himself. The asterism of the Bucket located under it was considered the Saptarishas - the seven sages born from the mind of Brahma, the forefathers of the world of our era (Kali Yuga) and all those living in it.
Greece "Bear"
Ursa Major is one of the 48 constellations listed in Ptolemy's star catalog around 140 BC, although it was first mentioned much earlier, in Homer. Intricate Greek myths offer different backgrounds for its appearance, although everyone agrees that the bear is the beautiful Callisto, the companion of the hunting goddess Artemis. According to one version, using his usual tricks with reincarnation, the loving Zeus seduced her, provoking the wrath of both his wife Hera and Artemis herself. Saving his mistress, the Thunderer turned her into a bear, who wandered in the mountain forests for many years, until her own son, born of Zeus, met her on a hunt. The supreme god had to intervene once again. Preventing matricide, he raised both to heaven.
America "Great Bear"
It seems that the Indians understood something about wild animals: in the legend of the Iroquois about the origin of asterism, the “heavenly bear” does not have any tail. The three stars that form the handle of the ladle are three hunters chasing the beast: Aliot draws a bow with an arrow embedded in it, Mizar carries a cauldron for cooking meat (Alkor), and Benetnash carries an armful of brushwood to kindle the hearth. In autumn, when the Bucket turns and sinks low to the horizon, the blood from the wounded bear drips down, painting the trees in variegated colors.
- The closest of the bright stars of Ursa Major– star Southern Alula or xi Ursa Major. This is a beautiful double star that can be separated into components in a telescope with a lens over 80mm. Both components are similar in their characteristics to the Sun and each of them also has a satellite - a cold red dwarf! The distance to ξ Ursa Major is 29 St. years. A little further away is the star θ - 44 light years from the Sun. Well, farthest from all the bright stars of the constellation is the red giant μ Ursa Major, one of the stars in the front "paw" of the Ursa. Its distance is 249 light years.
- The constellation Ursa Major is depicted on the flag of Alaska. On the flag of the White Sea Karelia, which was approved on June 21, 1918, the Big Bucket is depicted. Also, the flag with the image of the Big Dipper is used by Irish radical left organizations.
- Ursa Major can be admired during the day. This can easily be done by finding it on one of interactive maps constellations. On the maps, you can find other large and small constellations and look at them in a big approximation.
- Needless to say, the huge constellation Ursa Major is a real treasure trove for a true astronomy lover?! In this area of the sky there is a huge number of attractions available for observation in small telescopes: double and variable stars, several bright galaxies and dozens of weaker galaxies, an open star cluster and even a planetary nebula. There is no way to fit the descriptions of these objects into the scope of one article. Therefore, we decided to publish separate articles on observations of the sights of the Big Dipper.
The most noticeable and well-known constellation to all, without exception, is, of course, Ursa Major. Rather, it is not she herself that is clearly visible in the night sky, but part of her - the Big Dipper. If you look closely, then below and to the right of it you can see a few more stars that make up the paws and head of the Bear. The shape of this constellation is really very interesting. After all, no one has ever seen bears with such long tails.
The most visible part of the constellation
The number of bright stars in the Big Dipper bucket is known to everyone. There are exactly seven of them. The name of these stars was given by Arab astronomers in the Middle Ages. To our ears, their “names” sound really strange:
- Merak.
- Mizar.
- Fegda.
- Megrets.
- Dubge.
- Aliot.
- Benetnash.
From the earth, these stars appear equidistant. In fact, this is far from the case. The number of bright stars in the Ursa Major bucket is seven, and all of them are not at equal distances from the Earth and the Sun.
Closest to our planet is Benetnash. Before - Aliot - sixty Nevertheless, she looks brighter than Benetnash. This is the brightest and most brilliant object of the Bucket. According to the apparent intensity of the emitted light, all the stars of this part of the Big Dipper are close to stars of the second magnitude.
If you look very closely at one of the stars of the Bucket - Mizar, you can notice a faint flicker right next to it. This is explained very simply. Mizar is not an ordinary star, but a double one.
The facility located right next to it is called Alcor. From Arabic, these two words are translated as "Horse" and "Rider". Alcor and Mizar are one of the most visible double stars from Earth.
The number of bright stars in the Big Dipper bucket is seven. However, if you look at it through binoculars or a telescope, you can see two more small strokes of light. Unlike stars, they look fuzzy and blurry. This is what distant galaxies look like from Earth. Located in the inside of the Ursa are called Whirlpool and Pinwheel.
Rotation of the Big Dipper
The fact that our Earth does not stand still is known to any schoolchild. Due to its movement, it seems that the stars in the sky rotate. The Bucket is no exception in this regard. In winter and autumn, Ursa Major is located in the northern part of the night sky, not too high from the horizon. In spring and summer, this most noticeable constellation can be seen almost at its zenith. And at this time of the year, Ursa Major looks upside down.
celestial compass
So, the number of bright stars in the Big Dipper bucket is exactly seven. Two of them can serve as a guide for those who are on the road. The fact is that it is easy to detect the most famous star in the world - the Polaris. It's easy to do. It is only necessary to draw an imaginary line along the two outer stars of the Ladle bowl. Next, it should measure approximately the distance between them. The North Star itself is located almost above the northernmost pole.
In ancient times, when there were no navigational instruments, it served as a guide for all sailors and travelers. So, if you suddenly find yourself in a difficult situation in an unfamiliar area - look at the constellation Ursa Major. The polar star found on it will show you the way to the north. This small and not too bright celestial object has more than once rescued those who got lost in the taiga, in the desert or in the sea. The North Star leads the nearest neighbor of the Big Dipper - the Little Dipper. The location of both of these "animals" is considered circumpolar according to the classification of astronomers.
How many stars are in the Big Dipper
Of course, there is much more to this than in its most noticeable part - the Bucket. At the moment, about 125 of them are known. These are over a hundred bright objects, against which the Sun would look like a small and dim luminous dot. The closest star to Earth, unfortunately, is not even visible to the naked eye. She also does not have a name. According to astronomical classification, it passes as a 7.5 m star. The light from it to the Earth takes about 8.25 years. This is almost twice as much as from the closest star to us - Alpha Centauri. Thus, the answer to the question of how many stars are in Ursa Major is simple - more than a hundred and not all of them are visible without a telescope or binoculars. To see a wild animal with a long tail in the Bucket, in fact, you need to have a fairly rich imagination.
Legend of the Big Dipper
Of course, about such noticeable objects of the night sky as the stars of the constellation Ursa Major, there simply cannot but exist many different kinds of myths and legends. The most famous legend about her was invented by the Greeks. The chroniclers of this ancient country say that once the king of Arcadia had an unusually beautiful daughter, Callisto. And this girl was so proud of her attractiveness that she dared to compete with Hera herself, the wife of Zeus. The enraged goddess, using her mystical power, of course, took revenge on the proud woman, turning her into a bear. The son of Callisto Arcas, who was returning from hunting at that time, saw a wild beast at the door of the palace and decided to kill him. However, at the last moment he was stopped by Zeus, who was not indifferent to the beauty. After the rescue, Callisto was raised to heaven. The stars of the Ursa Major bucket are what it is. At the same time, the supreme god raised the beauty’s beloved dog to heaven. Now it is known under the name of Ursa Minor.
nearest constellations
The stars in the constellation Ursa Major, or rather in its Bucket, are the most visible in the night sky. However, in addition to Ursa Minor, there are several other well-known constellations in the area. The reference point for finding one of them can be the same Polar Star. Behind her, on the opposite side from the Big Dipper, at approximately the same distance, Cassiopeia, familiar to many by name, flaunts. Outwardly similar to the Russian letter "M". At some positions of the Earth, Cassiopeia "turns over" and takes the form of a Latin W.
Between it and Ursa Minor, one can see not so noticeable, but also notorious, it does not have a clearly visible form. Between Ursa Major and Ursa Minor, it is also easy to see a wriggling Dragon. The chain of its stars is easily connected on the map by a broken line.
Well, we hope we have answered the main question of the article about how many luminous permanent objects there are in Ursa Major. There are only seven of them in the Bucket. The main constellation includes about 125 distant "suns".
> Ursa Major
| An object | Designation | Meaning of the name | Object type | magnitude |
| 1 | M40 | Not | double star | 8.40 |
| 2 | M81 | Bode Galaxy | spiral galaxy | 6.90 |
| 3 | M82 | Cigar | barred spiral galaxy | 8.40 |
| 4 | M97 | Owl Nebula | planetary nebula | 9.90 |
| 5 | M101 | pinwheel | spiral galaxy | 7.90 |
| 6 | M108 | Not | spiral galaxy | 10.00 |
| 7 | M109 | Not | spiral galaxy | 9.80 |
| 8 | Aliot | "Black Horse" | Blue and white subdwarf | 1.77 |
| 9 | Dubhe | "Big Bear's Back" | Blue and white subdwarf | 1.79 |
| 10 | Benetnash | "Leader of the Wailers" | blue subgiant | 1.86 |
| 11 | Mizar | "Belt" | blue subgiant | 2.27 |
| 12 | Merak | "Groin" | blue subgiant | 2.37 |
| 13 | Fekda | "Bear's Thigh" | blue subgiant | 2.44 |
| 14 | Psi Ursa Major | Not | orange giant | 3.01 |
| 15 | Iota Ursa Major | "Third Northern" | Blue subdwarf | 3.14 |
| 16 | Theta Ursa Major | Not | Double star system | 3.17 |
| 17 | Megrets | "The base of the tail" | blue subgiant | 3.31 |
| 18 | Omicron Ursa Major | "Bear face" | double star | 3.35 |
| 19 | Lambda Ursa Major | "Second North" | Blue subdwarf | 3.45 |
| 20 | Nude Ursa Major | "First Northern" | orange giant | 3.48 |
| 21 | Mu Ursa Major | "Second South" | blue subgiant | 3.57 |
| 22 | Kappa Ursa Major | Not | Double star system | 3.60 |
| 23 | X Ursa Major | Not | orange giant | 3.69 |
| 24 | Upsilon Ursa Major | Not | Double star system | 3.78 |
| 25 | Xi Ursa Major | "First South" | Double star system | 3.79 |
| 26 | Alcor | "Forgotten" | blue subgiant | 4.01 |
How to find constellation Ursa Major in the northern sky: a map of the starry sky, a description with a photo and a diagram, myth, facts, Messier objects, main stars, the Big Dipper.
Ursa Major - constellation, which is located in the northern sky and from Latin "Ursa Major" is translated as "big bear".
Ursa Major in the sky is the largest northern constellation and the third in the general list. Bright stars create an asterism recognizable by all - the Big Dipper, a photo of which can be found on the site. He was known in many cultures, so many myths were created. In the second century, Ptolemy cataloged it.
Myth, facts, position and map of the constellation Ursa Major
Ursa Major is not only a large, but also a very ancient constellation, which was mentioned by Homer in the Bible. There are so many stories and fairy tales around the world. The ancient Greeks believed that we are talking about Callisto - a beautiful nymph who took a vow of celibacy in the temple of Artemis. But Zeus fell in love with her, seduced her and her son Arkas appeared.
When Artemis found out about this, she drove Callisto away. But then the angry Hera (wife of Zeus) came into play. She was so offended by the betrayal that she turned the nymph into a bear. In this guise, the girl spent 15 years living in the forest and hiding from hunters. But Arkas grew up and one day they collided. Arkas was frightened and pulled out a spear, but Zeus managed in time and sent both of them into the sky with a whirlwind. Of course, this angered Hera even more. She asked the Ocean and Tethys not to let the bear swim in the northern waters. That is why Ursa Major never sets beyond the horizon in northern latitudes.
According to another story, the punishment came from Artemis. After many years, Callisto and Arkas are captured together and go to King Lycaon as a gift. But they escape and hide in the temple of Zeus. God saves them and sends them to heaven.
There is also a completely different myth about Adastreya. She was a nymph who took care of Zeus as an infant. His father Cronus obeyed the oracle's prediction (the child will overthrow the father) and killed all his children. But Rhea (mother) slipped a stone instead of Zeus and saved the baby. Adastraya, along with Ida, fed and looked after him, and in gratitude he sent them to heaven.
The Romans called the constellation Ursa Major "Septentrio" - "seven plows of oxen", although only two of them displayed bulls, and the rest - a cart. In the Big Dipper they saw different animals: a camel, a shark, a skunk, as well as objects: a sickle, a cart, a canoe. The Chinese name the 7 stars Qiyh Sing after the government. The Hindus had 7 wise men, and the constellation is called Saptarshi.
In some Indian tales, Ursa Major depicted a large bear, and the stars were warriors who declared a hunt for him. It drops low in autumn, so it is believed that the leaves turn red due to blood dripping from the wounds of the animal.
In late American history, the constellation represented the railroad that the slaves used to find their way north. There are many songs that the liberated sang in the south, dreaming of a new life.
Facts, position and map of the constellation Ursa Major
With an area of 1280 square degrees, the constellation Ursa Major is in third place in terms of size. Covers the second quadrant in the northern hemisphere (NQ2). Can be found in latitudes from +90° to -30°. Adjacent to , and .
| Big Dipper | |
|---|---|
| Lat. title | Ursa Major |
| Reduction | UMa |
| Symbol | Big Dipper |
| right ascension | from 7 h 58 m to 14 h 25 m |
| declination | from +29° to +73° 30’ |
| Square | 1280 sq. degrees (3rd place) |
| brightest stars (value< 3 m ) |
|
| meteor showers |
|
| neighboring constellations |
|
| The constellation is visible at latitudes from +90° to -16°. The best time for observation is March. |
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The main stars of the constellation Ursa Major
You could see in the photo what the constellation Ursa Major looks like in the sky, but let's study its stars and the famous asterism.
Asterism - Big Dipper
The Big Dipper is one of the most recognizable asterisms in the night sky and has been featured in many cultures. In addition, it is also useful in navigation, because it indicates the path to the North Star, which is part of the Little Dipper (Ursa Minor).
If you follow an imaginary line from Merak to Dubhe and continue the arc, you will reach the Pole Star.
In the same way, an imaginary line leads to the bright star Arcturus (Boötes) and Spica (Virgo).
Ursa Major consists of 7 stars: Dubhe (Alpha), Merak (Beta), Fekda (Gamma), Megrets (Delta), Aliot (Epsilon), Mizar (Zeta) and Alkaid (Eta).
Aliot(Epsilon Ursa Major) is the brightest star in the constellation (A0pCr) with an apparent visual magnitude of 1.76 and a distance of 81 light years. It stands at the 31st position in brightness among all stars. The spectrum resembles a Canis Alpha-2 type variable with fluctuations in spectral lines of 5.1 days.
Included in the Ursa Major Moving Group of Stars (general speed and origin). In 1869, the group was found by the English astronomer Richard A. Proctor, who guessed that all the stars of the constellation, except for Alkaid and Dubhe, share a common regular movement, heading towards a point in the constellation Sagittarius.
The traditional name comes from the Arabic word alyat - "fat tail of a sheep" (the star is in a bear's tail).
Dubhe(Alpha Ursa Major) is a spectroscopic double star (K1 II-III) with an apparent magnitude of 1.79 and a distance of 123 light years. The companion is a main sequence star (F0 V) with an orbital period of 44.4 years at a distance of 23 AU.
At 900,000 a.u. from the main pair is located binary system, which makes the star a four-star system.
The name comes from the Arabic dubb - "bear". Not included in the Ursa Major Moving Group of Stars.
Merak(Beta Ursa Major) is a main sequence star (A1 V) with a visual magnitude of 2.37 and a distance of 79.7 light years. There is a dusty disk that occupies 27% of the earth's mass.
The star is 2.7 times more massive than the Sun, 2.84 times larger in radius, and 68 times brighter. It is a member of the Ursa Major Moving Group of Stars and is a suspected variable star.
The name is translated from Arabic as "loins".
Alkaid(Eta Ursa Major) is a young main sequence star (B3 V) with an apparent visual magnitude of 1.85 and a distance of 101 light years. It ranks third in brightness in the constellation and 35th among all stars. It is the easternmost star in the asterism. At a surface temperature of 20,000 K, it can be seen with the naked eye. Reaches 6 solar masses and is 700 times brighter. Does not belong to the Ursa Major Moving Group of Stars.
Despite its position in brightness, Bayer named it "Eta" because he named the stars from west to east. The name is taken from the Arabic phrase qā "id bināt na" sh, which means "leader of the daughters of the pier."
Fekda(Gamma Ursa Major) is a main sequence star (A0 Ve) with a visual magnitude of 2.438 and a distance of 83.2 light years. It has a gas envelope that adds emission lines to its spectrum. Age - 300 million years. It is the lower left star in the Dipper and is 8.5 light-years distant from the Mizar-Alcor system. Refers to the Moving Group of Ursa Major.
The traditional name comes from the Arabic phrase fakhð ad-dubb, "bear's thigh".
Megrets(Delta Ursa Major) is a main sequence star (A3 V) with a visual magnitude of 3.312 and a distance of 58.4 light years. 63% more solar mass and 14 times brighter. There is an excess of infrared radiation, indicating disk debris in orbit.
Of the 7 bright stars, this is the weakest. "Megrets" is translated from Arabic as "base" (the base of the bear's tail).
Mizar(Zeta Ursa Major) - a system of two double stars, located in second place from the end. The apparent magnitude is 2.23, and the distance is 82.8 light years. Became the first photographed double star. It happened in 1857 thanks to the American photographer and inventor John A. Whipple and the astronomer George P. Bond. They used a wet collodion plate and a 15-inch refractor telescope at the Harvard College Observatory. Bond also photographed the star Vega (Lyra) in 1850.
The name comes from the Arabic mīzar - "belt".
Alcor(80 Ursa Major) - visual companion for Mizar (A5V) Both stars are sometimes referred to as "Horse and Rider". The visual magnitude is 3.99, and the distance is 81.7 light years. She is also called Suha ("forgotten") and Arundhati in India. In 2009, they found a binary system.
Belongs to the Moving group of stars Ursa Major. The distance between it and Mizar is 1.1 light years.
W Ursa Major is a binary system represented by nearby stars with an orbital period of 0.3336 days. They are so close that their outer shells are in direct contact. Periodically, they outshine each other, and reduce the brightness. The apparent magnitude of the system fluctuates between 7.75 and 8.48. Spectral class - F8V.
This is the prototype for both the W variables of Ursa Major.
Messier 40(M40, Winnecke 4, WNC 4) is a binary star with fluctuations in apparent visual magnitude from 9.55 to 10.10. Located 510 light years away. It was registered in 1764 by Charles Messier, who was looking for a nebula previously reported by Jan Hevelius. In 1863, the star was discovered by Friedrich August Theodor Winnecke.
47 Ursa Major- a main sequence star (G1V) with an apparent magnitude of 5.03 and a distance of 45.9 light years. It is a solar analogue with a similar mass, slightly hotter and reaches 110% iron.
In 1996, a planet 2.53 times the size of Jupiter was found. Two more planets were discovered in 2002 and 2010.
Nu and Xi Ursa Major - "first jump"
Alula Northern (Nu Ursa Major) is a double star visible to the naked eye. The apparent magnitude is 3.490, and the distance is 399 light years. This is a giant (K3 III), whose radius is 57 times greater than the sun and 775 times brighter. The name "Alula Borealis" comes from the Arabic word al-Ūlā - meaning "first (jump)", and the Latin "Borealis" - northern.
Alula South (Xi Ursa Major) is a star system discovered in 1780 by William Herschel. It is represented by main sequence dwarfs (G0 Ve) with a combined magnitude of 3.79 (4.32 and 4.84), and a distance of 29 light years.
This is a variable star RS Canis Venichi (near binary stars with large spots created by the active chromosphere). Spots cause the brightness to change by 0.2 magnitudes.
Each of the two objects of the Xi system acts as a spectroscopic twin and is accompanied by a low-mass companion. In 1828, Xi became the first binary star whose orbit could be calculated.
Nu and Xi are the first of three star pairs, which the ancient Arabs called "gazelle jumps".
Taniya North (Lambda) and Taniya South (Mu) - "second jump"
Lambda Ursa Major is a star (A2 IV - losing mass and turning into a giant) with an apparent magnitude of 3.45 and a distance of 138 light years.
Mu Ursa Major is a red giant (M0) located 230 light years away. The visual magnitude is 3.06. It is a semi-regular variable star whose brightness ranges from 2.99 to 3.33. Accompanied by a visual companion 1.5 AU distant.
Talita North (Iota) and Talita South (Kappa) - "the third jump"
Iota Ursa Major is a star system represented by two double stars: white subgiant (A7 IV), which is a spectroscopic binary object, and stars of 9th and 10th magnitude. When the B component was noticed in 1841, the two binary stars were separated by 10.7 arcseconds. Now this distance is 4.5 arc seconds. The orbital period is 818 years. The system is 47.3 light years distant from us.
Kappa Ursa Major is a double star represented by two A-type main sequence dwarfs with visual magnitudes of 4.2 and 4.4. The apparent magnitude of the system is 3.60, and the distance is 358 light years.
Muscida(Omicron Ursa Major) is a multiple star system (G4 II-III - between a giant and a bright giant) with an apparent visual magnitude of 3.35 and a distance of 179 light years. The traditional name means "snout".
Groombridge 1830- subdwarf (G8V), located at 29.7 light years. In the early 19th century, it was found and recorded by the British astronomer Stephen Groombridge (published in 1838).
At the time of discovery, it was the star with the highest proper motion. Went to third after discovering Kapteyn's Star and Barnard's Star.
It is a halo star moving in the opposite direction of the galaxy's rotation. Usually such specimens are poor in metal, because they formed at an earlier age of the galaxy. Most halo stars are located above or below the galactic plane. Age - 10 billion years. They have highly eccentric orbits and high space velocity.
Lalande 21185- a red dwarf (M2V) with an apparent magnitude of 7.520 (cannot be found without technology) and a distance of 8.11 light years. This is the fourth closest star system to ours after Alpha Centauri, Barnard's Star and Wolf 359. In 19900 years, it will approach the Sun at 4.65 light years.
This is the BY Dragon variable and is a known X-ray source.
Psi Ursa Major- an orange giant (K1 III) with a visual magnitude of 3.01 and a distance of 144.5 light years. The Chinese call him Tian Zang or Ta Zun - "extremely honorable."
Celestial objects of the constellation Ursa Major
Bode Galaxy(M81, NGC 3031) is a bright, large spiral galaxy 11.8 light-years away. Apparent magnitude - 6.94 (very popular among beginners and amateur astronomers).
The apparent size is 26.9 x 14.1 arc minutes. In March 1993, a supernova was observed - SN 1993J.
It was discovered by German astronomer Johann Bode in 1774. In 1779, Charles Messier re-identified her and added her to the catalog.
It is the largest galaxy in the M81 group (34 galaxies), located 10 degrees northwest of the star Dubhe (Alpha Ursa Major).
It interacts with the neighboring galaxies Messier 82 and with the smaller NGC 3077. Because of this, all lost hydrogen gas and formed gaseous filamentary structures. In addition, star formation has been activated, caused by interstellar gas entering the centers of Messier 82 and NGC 3077.
Galaxy Cigar(M82, NGC 3034) is an edge galaxy with an apparent magnitude of 8.41 and a distance of 11.5 million light years.
Star formation in the galactic core is 10 times faster than star formation in the entire Milky Way. M82 is also 5 times brighter. In 2005, Hubble found 197 massive star clusters in the central region.
M82 exhibits infrared excess and is the brightest galaxy in the sky when viewed in infrared light.
It is believed to have experienced at least one tidal collision with Messier 81 in the past. Because of this, over the past 200 million years, a huge amount of gas has entered its core and increased star formation by 10 times.
Owl Nebula(M97, NGC 3587) is a planetary nebula with an apparent magnitude of 9.9 and a distance of 2600 light years. In the center is a star of the 16th magnitude.
In 1781, the nebula was discovered by Pierre Méchain. Age - 8000 years. It got its name because it looks like an owl's eye when viewed through a telescope.
pinwheel(M101, NGC 5457) is a grand design spiral galaxy observed by the face. The apparent magnitude is 7.86, and the distance is 20.9 million light years. In August 2011, they found a type Ia supernova (an explosion of a white dwarf star) - SN 2011fe.
Pierre Méchain discovered the galaxy in 1781 and was later added to the catalog by Charles Messier. Méchain described it as "a nebula without a star, very obscure and rather large - from 6" to 7" in diameter".
It covers 170,000 light-years in diameter (70% larger than the Milky Way). Hosts a number of large, bright H II regions and hot newborn stars.
There are 5 companion galaxies: NGC 5474, NGC 5204, NGC 5477, NGC 5585 and Holmberg IV. Most likely, the grand design was created due to contact with them.
(M108, NGC 3556) is a barred spiral galaxy discovered by Pierre Méchain in 1781. We see almost the edge. It has a visual magnitude of 10.7 and a distance of 45,000 light years.
It is an isolated member of the Ursa Major Cluster (within the Virgo Supercluster). M108 contains approximately 290 globular clusters and 83 X-ray sources.
In 1969, a type 2 supernova, 1969B, was observed.
(M109, NGC 3992) is a barred spiral galaxy with an apparent magnitude of 10.6 and a distance of 83.5 million light-years. It is located southeast of Gamma Ursa Major. In 1781, Pierre Mechain found it, and after 2 years Charles Messier added it to the catalog.
In 1956, a type Ia supernova, SN 1956A, was discovered. There are also 3 satellite galaxies: UGC 6923, UGC 6940 and UGC 6969.
It is the brightest galaxy in the M109 group (contains over 50 galaxies).
NGC 5474 is a dwarf galaxy located near M101, with which it interacts. Shows signs of a spiral structure. The visual magnitude is 11.3, and the distance is 22 million light years.
Due to tidal interactions with M101, the disk shifts away from the core and activates star birth. You can explore the constellation Ursa Major more closely by using our online 3D models and telescope. For independent search, a static or moving map of the starry sky is suitable.
