11 November 2009
A group of astronomers, including UvA professor Ralph Wijers, recently published two papers in Nature on the most distant astronomical object to be discovered so far in the universe: gamma-ray burst GRB 090423.
GRB 090423 was detected by NASA's Swift satellite on 23 April 2009. Within a few minutes, several of the world's largest telescopes were able to locate the rapidly fading afterburner. The afterburner was exclusively visible in the infrared spectrum, indicating that the gamma-ray burst had emanated from an extremely distant point in space. Two teams measured an 8.2 redshift, indicating that the universe was at a mere 5% of its current age at the time of the gamma-ray burst. The record for most distant object was previously held by a galaxy with a redshift of 6.96.
Tanvir, N., et al, Nature 461, 1254-1257 (2009)
For more information, please contact Prof. Dr Ralph Wijers, email: R.A.M.J.Wijers@uva.nl.