The Universe�s BIGGEST explosion�second only to the Big Bang�captured in unprecedented
detail
Astronomers have captured the biggest explosion in the universe�so bright, that it may have
been visible with a pair of binoculars, and only second largest to the big bang�in unprecedented
detail.
This artist�s impression shows two galaxies in the early Universe.
The brilliant explosion on the left is a gamma-ray burst.
The light from the burst travels through both galaxies on its way to Earth (outside the
frame to the right).
Caused by the explosive wrath of a massive star, one of the most powerful explosions
in the known universe has been recorded by scientists.
But not only that, scientists also but the breakthrough has offered astronomers insight
into gamma ray bursts, a cosmic phenomenon which has baffled astronomers ever since they
were first detected in the 1960�s.
The explosion was so powerful that it gave off as much energy in a few seconds than our
sun in its 10 billion years life.
The cosmic explosion was so massive that it would easily have been visible with only a
pair of binoculars�even though it occurred a staggering 10 billion light years away�according
to astrophysicists.
Gamma rays occur when a massive star dies, collapsing into a black hole, exploding as
a supernova.
It spews jets of gas across the cosmos at the speed of light which is highly dangerous
for any planet along their way.
Curiously, a mass extinction on Earth around 450 million years ago is believed to have
been caused by a massive gamma ray burst in a nearby part of our galaxy.
In fact, this explosion is the second largest to the Big Bang.
Capturing it was a moment of unimaginable luck admit experts, as the team recorded the
short-lived even which last usually from a few milliseconds to up to a minute.
In fact, by only a one-in-10,000 chance experts at Bath University, together with their colleagues
at NASA, managed to detect its light as the star died.
Head of physics Professor Carole Mundell commented the event saying:
�It was so bright you could have observed it with a pair of binoculars.
�They usually occur instantly, however this time we got a flash of light lasting a second
that served as a warning.
Then there was a delay of about 100 seconds, which gave us enough time to position the
telescopes.
�That is quite unusual, and the burst lasted longer than normal, a few minutes which was
fortunate.
�Although very distant, this burst was extremely powerful and bright and we were excited when
we realized our super-fast robotic telescopes had captured the early time light.�
Short-lived Gamma Ray Bursts are extremely bright flashes of light spotted by space-based
telescopes orbiting our planet.
However, scientists have struggled to explain them with standard explosion theories.
Scientists suspected how magnetic fields had something to do but that was extremely difficult
to prove as the explosion happen millions of light-years away from Earth and disappear
in a matter of seconds or minutes.
However, by using state-of-the-art autonomous robotic telescopes, astronomers were able
to measure a special property of the light probing the magnetic fields�its polarization.
Astronomers believe that strong magnetic fields form in close proximity to the new black hole
and drive energy and cosmic material outwards in a powerful, tightly focused beam.
The new study has allowed experts also to learn more about synchrotron radiation�a
phenomenon that occurs when electrons accelerate in a curved pathway�which power the initial
highly powerful phase of the burst, referred to as the �prompt� phase.
�We have demonstrated previously, with the help of slower autonomous robotic telescopes
that magnetic fields must be significant and help guide the material outwards at great
speeds.�
�But, until now, we were never fast enough to capture bright visible light at the same
time as the high energy gamma rays generated during the explosion itself.
There is serious debate about the origin of these high speed flows � how material can
be accelerated to such extremely high speeds, what physical mechanism produces the light
that we observe with our high-energy satellites, and most importantly, what, if anything, is
the role and origin of the magnetic fields,� concluded Professor Mundell.
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