Researchers Map Out Evolution of Hibernating Star Explosion
For the first time, astronomers were able to observe the transition of a white dwarf star with low and unstable mass-transfer rate leading to the so-called classical nova, or the final explosion of a white dwarf.
Unlike supernova explosion, classical nova is relatively weak and do not destroy their parent star nor signify the death of the star. As a white dwarf and another active star orbit one another in a binary system, the white dwarf sucks matter away from its companion star. As matter is being pulled away from the active star, hydrogen begins to accumulate on the surface of the white dwarf, starting fusion, which leads to the explosion.
Their observations, described in a paper published in the journal Nature, provided the first direct evidence for what the scientists called nova hibernation hypothesis, a theory suggesting that the mass-transfer rate between a white dwarf and its companion star increases after classical nova and dramatically decreases over a million years, in which the star goes to hibernation.
"The entire system survives the nova explosion... so the whole process starts again," said Przemek Mróz, a PhD student at the Warsaw University Astronomical Observatory and first author of the paper, in a report from BBC. "After thousands of years, our nova will awake and explode again but no one will be able to see it."
According to the report from CNN, the findings of astronomers were all by chance. In 2005, the Very Large Telescope was aimed at a potential exoplanet tha happens to be in the same area as the V1213 Cen, or Nova Centauri 2009, a binary star system in the Centaurus constellation. Images of the V1213 Cen and its companion star were taken during that time.
Four years later, the Polish astronomical project Optical Gravitational Lensing Experiment (OGLE), which was originally built to detect dark matter, captured the area of V1213 Cen, before, during and after its explosion in 2009.