Lasers create table-top supernova
Laser beams 60,000 billion times more powerful than a laser pointer have been used to recreate scaled supernova explosions in the laboratory as a way of investigating one of the most energetic events in the Universe. Supernova explosions, triggered when the fuel within a star reignites or its core collapses, launch a detonation shock wave that sweeps through a few light years of space from the exploding star in just a few hundred years. But not all such explosions are alike and some, such as Cassiopeia A, show puzzling irregular shapes made of knots and twists. To investigate what may cause these peculiar shapes an international team led by Oxford University scientists (groups of Professor Gregori and Professor Bell in Atomic and Laser Physics, and Professor Schekochihin in Theoretical Physics) has devised a method of studying supernova explosions in the laboratory instead of observing them in space. 'It may sound surprising that a table-top laboratory experiment that fits inside an average room can be used to study astrophysical objects that are light years across,' said Professor Gianluca Gregori of Oxford University's Department of Physics, who led the study published . 'In reality, the laws of physics are the same everywhere, and physical processes can be scaled from one to the other in the same way that waves in a bucket are comparable to waves in the ocean. So our experiments can complement observations of events such as the Cassiopeia A supernova explosion.' The Cassiopeia A supernova explosion was first spotted about 300 years ago in the Cassiopeia constellation 11,000 light years away, its light has taken this long to reach us.


