The story of the Hyades is highly foggy, like an autumn morning in Greek Boeotia, when the radiance of the predawn stars melts in the rays of the rising Helios, but the clouds floating from the north bring only rain, and not the warmth of the passing summer...
Now no one will remember how many there were — star sisters born from the passionate love of the titan Atlas and the oceanid Aethra. Someone claims that there are only two, but there is a mention of fifteen daughters of the "Holder of Heaven" ... But are all of them Hyades? Of course not. After all, among the daughters of Atlas there were also the Pleiades and Hesperides. They also had a brother, Hyas. It was because of him that the very name of the Hyades arose — mourning about Hyas. Hyas was careless and died hunting. There are at least four culprits for his death — a huge boar, a ferocious lion, an angry lioness, a Libyan snake. His sisters could not come to terms with the loss of Hyas, wept bitterly day and night — so inconsolably that even the sky itself was moved, and began to shed tears along with the Hyades sisters.
Could not keep his compassion and the main Hellenic God — Zeus the Thunderer. He transferred the sisters to the sky, thus creating a beautiful stellar cluster at the head of the Taurus constellation. However, it was not only by their sobbing that the Hyades deserved such a high honor. They also had other accomplishments.
In that old time, when not all the Greek Gods had time to reign on the sacred Olympus, Zeus fell in love with the beautiful Semele, the daughter of Boeotian king Cadmus (the founder of Thebes) and goddess Harmony. Of course, the legal wife of Zeus, Hera, found out about the connection between Zeus and Semele, and decided to teach her rival a lesson.
— What is it like to be in the arms of the greatest of Gods? Is it him, or just his vision? If he has mastered me, let him become mine... — These are the thoughts that began to spin in Semele's head. And on one of the dates, she asked Zeus to swear that she would fulfill any of her requests. It is foolish to ask God to swear on anything. This is not reasonable for humans either. But Zeus did not refuse his beloved, and then she asked to hug her as passionately as he hugs his Hera. Zeus began to refuse, but then he realized that there was no turning back — he swore, and if God does not keep his oaths, then what should people do?
And Zeus flashed with a thousand lightning bolts, thundered, and at the same moment Semele turned into a handful of ashes. But even a moment before that, Zeus managed to save the fetus with which Semele was already pregnant — from Zeus. Zeus placed the cub in his thigh and carried it for another three months until he was born — right from the thigh of Zeus.
Who was it?
God of gardens, vineyards and winemaking — Dionysus — the youngest of the Olympian Gods.
The baby was weak and premature. Plus, he's an orphan. Zeus was clearly not up to the child, but he took care of his son — he gave him to be fed and raised in the Nisei Valley — this is also somewhere in Boeotia — to the local nymphs — to the same Hyades sisters. And this was their main purpose — to educate and feed Dionysus.
But I must say that Dionysus was still a "Surprise", and his nurses were very worn out and aged, while Dionysus was looking for a recipe for a drink of joy and fun — he sometimes got up something stupid so that the sisters Hyades grabbed their heads. But they did not give up on self mission.
When it was time to say goodbye to the hospitable valley of Nisei and go to Olympus, Dionysus suddenly noticed that the once young maidens who raised and raised him had turned into old women — for some reason, the nymphs Hyades were subject to old age. Usually this did not happen with the nymphs, but it happened with the Hyades. And then Dionysus decided to give them a parting gift — he asked the sorceress Medea (whom we remember from the myth of the Argonauts' journey) to give the Hyades sisters the elixir of youth and immortality. And they again became as young as before meeting the baby-Dionysus.
But the Hyades were not ready for eternal life. And when a misfortune happened to their brother Hyas, they began to ask for death in order to go to the kingdom of Hades after their beloved brother.
But Zeus decided to do otherwise — not to fulfill the request of women who are under the influence of strong feelings (somehow he already burned himself on this). And sent the sisters to the Heaven, where they flashed a scattering of stars around the bright star Aldebaran.
There is a superstition that the early morning sunrise of these stars brings a couple of weeks of rain after a hot, dry Greek summer.
Unlike the Pleiades, which in one form or another are present in the cultural heritage of various peoples and eras, the Hyades are not mentioned anywhere except in Greek myths. And even the stars scattered over the face of the "Heavenly Bull" do not have the names of star sisters. But these stars still have some names. They are not very popular, and are of mixed origin.
In particular, Gamma, Delta and Theta Taurus are simply referred to as Hyadum 1, Hyadum 2, Hyadum 3. At the same time, Epsilon Taurus (the top one in the triangle of Hyades) has the Arabic name Ain ("Eye", which strange, since the orange Aldebaran nearby on the star map is also the "Eye"), but in Flamsteed's catalog is referred to as the "Oculus Boreus" ("Northern Eye"), so the anatomy of celestial beings remains still unknown matter. The main thing is that none of the mythological names of the Hyades sisters — the servants of Dionysus — is reflected on the star map. And this is another significant difference in the archaic views on these stellar clusters.
Along with this, mythology has brought to us a huge list of names of the Hyades clan, but I will not dwell on it now. And now I propose to move on to the astronomical part of the story.
First of all, orange Aldebaran must be excluded from the suspects of involvement in the Hyades. Visually, it is located in the central part of the cluster, but is only projected onto it. In reality, Aldebaran is 2.5 times closer — 65 light years. Aldebaran is part of our nearest stellar environment. The Hyades are located much further — 150 light years separates the Sun and the central part of the cluster.
But the cluster itself is huge. It is a stellar swarm about 30 light-years across. And to date, astronomers have identified about 700 stars that are involved in the Hyades — by origin in the first place. Although some stars could be here by accident. But there are probably not many such exceptions. It is possible that the total stellar population of the Hyades exceeds a thousand stars, but some of them are simply invisible from this distance, being brown dwarfs.
At first glance, it may seem that 1000 stars is a lot. But if you calculate, then in the volume of a sphere with a diameter of 30 light years, the average density will be less than less than one star per cubic light year. This is less than the average stellar population density in the spiral arms of our Galaxy.
True, the Hyades are not located in the spiral arm, although they are visible in the sky in the direction of the Perseus-Orion arm. They are much closer, because the Perseus-Orion arm is about 1000 light-years away. And there, the average distance from star to star of 1 light year is considered quite normal. In the Hyades, the average distance between the stars will be one and a half to two light years. This would significantly complicate the colonization of the cluster of one of the developed civilizations of any of the stars of the Hyades, because during their existence the emergence and flourishing of such a civilization is quite likely — the age of the cluster is estimated to be 650 million years.
For open stellar clusters, this is a lot. Usually, open clusters don't live that long. But the Hyades are already ending their life together — according to scientists, in just 30 million years the cluster will finally disintegrate. In fact, it has already collapsed. And what we are seeing now is just a pitiful remnant of its former greatness. And once the Hyades was a much denser and rich stellar cloud. But now, only its central part resembles a kind of cluster — several stars visible to the eye, scattered next to Aldebaran.
In the central part of the cluster, the stars are still more crowded — here it is only about 1 light year to fly from star to star. But, the cluster is decaying much faster than modern starships fly.
I will inform you that in the region of the Galaxy where the Sun is located, the stars are even rarer — here the average distance between stars is about 6-7 light years.
There are many interesting objects among the stars of the Hyades cluster.
Amateur astronomers note two wide pairs:
- Theta 1 + Theta 2 (referred to as Hyades 3 — there are only 5 minutes of arc between them and most people do not see these stars separately);
- Sigma 1 + Sigma 2 is a slightly dense and completely unnamed star couple.
If the first example (Theta) can somehow be called a double star, because both stars belong to the cluster and are somewhat gravitationally dependent (although the physical distance between them is large — 2 light years), then the second example (Sigma) is clearly optical. The weaker Sigma 1 does not belong to the Hyades, and lies 30 light-years behind the cluster.
A group of stars around double Theta looks beautiful — like a cluster within a cluster. Apparently, this is the central clot of the Hyades. It is very interesting to view it with strong binoculars or a telescope with low magnification.
Gamma Taurus — Hyad 1 — an orange giant, somewhat comparable to Aldebaran, which is much closer and therefore brighter, but if Aldebaran were among the Hyades, he would look about the same. Both of these stars have already left the main sequence of stellar evolution, and are currently burning out their helium reserves — ahead of them is the prospect of imploding into a white dwarf, with the previous drop of its outer shell, which will turn into a beautiful planetary nebula. But in the course of our lives, this will definitely not happen.
The group of stars Delta 1, Delta 2, Delta 3 raised questions at one time. The brightest of them — Delta 1 (or Hyad 2) — was considered not belonging to the cluster, and even now in the Stellarium program database, the distance to the star is 171 light years. But recent research has "returned" Hyad 2 to the Hyades. The error in determining the distance was due to the spectral binarity of the star. Now the distance is considered equal to 156 light years — quite typical for the Hyades.
Delta 2 is located on the far edge of the cluster, but still belongs to it. Officially considered a single star similar to Sirius in characteristics. But a noticeable X-ray flux from this star gives rise to the suspicion of the existence of an invisible companion nearby. Although, this is just a guess.
Delta 3, on the other hand, is a little closer to us than most stars in the cluster. This is a visual binary, and it can be separated into amateur telescopes at high magnification — the distance between the components is somewhat less than two arcseconds, and the second component is very faint — about 8m. It will take a lot of experience and patience to consider this star couple.
Some sources mention the proper name of Delta 3 Taurus — Cleea — apparently the only one of the stars in the cluster that retained the ancient name of one of the Hyades sisters.
The star already familiar to us — Epsilon Taurus — Ain — has a system of planets. The existence of at least one planet has been confirmed, and this is the first time planets have been found around a star in an open cluster. In 2015, this planet was officially given the name — "Amateru" — in honor of the Japanese goddess of the Sun. The planet is very large — 8 times more massive than Jupiter, and makes a revolution around its star in about two years.
A few degrees north of the authentic group of stars in the Hyades Cluster, several more can be found — Upsilon Taurus and the broad pair Kappa 1 and Kappa 2 Taurus. Ancient astronomers did not attribute them to the cluster, but now it is known that they also belong to the Hyades (as well as many of the fainter stars in this area of Taurus constellation, because in reality the Hyades are something more than what is visible to the eye).
Upsilon Taurus (the one to the north) is a delta Scuti type variable star, but the change in brightness of this star is very small — imperceptible to the eye.
Kappa 1 and Kappa 2 have been investigated for a possible strong gravitational bond that could allow the stars to stay together after the cluster completely breaks up. Indeed, the stars are located close enough to each other to be a binary system. But it turned out that the relative speed of these stars is too great for them to keep in touch in the future. These stars are flying away, although now there are only 16 thousand astronomical units between them, which is not much for stellar distances.
100 years ago, this pair of stars was used to experimentally confirm the Theory of Relativity, the consequence of which is the curvature of light rays when passing by a massive body. To do this, Kappa 1 and Kappa 2 were photographed near the Sun during a total eclipse.
All those stars that we see in the Hyades with our eyes are giant stars. Surely there are stars similar to the Sun in the cluster, but the Sun from such a distance would not be accessible to human vision, and would look like a faint luminary of the 9th magnitude. It's hard to see even with binoculars.
About a million years ago, the Hyades were twice as close to us and looked much brighter. But in that distant time, people were not up to the stars. Now the cluster is rapidly receding away — in the direction of Orion's belt. And in a million years, the Hyades will disappear from view — they will no longer be accessible to the naked eye of modern man. But who can know what physiological possibilities the people of the future will gain — perhaps they will become a hundred times more keen-eyed?
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