This is the period of time when signs are visible before a gamma ray burst
Gamma ray bursts - occult flashes charged with tremendous energy of light - which are the most powerful explosions occurring in the universe - an early warning time of only 10 seconds. Their "violent" power is equal to the immense energy of the neutrino particles.
Neutrinos are almost massless matter particles that move through the universe unnoticed, but they penetrate through regions of space that "choke" gamma rays and forms of light. They seem to carry with them information about the very first stars that formed in the universe.
This fact about neutrinos and gamma rays may help scientists count the number of most massive stars that have collapsed and become black holes. Many of those collapsed stars lack the signature of gamma radiation and other radiation but the neutrinos thrive in them.
A new theory on this topic was completed these days by two scientists, Eli Waxman from the Weizmann Institute and his colleague Peter Mazarus from the University of Pennsylvania in the USA and it was published last week in the journal "Physical Review Letters".
Gamma radiation bursts occur once a day and last a few seconds, but it is difficult to detect and analyze them because most of them occur at cosmological distances, billions of light years from the Earth, another time when the universe was very young. Sixty-fourths of gamma ray bursts are born from a fireball that forms when the core of a star, at least 25 times more massive than the Sun, collapses and becomes a black hole.
The oldest gamma ray burst has been discovered
It happened about 11 billion years ago in the early universe and its light, as well as the gamma radiation of the explosion, reached space and terrestrial telescopes that observed it this year.
18/7/2001
Echoes of a cosmic explosion that occurred 11 billion years ago could give scientists a new way to measure the age of celestial bodies. This is what astronomers reported on 18/7/2000.
The explosion, known as a gamma-ray burst, was observed in January of this year and it took 8 months to locate where it came from: GRB 000131 in the southern star system Carina (Shipwreck). Before that, the oldest previous eruption was 9 billion years old. The observations were made by a cluster of interstellar spacecraft and revealed that the gamma ray bursts come from a giant dying star 30 times more massive than the Sun.
Their findings were presented in Rome at an international meeting dealing with gamma-ray bursts - high-energy light flashes that occur about once a day. Their cause is still unknown, but they are the most powerful explosions in the known universe, says Kevin Hurley, a physicist at the University of California, Berkeley, and principal investigator of gamma-ray bursts on NASA's Ulysses findings research team.
The explosion that the scientists discovered is 11 billion light years away, a light year is about 10 trillion kilometers - the distance that light travels in a year. "The light from this tiny flash traveled for 11 billion years before reaching Earth and testified to an event that is one of the most distant we have observed and studied, in any galaxy in the early universe," Harley said.
Gamma ray bursts cannot be observed from the Earth because the atmosphere absorbs the weak light coming from them, but special spacecrafts designed for this can detect traces of gamma radiation reaching the Earth, and indicate where they come from. Astronomers using the European Space Agency's massive telescope in Chile found that the same eruption also had a visible-light signature, and they also suggest the possibility that it came from a great distance away.
The network of spacecraft that discovered the eruption includes Ulysses operated jointly by NASA and the European Space Agency, the NEAR spacecraft (currently orbiting the asteroid Eros), and the Italian Bepposax spacecraft.
