Goes constellation Big Dipper... I'm sure it won't sound loud, that this constellation is the most recognizable in the entire northern hemisphere due to its 7 bright stars, resembling a bucket in shape.
Legend and history
The constellation was named after the nymph Callisto. There are many different legends. One of them has approximately the following content.
According to ancient Greek legend, Zeus saw a beautiful girl, the nymph Callisto, and fell in love with her. Callisto was one of the virgins who accompanied the goddess Diana the hunter. Zeus assumed the form of Diana and became close to Callisto. Seeing this, the real Diana sent her away from her eyes. Hera, the wife of Zeus, having learned about such an act, turned the nymph into a bear. Callisto's son, Arkad, when he grew up, met his mother. But I did not recognize her in the form of a bear. Zeus, fearing that his son would kill his mother, placed both in the sky in the form of the constellations Ursa Major and Ursa Minor. But even in heaven, Callisto did not know peace. Hera begged the gods not to allow the bear to plunge into the ocean. Since then, the nymph-bear has been circling across the sky, without sitting over the horizon.
Ursa Major is one of the most ancient constellations of the starry sky. It has the same name among the Slavs, Indians, Greeks. Included in the catalog of the starry sky by Claudius Ptolemy "Almagest".
The seven stars of the Big Dipper make up the figure that forms the bucket with a handle asterism. But this is only a small part of the constellation itself.
Specifications
| Latin name | Ursa major |
| Reduction | UMa |
| Square | 1280 sq. degrees (3rd place) |
| Right ascension | From 7 h 58 m to 14 h 25 m |
| Declination | From + 29 ° to + 73 ° 30 ′ |
| The brightest stars (< 3 m) | |
| Number of stars brighter than 6 m | 125 |
| Meteor showers |
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| Nearby constellations | |
| Constellation visibility | + 90 ° to −16 ° |
| Hemisphere | North |
| Time for observation on site Belarus, Russia and Ukraine | March |
The most interesting objects to observe in the constellation Ursa Major
Constellation Ursa Major
1. Planetary Nebula "Owl" (M 97)
With a mass of only 0.15 solar, it has a brightness of 9.9 m. It got its name due to the similarity with the eyes of an owl. It can only be found with a professional telescope in good weather conditions. According to scientists, the age is about 6 thousand years. It is located on the bottom of the Big Dipper bowl:
Search for the Owl Planetary Nebula
2. Optical double star M 40
Charles Messier in the 18th century was looking for a nebula that Jan Hevelia had mistakenly described, but in its place he discovered a faint double star. It was decided to enter it into the catalog under serial number 40 ( M 40). These are two stars with a brightness of 9 m and 9.3 m. As calculations show, this is an optically double star, that is, both stars are not related to each other in any way, but are located close along the line of sight. The location in the sky relative to the bucket is shown below:
3. Spiral galaxy M 101
Spiral galaxy popularly M 101 nicknamed "Pinwheel"... Has a brightness of 7.7 m. It will not be possible to observe it through binoculars, due to the weak surface brightness. No matter how hard I tried, it didn't work out. But already in amateur telescopes, you can see the bright central part. The photo shows that M 101 asymmetric: the galactic nucleus is far from the center of the disk. This galaxy is well studied by scientists: they were observed in it in 1909, 1951 and 1970.
It is not difficult to find it in the starry sky, and beginners often begin to practice with it.
Spiral Galaxy "Pinwheel" (M 101)
4. Spiral galaxy M 108
A galaxy that can be found in semi-professional or professional telescopes. As a rule, it is found paired with the planetary nebula "Owl" (2) due to its proximity. Has a brightness of 10.0 m.
5. Spiral galaxy M 109
In some sources, you can find its other name - "Vacuum cleaner"... It is located not far from the Ursa Major gamma, and, despite the fact that it has a brightness of only 9.8 m, you can try to find it with a telescope. M 109 has at least three satellite galaxies of its own. Taking the star Fad (Fekda) as a reference point, we move smoothly and slowly to the west - after a few seconds we are trying to recognize and find the desired galaxy:
M 109 or Galaxy "Vacuum Cleaner"
6. A pair of galaxies M 81 and M 82
Two nearby galaxies M 81 and M 82
Probably the most key objects to observe in the constellation Ursa Major. First, they are not hard to find; secondly, both have an accessible stellar magnitude for observation even with amateur telescopes: 6.9 m and 8.4 m, respectively; thirdly, in close proximity to each other at a low magnification, they can be seen simultaneously in the telescope lens, approximately, as shown in the photo above. An example search route is shown below:
Above the Bode Nebula is the Cigar Galaxy
Considering both galaxies separately, it is worth adding that M 81 or the Bode Nebula is a beautiful spiral galaxy. It deforms its "neighbor" by the gravitational field. Hubble telescope studies 32 variable stars inside M 81.
Galaxy M 82 or "Cigar" has an irregular shape (refers to) and is weaker than M 81... Active star formation is taking place inside it. At the center of the galaxy is a supermassive
In the constellation Ursa Major there is a planetary nebula "Owl", which has long been known to astronomers. It is officially called NGC 3587. It is located about 2 thousand light years from Earth. Her snapshot is shown above. It really does somewhat resemble the physiognomy of an owl (in any case, it has two large "eyes"). This nebula has a rather complex structure, consisting of three shells: a dim outer halo, a globular middle, and an elliptical inner shell. The inner elliptical shell contains two "eyes", as well as a relatively bright "forehead" and "beak".
Astronomers recently presented a model for the evolution of this planetary nebula that explains its shape. This is the subject of an article by an international group of astronomers published in the June issue of the Astronomical Journal.
Planetary nebulae actually have nothing to do with planets, they just looked like planets in medieval telescopes. They represent what remains after the explosion of a star at a certain stage of its development. As a result of observations of the Owl Nebula using ground-based telescopes, astronomers concluded that its halo was formed when that very star, after the termination of a nuclear reaction in its core, for the first time ejected a large part of its matter into space. This cataclysm gave rise to the stellar wind, which together "fanned" the pulsations of the star and the pressure of its radiation.
As a result of the further evolution of the star, the stellar wind became so powerful that huge masses of gas and dust were carried out into space, from which the middle shell was formed. Further, the stellar wind intensified even more and during its interaction with the previously ejected matter, an inner shell was formed - a structure with two "eyes". And then, after the final death of the star, the stellar wind stopped, and the resulting structure began to "deflate", like a balloon deflates if you stop inflating it.
The Owl Nebula M97 (also called NGC 3587) is a planetary nebula located in. It is approximately 2,600 light years (797 parsecs) from Earth.
Opening
The nebula was discovered by the French astronomer Pierre Mechein on February 16, 1781 and was later introduced to Charles Messier as number 97. It is one of the four planetary nebulae included in this catalog (along with M27, M57 and M76). When the British astronomer Lord Ross (William Parsons) observed this nebula in 1848, he sketched it as something to which he called "the head of an owl."
Structure and features
Like most planetary nebulae, Messier 97 is more visible not in the photo, but in optics, since most of the radiation falls on the green part of the spectrum. The nebula's star has an apparent magnitude of 16m and a mass of 0.7 solar masses. The temperature of this white dwarf is 123,000 K.
The gas around the star includes hydrogen, helium, oxygen, nitrogen and sulfur, and is estimated to have a mass of 0.15 solar masses.
Education and disappearance
The Owl Nebula is about 8,000 years old. The once dying star (today the central star M97) used up all its hydrogen, as a result of which it passed from the red giant stage to a white dwarf, while pushing out the outer shell. It is noteworthy that during the collapse, the star displaced its material simultaneously in two directions. The jets of this material coincide with the observation line. For this reason, two dark "eyes" of the nebula appear to the observer.
Today, the scattered shell is heated by radiation from the star, causing it to glow. And although it will take several billion years to cool the white dwarf, the nebula itself will dissipate within several thousand years - the expansion rate is 27.39 km / s.
Observations
You can observe the Owl Nebula with 20 x 80 binoculars or a small telescope. In such a tool, the nebula will outwardly resemble a glowing spot. To distinguish the "eyes" of the Messier 97 nebula, a telescope with an aperture of 250 mm or more is required. In the more powerful tool, you can see a reddish halo around the nebula.
Messier 97 is located 2.5 degrees southeast of the star, slightly south of the segment between the stars of the Bucket - Merak and
