A snapshot of a Type Ia supernova simulation taken very shortly after the moment of detonation. The energy released during the detonation is equivalent to 1,027 hydrogen bombs, each equivalent to 100 megatons of TNT.
Credit: DOE NNSA ASC/Alliance Flash Center
SYDNEY: Simulating spectacular supernovae could help unlock some of the darkest secrets of the cosmos, say scientists. They are using the world's fastest supercomputer – the Argonne Blue Gene/P – to model exploding stars.
During these video simulations a seemingly innocuous yellow dot appears in the centre of the star. The dot stretches and mushrooms into a gigantic ball of nuclear energy, pushing through to the surface of the star, blistering out and eventually enveloping the star in an immense nuclear deflagration. Watch a video of one of the simulations here.
In reality the process would take less than five seconds and yield an unimaginable quantity of energy. The energy released during the detonation alone is equivalent to 1,027 hydrogen bombs.
Dark energy data
While the spectacle itself is impressive, mimicking exploding stars could also help scientists answer one of the biggest questions in modern physics: why the universe is expanding.
Because all supernovae explode with more-or-less the same brightness, scientists can use them to measure distances in space.
"Being able to measure distances in the universe accurately is critical for understanding dark energy, the theorised cause of the unexpected discovery that our universe is expanding," explained Cal Jordan of the University of Chicago's Centre for Astrophysical Thermonuclear Flashes. Accurate simulations of supernovae will allow his team to fine-tune these distance measurements, he said.
The whole process of simulating a supernova takes three days using the Argonne Blue Gene/P (BGP) supercomputer, but would take around 1,000 years using an ordinary desktop computer.
160,000 processors
"The Argonne Blue Gene/P supercomputer is one of the largest and fastest supercomputers in the world," said co-worker Robert Fisher. "It has massive computational resources that are not available on smaller platforms elsewhere." The BGP has over 160,000 processors pitching in on the same problem, he added.
But why go to the trouble of simulating the process, when supernovae are happening all over the sky, and can be observed form a telescope? Jordan explains: "When we look up into space we can only observe the results of the explosion, and have never caught a supernova in the act of exploding."
The simulation will help scientists better understand how supernovae work, and test their new theories about this awe-inspiring process.
