The first is the Spring Triangle. The constellation of Virgo contains many interesting objects. It even contains 11 Messier objects. Another interesting association is with the Behenian fixed stars. In medieval astrology, Spica was part of the fifteen Behenian stars who were believed to have an influence on the planets and a source of astrological power or even magic. The primary Spica star is halfway between a subgiant and a giant on the evolutionary stage. Because of this, and its enormous mass, it is believed that the star is massive enough to end its life in a supernova explosion of Type II.
The primary star is a blue giant and a variable star of the Beta Cephei type. Spica, along with Arcturus and Regulus, are part of the Spring Triangle asterism, and by extension, also of the Great Diamond together with the star Cor Caroli. Since Spica is 2. Spica is around The stars orbit each other once every four days and they are so close to one another that they cannot be resolved as two stars through a telescope.
Formation Spica is estimated to have formed around Location Spica is located in the zodiacal constellation of Virgo. The Future The primary Spica star is halfway between a subgiant and a giant on the evolutionary stage.
Did you know? The best time to observe the stars and deep-sky objects situated in the Virgo constellation is during the month of May. The best time to observe Spica, in particular, is from spring to late summer.
It emerges on the horizon in the east-southeast at sunset in mid-April. It depends on the mass of the star. The lower the mass, the longer it will stay on the main sequence.
A red dwarf may stay on the main sequence for trillions of years, while a blue star only lasts a few million years. An O star will stay on the main sequence for millions of years whereas a M star can stay on the main sequence for billions and billions of years.
The Sun will stay on the main sequence [Fusing hydrogen] for about another 5 billion years. About another 4. As gravity pulls a star together in the main sequence the increased density and heat causes faster nuclear fusion of hydrogen into helium. This force tries to expand the star. But the more the star expands the slower and less powerful the fusion. These two forces come into equilibrium until the hydrogen runs low. This takes a relatively long time. In other stages of stars life cycles they are not in equilibrium.
Either the force of gravity or the expanding forces are stronger. In these cases the star contracts or expands. There are other stable states for stars besides the main sequence. These sometimes do not last as long as the main sequence because the force keeping the star from collapsing further does not last as long. Some star states are actually more stable than the main sequance stage though. White dwarf stars will stay white dwarfs for longer than main sequence stars will stay in the main sequence.
The length of time that a star stays in the main sequence varies by a huge amount depending on its mass. The whole reason is much too long and complicated to be placed here.
You need to read an encyclopedia article on the different classes of the starts. However, the simple summary is that the largest and hottest stars stay in the main sequence for the shorter lengths of time like 10 million years , but the smaller and cooler stars smaller than our Sun stay in the main sequence for the longest lengths of time - billions and billions of years, really long, like 50 billion years.
Our Sun is in between, and it has an estimated lifetime of about five billion years on the main sequence. That varies a lot, depending mainly on the star's mass. The largest stars are very short-lived; they might stay on the main sequence for just a few million years. Stars the size of our Sun, somewhere in the middle note, however, that our Sun is already in the top 10 percentile! The "main sequence" basically consists of all those stars that fuse hydrogen-1, converting it into helium A massive star will remain in the main sequence while it has enough hydrogen-1; but since it gets hotter and burns its fuel much faster, it may stay there only for a fairly short time - in the case of the most massive stars, just a few million years.
It will stay on the main sequence until all of the hydrogen in the core has been used up. See related question. Around 10 billion years. The least massive stars stay on the main sequence the longest since they don't go through their fuel their hydrogen as quickly as bigger stars do. This is because bigger stars have to fight against more gravity, so they have to fuse their hydrogen at a faster rate than smaller stars. Once a star stops fusing hydrogen into helium at its core and starts fusing heavier elements or just stops fusion altogether , it leaves the main sequence.
About 10 billion years. That's the time estimated for our Sun - it has already existed for some 5 billion years, and will continue shining for another 5 billion years. The energy source is hydrogen undergoing nuclear fusion to helium.
The time that lasts depends on the mass of the star but it usually takes a few billion years. Objects above this mass fuse hydrogen too rapidly and cannot stay together. But if the body has sufficient mass, the collapsing gas and dust burns hotter, eventually reaching temperatures sufficient to fuse hydrogen into helium. The star turns on and becomes a main sequence star, powered by hydrogen fusion. Fusion produces an outward pressure that balances with the inward pressure caused by gravity, stabilizing the star.
How long a main sequence star lives depends on how massive it is. A higher-mass star may have more material, but it burns through it faster due to higher core temperatures caused by greater gravitational forces. While the sun will spend about 10 billion years on the main sequence, a star 10 times as massive will stick around for only 20 million years. A red dwarf , which is half as massive as the sun, can last 80 to billion years, which is far longer than the universe's age of This long lifetime is one reason red dwarfs are considered to be good sources for planets hosting life , because they are stable for such a long time.
More than 2, years ago, the Greek astronomer Hipparchus was the first to make a catalog of stars according to their brightness , according to Dave Rothstein, who participated in Cornell University's "Ask An Astronomer" website in In the early 20th century, astronomers realized that the mass of a star is related to its luminosity , or how much light it produces.
These are both related to the stellar temperature. Stars 10 times as massive as the sun shine more than a thousand times as much. The mass and luminosity of a star also relate to its color. More massive stars are hotter and bluer, while less massive stars are cooler and have a reddish appearance.
The sun falls in between the spectrum, given it a more yellowish appearance. This understanding lead to the creation of a plot known as the Hertzsprung-Russell H-R diagram, a graph of stars based on their brightness and color which in turn shows their temperature.
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