The most known among all existing stars – the Sun. It cannot brag of the sizes or high temperature, but it is the center of our Solar system and a source of life on Earth. Most of people also know about such stars as Sirius, Polar, Proxima of the Centaur.
Sun
In the ancient time people did not understand what nature the Sun has, and today most of school students know that it is a star, and not the largest and bright, and simply located very close to Earth in comparison with other stars. For the rest it has no essential differences from them: it is a huge and heavy sphere from gas in which there are thermonuclear reactions. As a result it heats up to huge temperatures and has the strong radiation to which life on Earth is obliged. The sun consists of hydrogen, helium and several other elements, at it in rather small amounts there are a calcium, iron, neon, silicon, nitrogen.
The sun together with the planetary system is on the edge of our Galaxy, doing a turn around its center for 200 million years. It is a relatively young star – its age about 4.5 billion years. As much again time has to pass that it turned into red giant.
Sirius
Sirius – one of the most known stars in a firmament thanks to what has the largest brightness (after the Sun). This is not the champion on brightness, he only by 22 times shines stronger, than the Sun (there are much more powerful stars), but as it is located rather close, is the most noticeable in the night sky. Sirius is visible almost from any point of Earth, except the most northern regions. Actually Sirius is a double star: senior of couple is a white dwarf and by the sizes concedes to the Sun, and younger, Sirius And, it is just visible from Earth. Age of this space object – about 230 million years.
Pole star
The pole star is known that with its help it is possible to be guided by areas. It always is over the northern horizon, it it is visible only in the Northern hemisphere. There is it in the constellation of Little Dipper, on the end of "ladle". A pole star – the brightest among the pulsing variable stars. It represents a supergiant and has two partners much of the smaller size. There is it in 323 light years from Earth. Its official name – the Alpha of Little Dipper.
Proxima of the Centaur
The Proxima of the Centaur is not so well-known as the Pole star or Sirius, but too it is possible to call it known as it is most closer to Earth after the Sun. The Proxima small by the sizes, is the red dwarf. It is located in only 4.2 light years from our planet. Despite such proximity, it cannot be seen with the naked eye because of dim light.