Friday, November 2, 2012
What occur to the very first stars in the universe?
Most distant and bright supernova, known to scientists today, probably happens in the explosions when the universe was much younger - just after the Big Bang.
What both these unusually bright and slowly fading. These properties are consistent with what is known as a supernova with the pair instability, a rare explosion mechanism, which is expected to occur with massive stars, is substantially free of metals.
That these were the very first stars, "said Raymond Carlberg with the Department of Astronomy and Astrophysics, University of Toronto.
Two supernovae identified as SN2213 and SN1000 +2016, were discovered during the Canada-France-Hawaii Telescope Legacy Survey. In recent years, various surveys have allowed astronomers to open new windows in the universe, including the discovery of fluorescent supernovae that are 10-100 times brighter than ordinary supernovae. "Canada-France-Hawaii Telescope Legacy Survey - the first is the deepest view of the sky, which showed a massive area of the universe," said Carlberg.
Data processing was carried out at the University of Toronto with search technology, which first narrows search zvezdoformiruyuschih of galaxies with large redshifts, and then looks for supernovae, which are brighter than ordinary stars such unusually long and go out - the exact characteristics of a pair instability supernova.
Explosion mechanism with the pair instability observed in stars, which are about 150-300 times the mass of the sun, said Carlberg. In today's universe are so massive forms, because when such stars begin to burn, then pushing a lot of gas. In the early days of the universe metal abundance in the gas was almost zero, which means it was almost transparent, and could fall to form stars.
Such stars are short-lived. They are so hot in the middle of that pressure is lost, and eventually formed a collapse, which heats the core even more. Created as a result of oxygen and silicon, which causes the fusion of a nuclear explosion, much brighter than the other mechanisms of the supernova.
The Beijing University of Aviation and Cosmonautics completed a 370-day experiment to simulate the lives of people on the moon, settin...
United Launch Alliance Company successfully conducted the launch of a rocket Delta IV , which brought with it the WGS-9 satellite for mi...
The following month, the NASA spacecraft "Cassini" will make his 126th and final passage by Saturn's largest moon Titan . ...
The spacecraft SpaceX Dragon US company made a successful soft landing on Earth, splashed down off the coast of southern California nea...