5 Years of Swift

Gamma Ray Bursts are know to be the biggest bangs since the big bang! And NASA's Swift space telescope celebrated 5 years of observing these bursts just a few days ago - it was launched on November the 20th, 2004.

And as with most space telescopes, British astronomers play a key role.

Scientists at the University of Leicester designed the X-ray telescope on-board, built the X-ray camera's, and continue to calibrate and monitor its health. Leicester also hosts the UK Swift Science Data Centre. The Mullard Space Science Laboratory, part of the University College London, helped build the Ultra-violet and optical telescope.

UK scientists at both Leicester and MSSL are also on call throughout the day and night for when a burst goes off, to assess whether to follow up the observation with larger ground-based telescopes. Such decisions need to be made within minutes. A full list of UK-based scientists involved in the Swift Space Telescope can be found here on Swift's UK website.

The key thing about Swift is that it is, well, swift! Swift can detect a burst of gamma-rays occurring in about a quarter of the entire sky, and then automatically and rapidly (within 30 seconds!) turn around to scrutinise the rapidly fading explosion with its other on-board telescopes (the X-ray and optical telescopes).

There are two types of gamma-ray bursts - short bursts that last on average about 0.3 seconds, and the long bursts that on-average last about 30 seconds.

Before Swift, scientists knew very little about the short bursts (for obvious reasons... they happened too quickly!), and Swift was the first telescope to discover where these quick explosions were coming from. While scientists are still unsure as to what causes them, the leading idea is that they originate from the mergers of binary neutron stars.

The longer bursts are usually seen to occur with a supernova, which unambiguously links long bursts to the deaths of massive stars... although, strangely, some relatively nearby long bursts appear to have no accompanying supernova. As is often the case in science, when one mystery is solved, another appears!

And because these burst of gamma-rays are the biggest explosions known to man, we can see very distant bursts. The most distant object known, pictured here, is a Gamma-ray burst seen by Swift (see this BBC News story).