GRB 080916C
Encyclopedia
GRB 080916C is a gamma-ray burst (GRB) that was recorded on September 16, 2008 in the Carina
constellation and detected by NASA
's Fermi Gamma-ray Space Telescope. It was the most powerful gamma-ray burst ever recorded. The explosion had the power of over 9,000 supernovae, and the gas jets emitting the initial gamma rays moved at a minimum velocity of 99.9999 percent the speed of light
, making this blast the most extreme recorded to date.
The energy comparison with a supernova ignores that most of the energy of a supernova is carried away in the neutrino burst. The total isotropic energy of GRB 080916C is estimated at (the oft quoted 4.9 times the sun’s mass turned to energy) and should be jet-corrected to a much lower actual energy output due to the narrow angular width of the actual bursting jet. Thus it would be significantly less than the energy of a supernova neutrino burst, but is about equal to the energy in a supernova’s material explosion. Also, the peak energy flux of GRB 080916C is significantly less than a number of other GRB’s, such as GRB 080319B
which peaked at nearly in visible light alone. However, the total energy flux of the very long duration GRB 080916C was higher than any other measured GRB to date.
The 16.5-second delay for the highest-energy gamma ray observed in this burst is consistent with some theories of quantum gravity
, which state that all forms of light may not travel through space at the same speed. Very-high-energy gamma rays may be slowed down as they propagate through the quantum turbulence
of space-time.
The explosion took place 12.2 billion light-year
s (light travel distance) away. That means it occurred 12.2 billion years ago—when the universe was only about 1.5 billion years old. The burst lasted for 23 minutes, almost 700 times as long as the two-second average for high energy GRBs. Follow-up observations were made 32 hours after the blast using the Gamma-Ray Burst Optical/Near-Infrared Detector
(GROND) on the 2.2 metre telescope at the European Southern Observatory
in La Silla, Chile
, allowing astronomers to pinpoint the blast’s distance to 12.2 billion light years.
Carina (constellation)
Carina is a constellation in the southern sky. Its name is Latin for the keel of a ship, and it was formerly part of the larger constellation of Argo Navis until that constellation was divided in three.-Stars:...
constellation and detected by NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
's Fermi Gamma-ray Space Telescope. It was the most powerful gamma-ray burst ever recorded. The explosion had the power of over 9,000 supernovae, and the gas jets emitting the initial gamma rays moved at a minimum velocity of 99.9999 percent the speed of light
Speed of light
The speed of light in vacuum, usually denoted by c, is a physical constant important in many areas of physics. Its value is 299,792,458 metres per second, a figure that is exact since the length of the metre is defined from this constant and the international standard for time...
, making this blast the most extreme recorded to date.
The energy comparison with a supernova ignores that most of the energy of a supernova is carried away in the neutrino burst. The total isotropic energy of GRB 080916C is estimated at (the oft quoted 4.9 times the sun’s mass turned to energy) and should be jet-corrected to a much lower actual energy output due to the narrow angular width of the actual bursting jet. Thus it would be significantly less than the energy of a supernova neutrino burst, but is about equal to the energy in a supernova’s material explosion. Also, the peak energy flux of GRB 080916C is significantly less than a number of other GRB’s, such as GRB 080319B
GRB 080319B
GRB 080319B was a remarkable gamma-ray burst detected by the Swift satellite at 06:12 UTC on March 19, 2008. The burst set a new record for the farthest object that could be seen with the naked eye; it had a peak apparent magnitude of 5.8 and remained visible to human eyes for approximately 30...
which peaked at nearly in visible light alone. However, the total energy flux of the very long duration GRB 080916C was higher than any other measured GRB to date.
The 16.5-second delay for the highest-energy gamma ray observed in this burst is consistent with some theories of quantum gravity
Quantum gravity
Quantum gravity is the field of theoretical physics which attempts to develop scientific models that unify quantum mechanics with general relativity...
, which state that all forms of light may not travel through space at the same speed. Very-high-energy gamma rays may be slowed down as they propagate through the quantum turbulence
Quantum turbulence
Quantum turbulence is the name given to the turbulent flow - the chaotic motion of a fluid at high flow rates - of quantum fluids, such as superfluids which have been cooled to a fraction of a degree above absolute zero.-Introduction:...
of space-time.
The explosion took place 12.2 billion light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s (light travel distance) away. That means it occurred 12.2 billion years ago—when the universe was only about 1.5 billion years old. The burst lasted for 23 minutes, almost 700 times as long as the two-second average for high energy GRBs. Follow-up observations were made 32 hours after the blast using the Gamma-Ray Burst Optical/Near-Infrared Detector
Gamma-Ray Burst Optical/Near-Infrared Detector
The Gamma-Ray Burst Optical/Near-Infrared Detector is an imaging instrument used to investigate Gamma-Ray Burst afterglows. It is operated at the MPI/ESO 2.2m telescope at the La Silla Observatory.- Discoveries :...
(GROND) on the 2.2 metre telescope at the European Southern Observatory
European Southern Observatory
The European Southern Observatory is an intergovernmental research organisation for astronomy, supported by fifteen countries...
in La Silla, Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
, allowing astronomers to pinpoint the blast’s distance to 12.2 billion light years.
External links
- Most Powerful Gamma-Ray Burst May Point to New Physics, Sky and Telescope, February 19, 2009
- Fermi Observations of High-Energy Gamma-Ray Emission from GRB 080916C, ScienceScience (journal)Science is the academic journal of the American Association for the Advancement of Science and is one of the world's top scientific journals....
, February 19, 2009 - Most Extreme Gamma-ray Blast Ever, Seen By Fermi Gamma-ray Space Telescope, Science DailyScience DailyScience Daily is a news website for topical science articles. It features articles on a wide variety of science topics including: astronomy, exoplanets, computer science, nanotechnology, medicine, psychology, sociology, anthropology, biology, geology, climate, space, physics, mathematics,...
, February 19, 2009 - Telescope spies cataclysmic blast, BBC NewsBBC NewsBBC News is the department of the British Broadcasting Corporation responsible for the gathering and broadcasting of news and current affairs. The department is the world's largest broadcast news organisation and generates about 120 hours of radio and television output each day, as well as online...
, February 20, 2009 - NASA's Fermi Telescope Sees Most Extreme Gamma-ray Blast Yet, NASANASAThe National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
, February 19, 2009 - New telescope finds strange behavior in gamma-ray bursts, and also documents the most energetic burst known, Science NewsScience NewsScience News is an American bi-weekly magazine devoted to short articles about new scientific and technical developments, typically gleaned from recent scientific and technical journals. Science News has been published since 1922 by Society for Science & the Public, a non-profit organization...
, February 20, 2009 - Huge gamma-ray blast spotted 12.2 bln light-years from earth, AFPAgence France-PresseAgence France-Presse is a French news agency, the oldest one in the world, and one of the three largest with Associated Press and Reuters. It is also the largest French news agency. Currently, its CEO is Emmanuel Hoog and its news director Philippe Massonnet...
, February 19, 2009 - Fermi’s record breaking gamma-ray burst, Astronomy NowAstronomy NowAstronomy Now is a monthly British magazine on astronomy and space. It features a mix of articles ranging from how to observe the night sky to the latest discoveries in the Solar System and in deep space. The first issue of Astronomy Now was published in April 1987 by Intra Press, initially as a...
, February 20, 2009 - Record Cosmic Explosion Brightens Student's First Day, Newswise, February 19, 2009