Telescopes at the Mauna Kea and Haleakala observatories have measured
the distance to the most distant cosmic explosion ever seen, opening a
new view into the frontiers of space.
The explosion, known to astronomers as a "gamma-ray burst", was first
detected by NASA's Swift satellite on Sunday morning before being
pinpointed by telescopes in Chile. Telescopes around the world rushed
to catch a glimpse of the fading explosion, including the Subaru
telescope and NASA's Infrared Telescope Facility (IRTF) on Mauna Kea,
and the MAGNUM telescope on Haleakala.
Nobuyaki Kawai from the Tokyo Institute of Technology led a team that
used the 8.2 meter Subaru telescope to measure a precise distance to
the explosion: 12.8 billion light-years. This is the most distant
explosion astronomers have ever seen. There are less than fifty other
known objects at such a great distance from Earth, and the farthest is
only a mere 50 million light years more distant. Most of these are
too faint for all but the largest of telescopes, so astronomers are
excited by the relatively bright explosion.
"This explosion occured at the edge of the known Universe," Kawai
enthused. "One day soon, gamma-ray bursts will let us see further
than ever before."
The remnants of such explosions fade away in a matter of days, so
cosmic explorers must be on their toes to catch them, UH astronomer
Paul Price explained. When his cell phone rang at 2 a.m., Price was
ready take charge of pointing IRTF and MAGNUM to the site of the
MAGNUM has a novel camera capable of taking visible and infrared
images simultaneously, allowing Price, UH astronomer Len Cowie and
University of Tokyo astronomers Yuzuru Yoshii and Takeo Minezaki to
estimate the distance to the explosion from its color, reddened by the
expansion of the Universe.
"It was immediately apparent from the images that we were looking at a
source at the frontier of space," Professor Cowie said. "It's so much
more distant than all the other gamma-ray bursts we've seen up until
This discovery comes less than a decade after scientists first
learned that the explosions were coming from beyond our own galaxy.
It wasn't even until three years ago that astronomers pieced together
the puzzle of what causes these tremendous explosions.
According to Price, gamma-ray bursts are the death shrieks of a
massive star, and where there are dying stars, there must be living
ones as well. "Because these explosions are so bright, this gives us
the opportunity to study stellar birth and death in the most distant
Universe in a manner we could only dream about a couple of years ago."
Normally astronomers study the early Universe through the light of
distant galaxies, or that generated by black holes steadily devouring
matter. But the remnants of the gamma-ray bursts outshine even the
most hungry of galactic black holes, allowing them to be seen across
Gamma-ray burst researchers around the world are hoping that this
success is a taste of things to come, and are hoping to be provided
with further opportunities to push past the frontier.
The Subaru telescope is Japan's largest optical-infrared telescope,
operated by the National Astronomical Observatory of Japan. The
MAGNUM telescope, run by the University of Tokyo, is a 2 metre
telescope on Haleakala dedicated to observing galaxies harboring black
holes. The 3.5 metre InfraRed Telescope Facility is operated for NASA
by the UH Institute for Astronomy.