Intense light from the enormous explosion of a star 12.1 billion years ago -- shortly after the Big Bang -- recently reached Earth and was observed by a robotic telescope. Known as a gamma-ray burst, these rare, high-energy explosions are the catastrophic collapse of a star at the end of its life. Astronomers can analyze the observational data to draw further conclusions about the structure of the early universe.
Gamma-ray bursts are believed to be the catastrophic collapse of a star at the end of its life. SMU physicists report that their telescope was the first on the ground to observe the burst and to capture an image, said Farley Ferrante, a graduate student in SMU's Department of Physics, who monitored the observations along with two astronomers in Turkey and Hawaii.
Recorded as GRB 140419A by NASA's Gamma-ray Coordinates Network, the burst was spotted at 11 p.m. April 19 by SMU's robotic telescope at the McDonald Observatory in the Davis Mountains of West Texas.
Gamma-ray bursts are not well understood by astronomers, but they are considered important, Ferrante said.
"As NASA points out, gamma-ray bursts are the most powerful explosions in the universe since the Big Bang," he said. "These bursts release more energy in 10 seconds than our Earth's sun during its entire expected lifespan of 10 billion years."
Some of these gamma-ray bursts appear to be related to supernovae, and correspond to the end-of-life of a massive star, said Robert Kehoe, physics professor and leader of the SMU astronomy team.
"Gamma-ray bursts may be particularly massive cousins to supernovae, or may correspond to cases in which the explosion ejecta are more beamed in our direction. By studying them, we learn about supernovae," Kehoe said.
Scientists weren't able to detect optical light from gamma-ray bursts until the late 1990s, when telescope technology improved. Among all lights in the electromagnetic spectrum, gamma rays have the shortest wavelengths and are visible only using special detectors.