06/04/2013
NASA's Hubble Space Telescope has found the oldest, most distant supernova ever discovered, which experts say could help scientists better understand the evolution of the universe.
A supernova is the explosive death of a star, which emits a dramatic burst of light. This latest discovery, Supernova UDS10Wil, or SN Wilson, exploded more than 10 billion years ago, NASA said.
SN Wilson, named after President Woodrow Wilson, is categorized as a Type Ia supernova, which are prized astronomical finds because they provide a consistent level of brightness that can be used to measure the expansion of space.
Type Ia supernovas also offer clues to the nature of dark energy, a mysterious and largely unknown force thought to accelerate the expansion of the universe.
"This new distance record holder opens a window into the early universe, offering important new insights into how these stars explode," said David Jones, an astronomer at Johns Hopkins University. "We can test theories about how reliable these detonations are for understanding the evolution of the universe and its expansion."
NASA reported that the discovery came out of a three-year Hubble project that focused on studying distant Type Ia supernovae to determine whether they have changed during the 13.8 billion years since the birth of the universe.
Astronomers used Hubble's Wide Field Camera 3 to search for the supernovae and calculate their distance with spectroscopy.
The supernova discovery was aided by a 2009 repair and upgrade to the Hubble Space Telescope, which was launched in 1990 and orbits about 350 miles above the Earth's surface.
Astronauts on the space shuttle Atlantis, which carried 22,500 pounds of equipment for the telescope, spent 11 days restoring a broken-down, wide-field imaging camera, while also installing a new, more powerful one. They also did the same with Hubble's Space Telescope Imaging Spectrograph.
On the same trip, the astronauts replaced all six of the Hubble's gyroscopes and all six of its batteries, along with a computer unit that had failed months earlier.
During its 23 years in orbit, Hubble's discoveries have been so important that they have forced academics to rewrite astronomy text books. It has taken deep photographs of the universe and captured images of the birth and death of stars.
It also played a key role in discovering that the universe, believed to be driven by dark energy, is expanding at an accelerating rate. And Hubble also showed that most galaxies in the universe contain massive black holes.
At the time, NASA scientists said they thought the repairs and upgrades would keep the Hubble running until 2014, if not until 2016 or 2017.
