378
Scientists have discovered cold stars - Y-dwarfs
A year ago, researchers NASA announced that found 14 stars with the cold surface temperature of all known subzvёzdnyh objects - the so-called brown (or brown) dwarfs. Recently, however, were found even more "cold" stars - «Y-dwarfs' surface temperature is below human body temperature (the letter Y has been specifically introduced in Harvard classification to describe this new type stars). The temperature of the coldest of them is only 26, 6 degrees Celsius.
Astronomers often called brown dwarfs-and Y-dwarf "stars-losers", as these cosmic bodies have too low density, because of what can not be heated to a temperature characteristic of other stars. For comparison: the average density of the Sun is 1409 kg / m³, the temperature of the surface - about 6000 K, and the core temperature - about 13, 5 million K. The sun will shine we still have at least a few billion years, in contrast to the "cold" stars. Heat is carried out in the past by the nuclear reaction of hydrogen with reserves in the nuclei of these stars are small, as a result they quickly cool down and, in the end, "go out", turning into a kind of planets.
In addition, the "cold" stars emit light in the infrared range, invisible to the human eye, which is why they are very difficult to detect: NASA is possible thanks to the infrared telescope. But the most surprising is not it - affects how close the Y-dwarfs are away: only some 10.5 light years.
via factroom.ru
Find out the reason that pencils are always yellow
Above the river in Venezuela Catatumbo lightning shine 160 days a year (and not accompanied by thunder)