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| An object | Designation | Meaning of the name | Object type | Magnitude |
| 1 | M77 | No | Spiral galaxy | 8.90 |
| 2 | Difda (Beta Ceti) | "Frog" | Orange giant | 2.02 |
| 3 | Menkar (Alpha Ceti) | "Nose" | Red giant | 2.53 |
| 4 | This Kita | "Southern Whale Tail" | Orange giant | 3.45 |
| 5 | Gamma Ceti | Short hand | Multiple star system | 3.47 |
| 6 | Mira | "Wonderful" | Double star | 3.50 |
| 7 | Tau Ceti | No | Yellow dwarf | 3.50 |
| 8 | Shemali (Iota Ceti) | "Northern Whale Tail" | Orange giant | 3.56 |
| 9 | Theta Ceti | No | Orange giant | 3.60 |
| 10 | Zeta Ceti | "Belly of the Whale" | Orange giant | 3.74 |
| 11 | Upsilon Kita | No | Orange giant | 3.99 |
| 12 | Delta Whale | No | Blue-white subgiant | 4.08 |
| 13 | Mu Kita | No | Double star | 4.27 |
| 14 | Xi-2 Kita | No | White-blue giant | 4.28 |
| 15 | Lambda Kita | No | White-blue giant | 4.67 |
Consider the great equatorial constellation Cetus next to Aquarius, Eridanus and Pisces: description with photos, interesting facts, history, myth, bright stars and objects.
Whale - constellation, which is located in the northern sky and is one of the largest constellations.
The original name Cetus is the name of a sea monster from the Ancient Greek myth of Andromeda. She was sacrificed to a monster to save her father’s kingdom (due to the fault of Cassiopeia, her mother). The whale is located in the celestial area called Water, where other constellations with a water association are collected: (river), (water bearer), etc. Recorded in the second century by Ptolemy.
The constellation Cetus contains a spiral galaxy and several notable stars: Beta Ceti, Menkar, Tau Ceti and the famous variable star Mira.
Facts, position and map of the constellation Cetus
With an area of 1231 square degrees, the constellation Cetus ranks fourth in size. Located in the first quadrant of the southern hemisphere (SQ1). It can be found at latitudes from +70° to -90°. Adjacent to , and .
| Whale | |
|---|---|
| Lat. Name | Cetus |
| Reduction | Set |
| Symbol | Whale |
| Right ascension | from 23 h 50 m to 3 h 17 m |
| Declension | from -25° 30’ to +9° 55’ |
| Square | 1231 sq. degrees (4th 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 +65° to -80°. The best time for observation is October. |
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Whale contains 14 stars with planets and Messier 77 (M77, NGC 1068). The brightest star is Beta Ceti. It also has three meteor showers: the October Cetides, the Eta Cetis and the Omicron Cetis. Included in the Perseus group along with, and. Consider the diagram of the constellation Cetus on a star chart.
The myth of the constellation Cetus
Whale is a sea monster. Because of Cassiopeia's boasting, the Nerids were offended. They asked Poseidon for revenge and he sent the monster Cetus to the kingdom of Cepheus (her husband). The oracle advised to sacrifice her daughter and Andromeda was chained to a rock.
Andromeda was waiting for death, but Perseus passed by, who saved her just at the moment when Cetus was about to have lunch. The hero killed the monster and married Andromeda. Usually the constellation was depicted as a hybrid. It had forelimbs, a huge mouth and a body covered with scales, like a prehistoric snake. Although the constellation was called a whale, there is no similarity in appearance.
The main stars of the constellation Cetus
Explore descriptions, characteristics and interesting facts about the bright stars of the Cetus constellation.
Deneb Kaitos(Difda, Beta Ceti) is an orange giant, spectral type K0 III. It is now in the process of transforming into a red giant. With a surface temperature of 4800 K, the star is slightly cooler than the Sun. It is the brightest in the constellation. The apparent visual magnitude is 2.04, and the distance is 96.3 light years.
It has traditional names. Deneb Kaitos comes from the Arabic phrase Al-Dhanab al-Shayon al-Janubi - "southern tail of the whale", and Difda from aḍ-ḍafda"aṯ-āānī - "second frog" (the star formation in Southern Pisces is called the first).
Menkar(Alpha Ceti) is an incredibly ancient red giant, 249 light years away. It is now pushing out its outer layers and forming a planetary nebula, leaving behind a large white dwarf. Apparent visual magnitude – 2.54. Menkar means "nostrils" in Arabic. Very often the star is used in science fiction. For example, in the Star Trek film series.
Mira(Omicron Ceti) is a double star represented by a red giant and a satellite. The system is 420 light years away.
Mira A is a red giant, spectral type M7 IIIe. This is an oscillating variable star, serving as a prototype for Mira-type variables. This group includes 6,000-7,000 known stars. These are red giants whose surface fluctuations cause changes in brightness with a periodicity of 80-1000 days.
Mira is the first non-supernova found, with the possible exception of Algol in the constellation Perseus, which was only confirmed as a variable in 1667. Mira may be 6 billion years old.
Mira B is a hot white dwarf that is sucking mass from a red giant. They form a symbiotic pair, closest to the Sun.
Mira is the brightest periodic variable star that cannot be seen without special equipment at certain stages of its cycle. The rotation period takes 332 days.
The presence of variability was first described by the German astronomer David Fabricius in 1596. He considered it new until he saw it again in 1609. But officially this merit is attributed to astronomer Johannes Holwerd, who determines the variation cycle of the star.
It received its name from the Polish astronomer Jan Hevelius, which is translated from Latin as “wonderful”. The star produces a trail of material. NASA's Galaxy Evolution Explorer space telescope captured a tail 13 light years long.
Tau Ceti– a cold G-type dwarf (G8.5) with an apparent magnitude of 3.5. This is one of the closest stars to our system, 11.9 light years away. Its mass reaches 78% solar. This makes it one of the few stars that is less massive than our star but is still visible to the naked eye. It has a low level of metallicity. Its luminosity reaches only 55% of the Sun.
Tau Ceti and Epsilon Eridani were two nearby Sun-like stars. In 1960, they were selected as test subjects for the SETI experiment to search for extraterrestrial life. Of course, we did not get any positive results.
Celestial objects of the constellation Cetus
(M77, NGC 1068) is a barred spiral galaxy. It is 47 million light years distant and 170,000 light years in diameter. Apparent visual magnitude – 9.6. It is one of the largest galaxies in the Messier catalogue.
Found in 1780 by French astronomer Pierre Mechain. It was cataloged by Charles Messier. Méchain initially viewed the object as a nebula, while Messier and William Herschel described it as a star cluster. Found 0.7 degrees east-southeast of Delta Ceti (magnitude 4).
Contains an active galactic nucleus hidden by intergalactic dust. This is the strongest radio source, first discovered by Bernard Yarnton Mills. He designated the object as Whale A.
NGC 1055- a spiral galaxy (edge turned towards us) 52 million light years away. Found by William Herschel in 1783. Located just 0.5 degrees north-northeast of Messier 77.
Together with Messier 77, NGC 1055 serves as the largest member of a galactic group that also includes NGC 1073 and several smaller irregular galaxies. It is 115,800 light years in diameter. The galaxy is a known radio source.
NGC 1087– an intermediate spiral galaxy 80 million light years away. It is represented by a small central band, a tiny core and a number of irregular elements on the surrounding disk of material. It is located close to NGC 1090 (a barred spiral galaxy), but they do not interact.
- galaxy in Cetus. Believed to have an H II nucleus. Apparent magnitude - 11.5.
When there are no clouds in the sky and there is a moonless night, more than a hundred stars can be seen in the constellation Cetus. Only nine of them are very bright (brighter than the fourth magnitude) and are included in the outlines of the constellation, creating a long noticeable chain. The constellation Cetus begins in the east with a large oblong polygon, and in the west ends with a large triangle.
In the center of the constellation, a broken line is clearly visible, which is drawn thanks to the brightest stars. For this reason, the whale has always been depicted as a monster with a curved tail and a wide open mouth.
Some of the brightest luminaries that make up the constellation Cetus are Alpha Ceti and Beta Ceti. They are also called Menkar and Difda.
Mira
The comet-like shape of Mira, photographed in the UV range
The most interesting star is an object called Mira. It gave the name to a whole class of variable stars - “Mirids”. The interesting thing about Mira is its variable brightness with a duration of 331.65 days.
Animation of the flight of the Mira star in space
During this time, it changes its glow from the most noticeable star in brightness from 2.0m to 10m - turning out to be so dim that it cannot even be seen with binoculars.
Omicron of China or World. The flow of matter (“tail” on the right) to an invisible companion is visible
When they noticed her, they were very surprised that she was not on the map. Only after half a century of observations did it become clear that this is a long-period variable. As observations and studies have shown, Mira is a red giant with a very low surface temperature (about 2000K)
It is worth paying attention to another variable star - Tau Ceti. It is the 17th smallest from Earth, with characteristics that are very similar to our Sun. For this reason, Tau Ceti is often mentioned in science fiction.
Recently there have been places around it on which intelligent life is quite possible. Telescopes were directed towards it, in the hope of catching an extraterrestrial signal sent by intelligent beings, but so far all in vain.
UV China
There is another variable in the constellation that can change its brightness by five magnitudes! This is UV China. After such outbreaks, it quickly weakens. There is a possibility that the flares on UV Whale are very similar to the flares that occur on our Sun. Only explosions on the Sun are not so large-scale.
Notable is the star HD 11964, which has three exoplanets. This star is approximately 110 light years away. Therefore it is not visible to the naked eye.
Galaxies and other objects
The radiant of the Cetis meteor shower is located near a star called δ Ceti. This radiant is observed in October. It is a weak shower by nature and even at its maximum only a few meteors are observed per hour. But there are also activity spikes of up to 100 meteors per hour.
If you look closely in the constellation, you can see a prominent spiral galaxy called M77.
Journey to the M77 galaxy
Story
If you delve into mythology, then in the constellation there is a monster that was sent by Poseidon to eat the beautiful Andromeda, who was chained to a rock. This monster never dealt with Andromeda and was killed by Perseus.
| List of winter sky constellations | |
|---|---|
The constellation Cetus is one of the largest in the sky. It includes exactly 100 stars visible to the naked eye. Which one is the brightest? The question seems to be very simple, but the answer to it is not entirely usual - “depending on when.” Yes, at different points in time the question posed allows for different answers. And the secret of this strange position is that the brightest (sometimes) star in the constellation Cetus is also a variable star.
This was first noticed by Galileo’s contemporary and one of the best observers of that era, the German David Fabritius. The discovery happened completely by accident. On the morning of August 13, 1596, Fabricius was observing Mercury. There were no telescopes at that time, and Fabricius was going to measure the angular distance from the planet to the star 3m from the constellation Cetus. He had never seen this star before; he did not find it on star maps or star globes of that time. However, both of them were inaccurate, and the omission of some not very bright star was no exception. Nevertheless, being a very careful observer, Fabricius began to follow the unfamiliar star. By the end of August its brightness increased to 2m, but then in September the star faded, and in mid-October it completely disappeared. Fully confident that this was a new star, similar to the one observed by Tycho Brahe in 1572, Fabricius stopped observing. Imagine Fabricius’ surprise when thirteen years later, in 1609, he saw the amazing star again!
By the middle of the 17th century. It was finally established that the mysterious star from the constellation Cetus is a variable star with a very long period of change in brightness and a large amplitude. Thus, for the first time in Europe, a variable star was discovered in the full sense of the word, heading a special class of long-period variable stars. Hevelius also called the extraordinary star from the constellation Cetus “Amazing” or “Wonderful” (in Latin “Myra”). It's safe to say that Mira's physical properties fully justify its name. Mira Ceti (omicron Ceti) varies its brightness from 3.4m to 9.3m. In other words, at maximum brightness it is one of the brightest stars in the constellation, but at minimum it is inaccessible even to good binoculars.
Let us make a reservation that we indicated the average brightness values of Mira at the moments of maximum and minimum. Sometimes Mira becomes a 2.0m star, that is, the brightest star in the constellation Cetus. It also happens that at minimum brightness it weakens to 10.1m. The period does not remain constant - only on average it is 331.62 days. The shape of the light curve also changes noticeably from period to period. This variability makes Mira and other long-period variables different from Cepheids, with their almost stable periods and light curves.
Both Mira and all other variables of the same type without exception are cold red giants with a very low surface temperature (about 2300 K). Their atmospheres are so cold that the spectra of long-period variable stars contain abundant absorption bands of various chemical compounds (in particular, titanium and zirconium oxides). These compounds are very sensitive to even small temperature fluctuations, which are immediately reflected in fluctuations in the intensity of the bands. It is for this reason that fluctuations in the brightness of long-period variables in the visible range of the spectrum have a very large amplitude, while the total radiation of the star varies within much smaller limits.
In the spectrum of Mira and similar stars, during periods of maximum brightness, bright emission lines appear that belong to hydrogen and some metals. At minimum brightness they turn into absorption lines. Long-period variables pulsate, just like Cepheids; this is clearly evidenced by periodic shifts of lines in their spectra.
How can we explain the variability of Mira and other stars of this class? When red giants pulsate, their surface temperature also changes, which immediately affects (this is not the case with hotter Cepheids) the optical properties of their atmospheres. As the temperature rises, chemical compounds decompose and the atmosphere becomes more transparent; as the temperature gets colder, the opposite occurs. A certain role also belongs to those hot hydrogen masses that erupt into the atmosphere during epochs of maximum brightness and further increase the brightness of the star (it is they that give the bright “emission” lines in the spectrum). This is the most plausible explanation for the amazing changes that regularly occur in Mira Ceti. In 1919, it was noticed that Mira’s spectrum was superimposed by a second spectrum belonging to some very hot white star. Four years later, very close to Mira, at a distance of only 0.9", a companion-hot star 10m was discovered. It apparently bypasses the main star in several hundred years. There is a suspicion that this satellite, in turn, is a variable star of an unknown type, the close, in the literal sense of the word, community of two stars that are completely different in physical characteristics, and also variable, is very curious.
We can only be glad that our Sun does not belong to the class of long-period variables. Mira's radiation (in the visible range of the spectrum) changes from maximum to minimum hundreds of times! If solar radiation fluctuated so sharply, it would have a most disastrous effect on the organic world of the Earth. This is unlikely to be why inhabited planets revolve around Mira and similar stars.
In the constellation Cetus, find a bright 3.5m star, about which one can say, perhaps, the completely opposite. This is Tau Ceti, which has become widely known in recent years. It is not difficult to find it on the star map.
Tau Ceti has very fast propulsion. Over the course of a year, it moves in the sky by almost 2". This is a sure sign of the star’s proximity to Earth. Indeed, Tau Ceti is one of the closest stars. The distance to it is only 12 light years. Tau Ceti ~ a yellow dwarf star similar to our Sun , only slightly smaller and colder. The similarity, although incomplete, is manifested in many characteristics, like the Sun, it apparently rotates slowly around its axis (for the Sun, this period is on average close to a month). spectral class A and earlier ones rotate around their axes very quickly, about hundreds of times faster than the Sun, but starting from stars of spectral class F, there is a sharp jump in the direction of decreasing rotation speed. There are serious reasons to think that this jump is caused by the influence of planets. orbiting around cooler stars. These planets, as in our Solar System, took on the lion's share of the total "reserve of momentum" (angular momentum), and therefore the stars around which they orbit have very slow axial rotation.
For all these reasons, it is suspected that Tau Ceti is not only similar in appearance to the Sun, but perhaps inhabited planets are circling around it! This suspicion is so serious that at one time the radio telescopes of American astronomers carefully “listened” to Whale, hoping to receive radio signals from our distant “brothers in mind.” For now, space is silent, but who can guarantee that this immensely daring enterprise will not someday end with a brilliant discovery that creates a completely new era? There is another notable object in the constellation Cetus - the variable star UV Ceti, located not far from the alpha star of this constellation. She leads a special group of flare stars. This dwarf red star of spectral class M5 sometimes in a very short time (several tens of seconds!) increases its brightness from the 13th (usual) to the 7th magnitude; after that its shine slowly diminishes. The return of the star to its normal state takes from 10-20 minutes to several hours. The UV Whale flares themselves repeat on average every 20 hours. Use your binoculars or UV telescope to find a whale and see what condition it is in now. And if possible, track the change in its shine.
About 80 stars of the UV Ceti type are already known in the solar vicinity. Several hundred stars of this type have been found in neighboring star clusters. It is curious that the closest star to us, Proxima Centauri, also belongs to the UV Ceti type stars.
During the outburst, UV Ceti type stars release energy of the order of 10^33 erg. The vicinity of the star UV Ceti At the same time, they emit hot (more than 10,000 K) clouds of gases into the surrounding space. Apparently, such flares are of a similar nature to chromospheric flares on the Sun, differing from them, however, on a much larger scale.
Academician V.A. Ambartsumyan and his supporters believe that flares of UV Ceti type stars are associated with the release of relatively small portions of “prestellar matter” from their depths. There is still too little reliable knowledge on this issue to make final judgments. Based on a number of features, UV Ceti type stars apparently belong to the group of young stars.
One of the most difficult problems of modern natural science is the problem of the origin and evolution of cosmic bodies. Due to the fact that the speed of light is a limited value (300,000 km/s). We always see the Universe in the past, and in the more distant past, the further away the object is from us. For bodies of the Solar System, this effect, of course, does not play a significant role. (For example, we always see the Sun as it was 8 minutes ago.) But for distant star systems, the “lag” in time turns out to be so significant (millions and billions of years) that, moving into the depths of the Universe, we simultaneously penetrate into it distant past. For example, quasars are probably one of the most ancient objects in the Universe. If, in fact, the history of our Universe began 15 billion years ago with the Big Bang, then quasars, 10-12 billion light years away from us, are the primary forms of cosmic matter.