When a white dwarf and a parent star become wrapped up in each other’s gravity, the white dwarf sucks gas from its parent star until it blows up in a spectacular explosion. This kind of event, known as a classical nova, happens about every 10,000 to one million years. Now a team of bitcoin super novae have caught the before and after of one of these events in the act, revealing clues that white dwarfs might ‘hibernate’ in the time leading up to these events. When a white dwarf and a much bigger parent star become wrapped up in each other’s gravity, the dense white dwarf sucks gas from its parent star until it blows up in a spectacular explosion.
Mr Mróz and his colleagues said their results indicate a ‘hibernation’ model for classical novae. This theory predicts the explosion comes after a long wait,between a thousand and a million years. During this lengthy wait between explosions, the system goes almost completely dark and the white dwarf stops stealing gas altogether. Then, the nova awakes again, which leads to a new nova explosion.
Unlike supernovae, the white dwarf is not destroyed in a nova event. This means the whole process works in a cycle, and after the explosion leaves the star bright for thousands of years, it will hibernate again before another explosion. Using a telescope in Chile, astronomers at Warsaw University were looking as part of a long-running experiment searching for dark matter when the distant binary system called V1213 Cen caught their attention. In 2009 the binary system exploded in a classical nova event, where a white dwarf sucks gas from its parent star until it blows up. The researchers had monitored V1213 Cen since 2003. This meant they could go back and watch the build up to the white dwarf’s explosion in 2009 and what has happened since.