Kirsten Banks is a guide at Sydney Observatory and is currently studying physics at UNSW. Below she discusses a recently observed supernova and explains what supernovae are.
Astronomers have recently discovered a monster supernova as bright as 570 billion Suns! This supernova, named the “Assassin”, lies approximately 3.8 billion light years from the Earth in a galaxy unknown to astronomers at this time. What makes this supernova so special, despite its massive brightness, is its energy output. It is the most powerful supernova ever discovered in human history.
But what is a supernova?
A supernova, in its simplest form, is the result of a star reaching the end of its lifetime. As a star dies, i.e. runs out of fuel or stuff to burn, it cannot stabilise against its own gravity so it collapses in on itself and then explodes in often a very pretty way, resulting in a very bright blast that can sometimes be seen in daylight! For example, a supernova remnant a little closer to home is the Crab Nebula. This nebula lies about 6,000 light years away from the Earth and can be seen in the constellation of Taurus at this time of year. The supernova which formed the Crab Nebula, when it originally exploded in 1054 AD, outshone all the other stars in the sky for up to two years – it was even visible in broad daylight for a number of weeks! You can find the remnant of this supernova in the constellation of Taurus with a reasonably good telescope, even those with binoculars can see the fuzzy gas of the nebula located just below the top horn (zeta Tau) star of Taurus, as viewed from the southern hemisphere.