Latest Gamma-ray burst progenitors Stories
Cosmic explosions known as gamma-ray bursts are curiously picky about where they explode. Shunning spiral galaxies like the Milky Way, gamma-ray bursts prefer to 'go off' in oddball star systems that astronomers are just beginning to understand.
For decades it was baffling. Out of the still night sky, astronomers peering through their telescopes would occasionally glimpse quick bursts of high-energy light popping off like flashbulbs at the far side of the universe.
ESAâ€™s Integral gamma-ray observatory has observed several low-luminosity gamma-ray bursts, confirming the existence of an entire population of weaker bursts hardly noticed so far.
By Luntz, Stephen A beautiful star system may eventually be a threat to Earth, although its discoverer stresses that the risk is small. Wolf-Rayet stars are considered the time bombs of the galaxy, likely to explode as supernovae in astronomically short timescales.
With eyes that peer into the most energetic phenomena in the universe, ESAâ€™s Integral has been setting records, discovering the unexpected and helping understanding the unknown over its first five years.
Astronomers have for the first time measured the velocity of the explosions known as gamma-ray bursts. The material is travelling at the extraordinary speed of more than 99.999% of the velocity of light, the maximum speed limit in the Universe.
Using NASAâ€™s Swift satellite, astronomers have discovered that energetic flares seen after gamma-ray bursts (GRBs) are not just hiccups, they appear to be a continuation of the burst itself.
A survey of galaxies observed along the sightlines to quasars and gamma-ray bursts--both extremely luminous, distant objects--has revealed a puzzling inconsistency. Galaxies appear to be four times more common in the direction of gamma-ray bursts than in the direction of quasars.
Are you losing sleep at night because you're afraid that all life on Earth will suddenly be annihilated by a massive dose of gamma radiation from the cosmos? Well, now you can rest easy.
Gamma-ray bursts are the most powerful explosions in the universe, emitting huge amounts of high-energy radiation. For decades their origin was a mystery. Scientists now believe they understand the processes that produce gamma-ray bursts.
Hypernova -- A hypernova is a theoretical type of supernova produced when exceptionally large stars collapse at the end of their lifespan. In a hypernova, the core of the star collapses directly into a black hole and two extremely energetic jets of plasma are emitted from its rotational poles at nearly light speed. These jets emit intense gamma rays, and are a candidate explanation for gamma ray bursts. Theorists have come up with several plausible explanations for hypernovae. It may...
Gamma-Ray Burst -- In astronomy, Gamma-ray bursters (GRBs) are flashes of gamma rays that last from seconds to hours, the longer ones being followed by several days of X-ray afterglow. They occur at random positions in the sky several times each day. They are now believed to result from tremendous explosions in far away galaxies, during the creation of a black hole from a dying star or two colliding neutron stars. The black hole, surrounded by a rotating disk of matter falling into it,...