Cosmic blast in distant galaxy that has so far lasted for 11 DAYS puzzles scientists - 8th Apr 2011

Gamma-ray explosions normally last a couple of days

Reminiscent of a space invaders computer game from the early 1980s, this is actually a cosmic blast in a distant galaxy.

The extraordinary gamma-ray explosion was observed on March 28 by Nasa's Swift satellite.

It has left astronomers scratching their heads - because it has so far lasted an incredible 11 days.

Flaring from such an event usually lasts a couple of hours.

But scientists are perplexed by this blast because, unusually, the effects are so long-lasting.

More than a week later, they are continuing to see high-energy radiation spiking and fading at the source.

The burst was likely caused by a star that was ripped apart after drifting too close to a super-massive black hole. Read More