Images of supernovae minutes after ignition challenges main theory of formation

An international group of researchers has caught the earliest images of supernovae in action - only minutes after detonation - and they say these gigantic planetary blasts are happening after stars strike, puzzling theories that supernova take place in a uniform way. A supernova is a planetary explosion that can momentarily surpass the whole galaxy, comprised of billions of stars. Using the Kepler space telescope, investigators snapped three of these cosmic events between 600 and 1.8 billion light-years from Earth. They were observing especially at type IA supernovae, which include the explosive deaths of elderly white dwarf stars that occur in a binary orbit with a companion star. Astrophysicist and group fellow Brad Tucker, from the Australian National University, told Stuart Gary at ABC Science "We were able to capture the supernovae in the first minutes of the bang, the earliest before had been two-and-a-half hours after the event," The group followed the blasts in detail until they reached their peak of illumination three weeks later, and then checked the succeeding declines, as their light signs faded away over the next few months.
Image Credit: Brad Tucker and Emma Kirby

They found that the early stages of their supernovae didn't fit very well with dominant theories about how they arise. Before their study open an extraordinary indication into the early stages of these astronomical phenomena, astronomers only had data about what was happening in type IA supernovae 2.5 hours after the star's explosive vanishing process had started. What they detected was that after this 2.5-hour spot, the fading stars all showed a matching pattern. This directed to theories that they might also start in similar ways.  The leading theory has been that these blasts happen when the solid white dwarf - or the vanishing star - uses its gravity to pull burning material from its companion star onto its exterior. Eventually, the added heat and pressure causes the star's core to blast. But the group found no indication of the supernovae ejecta interrelating with a companion star, as might be predictable.

The group's study, which were freshly published in Nature, deliver new vision into how some of these explosions form and could help astronomers use their light signatures to more accurately measure intergalactic distances between galaxies.

But it doesn't cancel out the other development theory: a second paper printed in the same topic of Nature by a different group has found evidence to support the view that these events can still be produced by stars accreting matter from their companion.

The crew from the California Institute of Technology used NASA's Swift space telescope to study a supernova 300-million-light-years away. They found that as the expelled material extended outwards it finally stricken with the companion star. They say this delivers proof that the explosion is resulting from a single disintegrating star, rather than a collision.
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Images of supernovae minutes after ignition challenges main theory of formation Images of supernovae minutes after ignition challenges main theory of formation Reviewed by Umer Abrar on 5/30/2015 Rating: 5

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