Astronomers on Wednesday (May 21, 2008) said they witnessed for the first time how a dying star erupted into a supernova, one of the mightiest yet most elusive sights in the Universe.
Supernovae are massive stars that run out of fuel, collapse under the weight of their own gravity and become an ultra-dense object known as a neutron star.
They then send out a shockwave that rips the star apart and leaves a sizzling cauldron of radiation.
These colossal events are among the most thrilling phenomena for astronomers but are also agonizingly hard to detect. They are usually only spotted days or weeks after they occur, becoming visible when material from the blast collides with gas and dust that the star had shed earlier. This high-energy smash creates a dramatic flare which eventually fades.
In January, though, a “once-in-a-lifetime” stroke of luck enabled astronomers to spot a supernova in its infancy, skygazers reported in the British journal, Nature.
Princeton University’s Alicia Soderberg had asked NASA mission controllers to orientate their orbital X-ray telescope, Swift, to observe the glowing remnants of a two-week-old supernova in a spiral galaxy called NGC 2770, 90 million light years from Earth.
But, by sheer good fortune, another supernova was brewing nearby, sending out a burst of X-rays that Swift instantly picked up and started to record. “It is a really lucky chain of events. It was all over in a matter of minutes,” said Ms.Soderberg.
The satellite’s precious 530 seconds of data confirm a theory postulated nearly four decades ago that supernova would be heralded by an X-ray burst. – AFP
Courtesy: The Hindu, Madurai, May 22, 2008 (Grandstand View of Supernova).
Grateful thanks to AFP and The Hindu.
Supernovae are massive stars that run out of fuel, collapse under the weight of their own gravity and become an ultra-dense object known as a neutron star.
They then send out a shockwave that rips the star apart and leaves a sizzling cauldron of radiation.
These colossal events are among the most thrilling phenomena for astronomers but are also agonizingly hard to detect. They are usually only spotted days or weeks after they occur, becoming visible when material from the blast collides with gas and dust that the star had shed earlier. This high-energy smash creates a dramatic flare which eventually fades.
In January, though, a “once-in-a-lifetime” stroke of luck enabled astronomers to spot a supernova in its infancy, skygazers reported in the British journal, Nature.
Princeton University’s Alicia Soderberg had asked NASA mission controllers to orientate their orbital X-ray telescope, Swift, to observe the glowing remnants of a two-week-old supernova in a spiral galaxy called NGC 2770, 90 million light years from Earth.
But, by sheer good fortune, another supernova was brewing nearby, sending out a burst of X-rays that Swift instantly picked up and started to record. “It is a really lucky chain of events. It was all over in a matter of minutes,” said Ms.Soderberg.
The satellite’s precious 530 seconds of data confirm a theory postulated nearly four decades ago that supernova would be heralded by an X-ray burst. – AFP
Courtesy: The Hindu, Madurai, May 22, 2008 (Grandstand View of Supernova).
Grateful thanks to AFP and The Hindu.
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