Astronomers have spotted the most distant object yet confirmed in the universe – a self-destructing star that exploded 13.1 billion light years from Earth. It detonated just 640 million years after the big bang, around the end of the cosmic "dark ages", when the first stars and galaxies were lighting up space.
The object is a gamma-ray burst (GRB) – the brightest type of stellar explosion. GRBs occur when massive, spinning stars collapse to form black holes and spew out jets of gas at nearly the speed of light. These jets send gamma rays our way, along with "afterglows" at other wavelengths, which are produced when the jet heats up surrounding gas.
The burst, dubbed GRB 090423 for the date of its discovery last Thursday, was originally spotted by NASA's Swift satellite at 0755 GMT.
Within an hour, astronomers began training ground-based telescopes on the same patch of sky to study the burst's infrared afterglow. Some of the first observations were made on Mauna Kea in Hawaii with the United Kingdom Infrared Telescope and the Gemini North telescope.
Other telescopes later measured the spectrum of the afterglow, revealing that the burst detonated about 13.1 billion light years from Earth. "It's the most distant gamma-ray burst, but it's also the most distant object in the universe overall," says Edo Berger of the Harvard-Smithsonian Center for Astrophysics, a member of the team that observed the afterglow with Gemini North.
The object is a gamma-ray burst (GRB) – the brightest type of stellar explosion. GRBs occur when massive, spinning stars collapse to form black holes and spew out jets of gas at nearly the speed of light. These jets send gamma rays our way, along with "afterglows" at other wavelengths, which are produced when the jet heats up surrounding gas.
The burst, dubbed GRB 090423 for the date of its discovery last Thursday, was originally spotted by NASA's Swift satellite at 0755 GMT.
Within an hour, astronomers began training ground-based telescopes on the same patch of sky to study the burst's infrared afterglow. Some of the first observations were made on Mauna Kea in Hawaii with the United Kingdom Infrared Telescope and the Gemini North telescope.
Other telescopes later measured the spectrum of the afterglow, revealing that the burst detonated about 13.1 billion light years from Earth. "It's the most distant gamma-ray burst, but it's also the most distant object in the universe overall," says Edo Berger of the Harvard-Smithsonian Center for Astrophysics, a member of the team that observed the afterglow with Gemini North.
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