Even non-astronomy people can easily find the constellation of Ursa Major. Or at least his most memorable part – the bucket. Seven Stars Bucket – Dubhe, Merak, Fegda, Megrez, Alioth, Mizar and Benetnash – all about the same color and similar light, dominated by bright luminaries in the impoverished northern part of the sky and stand out in the constellation familiar from childhood. Dubhe a star tied the Big Dipper turns out to be a uniqueWhite Dwarf
Large accumulationSuch neighborhood of bright stars in the sky is not random: most of the stars visible to the eye of the Great Bear (with the possible exception Dubhe and Benetnasha) is a diffuse star cluster. they were formed together about half a billion years ago and gradually spread out from each other. The cluster is in principle no different from the most notable representative of this class of objects – clusters of M45 (the Pleiades, or Stozhary), seven of the brightest stars, which even lined up in similar shape bucket.
The main difference between the Big Dipper from other clusters in that it is very close to the Sun, about 80 light years away from our star. Therefore, a ladle and takes in the sky such a large area, allowing him to name the constellation. For the same reason, the relative motions of the stars of the Dipper are clearly visible even on the scale of human life. When the ancients were the first star maps, the Big Dipper was different from its present shape so that it can be seen with the naked eye. And when people first looked up into the sky, the Big Dipper looks completely wrong, as it is now – 50 thousand years ago, this constellation does not like to scoop, but rather on the ladle.
On horsebackOne of the stars of the Big Dipper – Mizar, located on a break bucket handle – there is a well-known neighbor – Alcor. This star is about 5 times weaker at a distance of about 11 arc minutes from Mizar. Together they are sometimes called “horses” (Mizar) and “Rider” (Alcor). Notice partner is not that difficult, but in many cultures, the ability to see the Horseman was considered a sign of good vision.
According to the legend, responsible for the wide dissemination of which lies on the American lexicographer second half of the XIX century, Richard Allen, the ability to see Alcor ancient Arabs and the Romans felt the future of archers. In Japan, Alcor, in contrast, has earned the dubious glory of the stars – the precursor of death: if the vision is weakened to an inability to distinguish against the background of Alcor Mizar, its owner was considered an old man, living out its last years.
Wide vague11 minutes of arc in the sky at a distance of 80 light years – is at least three trillion miles, 18,000 astronomical units or something around 0.3 light years. This is a fairly wide double, and the question related to whether the Mizar and Alcor are physically or just happened to be in the sky nearby, is still not resolved.
In the literature one can find a variety of statements from the iron certainty the presence of the gravitational links between them to no less stringent belief that Alcor and Mizar – a classic example of the so-called optical double – a pair of stars, accidentally caught up in the sky next to each other.
Previously, some astronomers have even speculated that Alcor is alien not only Mizar, but the entire cluster of the Big Dipper as a whole, but recent work confidently placed rider in the number of members of the cluster. However, what about the physical link is no certainty – and the distance between them is large, and their velocity vectors are slightly different, as if the star is gradually diverge.
Multiple starMeanwhile, to understand this connection we would like. The fact that the wide binary systems are very sensitive to initial conditions of star formation and further evolution of the cluster, and their very presence can limit the average density of stars and gas: the double-wide fall of very small perturbations.
In addition, the pair Mizar, Alcor – is not just double, but at least five-time system. Already in the observations with a small telescope Mizar decomposes into a pair of bright stars, and the spectra of each of them show a periodic shift of the lines, proving that each component of this pair – a double star itself. So Mizar – hierarchical quadruple system, a pair of close pairs.
Yes, and Alcor suspect in the duality of the jump lines in its spectrum, found more than half a century ago. However, the jumps are so irregular that they can not be caused by the presence of the second component, and repeated observations on modern instruments also do not confirm the results of half a century ago. And yet, the approval of the duality of Alcor, and hence the sixth of Mizar, Alcor, continue to roam from one popular article to another.
Carlitz EleanorOddly, Mizar and Alcor – it seems really sixfold system. In the article , which will soon be launched in the Astronomical Journal, researchers led by Eric Mamadzheka the University of Rochester announce the opening of the star Alcor B. Each other astronomers call her Eleanor.
Companion Alcor is not found in the spectrum of this star, but directly on the photo light received in the infrared with adaptive optics systems using 6.5-meter MMT telescope in the U.S. state of Arizona. On the palate Eleanor is just one arcsecond from Alcor A, but it is 100 times weaker than him, so that it could see, only filtering out atmospherics and shaded in the picture brighter companion.
If such proximity – not an accident (and the probability of coincidence – just over 1 million), the Eleanor – a small star that is spinning about 25 astronomical units (4 billion miles) from Alcor A. It’s either the cooling white dwarf mass of about 0,6-0,7 mass of the Sun, or, more likely, the dim red star, which is about three times lighter than our star.
Attraction in the family
Attraction Eleanor unable to Alcor A velocity jump, which is half a century ago to observe its spectrum, or not. However, it angers him move around in that direction and at such a rate at which a motion vector different from Alcor Mizar motion vector. Hence, the pair Alcor A
Even non-astronomy people can easily find the constellation of Ursa Major. Or at least his most memorable part – the bucket. Seven Stars Bucket – Dubhe, Merak, Fegda, Megrez, Alioth, Mizar and Benetnash – all about the same color and similar light, dominated by bright luminaries in the impoverished northern part of the sky and stand out in the constellation familiar from childhood. Dubhe a star tied the Big Dipper turns out to be a uniqueWhite Dwarf
Large accumulationSuch neighborhood of bright stars in the sky is not random: most of the stars visible to the eye of the Great Bear (with the possible exception Dubhe and Benetnasha) is a diffuse star cluster. they were formed together about half a billion years ago and gradually spread out from each other. The cluster is in principle no different from the most notable representative of this class of objects – clusters of M45 (the Pleiades, or Stozhary), seven of the brightest stars, which even lined up in similar shape bucket.
The main difference between the Big Dipper from other clusters in that it is very close to the Sun, about 80 light years away from our star. Therefore, a ladle and takes in the sky such a large area, allowing him to name the constellation. For the same reason, the relative motions of the stars of the Dipper are clearly visible even on the scale of human life. When the ancients were the first star maps, the Big Dipper was different from its present shape so that it can be seen with the naked eye. And when people first looked up into the sky, the Big Dipper looks completely wrong, as it is now – 50 thousand years ago, this constellation does not like to scoop, but rather on the ladle.
On horsebackOne of the stars of the Big Dipper – Mizar, located on a break bucket handle – there is a well-known neighbor – Alcor. This star is about 5 times weaker at a distance of about 11 arc minutes from Mizar. Together they are sometimes called “horses” (Mizar) and “Rider” (Alcor). Notice partner is not that difficult, but in many cultures, the ability to see the Horseman was considered a sign of good vision.
According to the legend, responsible for the wide dissemination of which lies on the American lexicographer second half of the XIX century, Richard Allen, the ability to see Alcor ancient Arabs and the Romans felt the future of archers. In Japan, Alcor, in contrast, has earned the dubious glory of the stars – the precursor of death: if the vision is weakened to an inability to distinguish against the background of Alcor Mizar, its owner was considered an old man, living out its last years.
Wide vague11 minutes of arc in the sky at a distance of 80 light years – is at least three trillion miles, 18,000 astronomical units or something around 0.3 light years. This is a fairly wide double, and the question related to whether the Mizar and Alcor are physically or just happened to be in the sky nearby, is still not resolved.
In the literature one can find a variety of statements from the iron certainty the presence of the gravitational links between them to no less stringent belief that Alcor and Mizar – a classic example of the so-called optical double – a pair of stars, accidentally caught up in the sky next to each other.
Previously, some astronomers have even speculated that Alcor is alien not only Mizar, but the entire cluster of the Big Dipper as a whole, but recent work confidently placed rider in the number of members of the cluster. However, what about the physical link is no certainty – and the distance between them is large, and their velocity vectors are slightly different, as if the star is gradually diverge.
Multiple starMeanwhile, to understand this connection we would like. The fact that the wide binary systems are very sensitive to initial conditions of star formation and further evolution of the cluster, and their very presence can limit the average density of stars and gas: the double-wide fall of very small perturbations.
In addition, the pair Mizar, Alcor – is not just double, but at least five-time system. Already in the observations with a small telescope Mizar decomposes into a pair of bright stars, and the spectra of each of them show a periodic shift of the lines, proving that each component of this pair – a double star itself. So Mizar – hierarchical quadruple system, a pair of close pairs.
Yes, and Alcor suspect in the duality of the jump lines in its spectrum, found more than half a century ago. However, the jumps are so irregular that they can not be caused by the presence of the second component, and repeated observations on modern instruments also do not confirm the results of half a century ago. And yet, the approval of the duality of Alcor, and hence the sixth of Mizar, Alcor, continue to roam from one popular article to another.
Carlitz EleanorOddly, Mizar and Alcor – it seems really sixfold system. In the article , which will soon be launched in the Astronomical Journal, researchers led by Eric Mamadzheka the University of Rochester announce the opening of the star Alcor B. Each other astronomers call her Eleanor.
Companion Alcor is not found in the spectrum of this star, but directly on the photo light received in the infrared with adaptive optics systems using 6.5-meter MMT telescope in the U.S. state of Arizona. On the palate Eleanor is just one arcsecond from Alcor A, but it is 100 times weaker than him, so that it could see, only filtering out atmospherics and shaded in the picture brighter companion.
If such proximity – not an accident (and the probability of coincidence – just over 1 million), the Eleanor – a small star that is spinning about 25 astronomical units (4 billion miles) from Alcor A. It’s either the cooling white dwarf mass of about 0,6-0,7 mass of the Sun, or, more likely, the dim red star, which is about three times lighter than our star.
Attraction in the family
Attraction Eleanor unable to Alcor A velocity jump, which is half a century ago to observe its spectrum, or not. However, it angers him move around in that direction and at such a rate at which a motion vector different from Alcor Mizar motion vector. Hence, the pair Alcor A
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