Astronomers have detected what they say is the biggest explosion in the universe – the largest since the Big Bang. Researchers say the blast took place 390 million light-years away in a supermassive black hole, leaving a ‘crater’ the size of 15 Milky Ways. So how big was this explosion?  Scientist Melanie Johnston-Hollitt compared it to a 20 billion-billion megaton TNT explosion going off every thousandth of a second – for 240 million years.  In other words, “Huge”. What do you think caused this massive explosion?  Do you think astronomers will ever discover alien life?