Mystery of short gamma ray bursts solved

  • This sequence illustrates the kilonova model for the formation of a short-duration gamma-ray burst. 1. A pair of neutron stars in a binary system spiral together. 2. In the final milliseconds, as the two objects merge, they kick out highly radioactive material. This material heats up and expands, emitting a burst of light called a kilonova. 3. The fading fireball blocks visible light but radiates in infrared light. 4. A remnant disc of debris surrounds the merged object, which may have collapsed to form a black hole. Image credit: Nasa, ESA and A Field (STScI)
  • These Hubble images show the fireball afterglow of Gamma-ray Burst 130603B Image credit: Nasa, ESA, N Tanvir (University of Leicester), A Fruchter (STScI) and A Levan (University of Warwick)
Date:5 August 2013 Tags:, , , ,

Nasa’s Hubble Space Telescope has detected a new kind of stellar blast called a kilonova, which happens when a pair of compact objects – such as neutron stars – crash together. Hubble observed the fading fireball from a kilonova last month, following a short gamma ray burst (GRB) in a galaxy almost 4 billion light-years from Earth.

“This observation finally solves the mystery of short gamma ray bursts,” says Nial Tanvir of the University of Leicester in the United Kingdom, who led a team of researchers conducting this research.

Many astronomers have provided evidence that long-duration gamma ray bursts are produced by the collapse of extremely massive stars; however, the cause of short gamma ray bursts has been a mystery – until now.

“We only had weak circumstantial evidence that short bursts [might be] produced by the merger of compact objects,” says Tanvir. “This result now appears to provide definitive proof.”

Kilonovas are about 1 000 times brighter than a regular nova, which is caused by the eruption of a white dwarf.

The team’s results appeared on 3 August in a special online publication of the journal Nature.

Credit: Science@Nasa

 

Latest Issue :

Nov-December 2021