A team of astronomers believe they have found a new class ofstellar explosionswhen reviewing the data of asupernova discovered seven years ago. Until now it was thought that supernovae came from explosions of white dwarfs or massive stars that collapse, but this third type seems to developquickly from a binary star system, in which thehelio it circulates from one white dwarf to another producing thermonuclear explosions.
At work, posted inScience and led by the astronomer Dovi Poznanski of the University of California at Berkeley and the Lawrence Berkeley National Laboratory (USA), the new star is described, baptized with the name ofSN 2002bj. “It is the fastest evolving supernova we’ve ever seen,” Poznanski notes, explaining: “Its speed was three to four times that of a standard supernova and it basically disappeared in a matter of 20 days. Its brightness just faded by a seen and not seen “.
“It is the fastest evolving supernova we have ever seen,” Poznanski points out. “Its speed was three or four times that of a standard supernova and it hasbasically gone in a matter of 20 days. Its brightness simply faded in a seen and unseen “.” We think it could be a new physical explosion mechanism ?, adds his partner Alex Filippenko.
The supernova was detected in 2002 in thegalaxia NGC 1821, in the constellation Lepus, by the automatic imaging telescopeKatzman (KAIT). Due to an unfortunate crossover of circumstances, the astronomical community mistakenly classified it as a common type II supernova and outright shelved it. In June, Poznanski came across the spectrum by chance when looking for type II supernovae as distance indicators to confirm the expansion rate of the universe. By carefully studying a high-quality spectrum of SN 2002bj, he realized that it was not a type II supernova.
Scientists now propose the existence of binary systems composed of two white dwarfs, one of which is made up mainly of helium, and which is slowly pulled by gravity towards its companion.
Poznanski also hopes that the current poll Palomar Transient Factory, which uses a wide-field camera to track new objects in the sky every day, helps to find more supernovae such asSN 2002bj.
