A COSMIC hit-and-run accident, it happened long ago in a distant corner of the universe.
The Hubble space telescope, back in action after being shut down for a month by a technical glitch, has beamed back a snapshot of the wreckage left where two galaxies collided more than 400 million light years away.
The pinkish galaxy on the left scored a bullseye when it smashed through the bluish one on the right. Relatively undamaged, the culprit kept on going, hurtling away from the crash scene.
The victim was battered. The impact, Hubble scientists say, sent shockwaves rolling out from the centre of the damaged galaxy, "just as a pebble thrown into a pond creates an outwardly moving circular wave, or ripples".
Gas and dust swept out from the galaxy’s middle by the shockwaves slammed into matter from its outer edge that was collapsing into the centre.
The colliding waves of matter compressed the galaxy into a ring, which began glowing blue as its gas and dust condensed to give birth to stars.
"The reddish knot at the lower left of the blue ring probably marks the location of the original nucleus of the galaxy that was hit," Hubble scientists announced in a statement.
The astronomers have dubbed the picture the "perfect 10", partly because of the odd appearance of the pair of galaxies, known as Arp 147, and partly because of the ageing telescope’s performance.
Launched in 1990, Hubble was shut down in September by a fault in its control system that left it unable to store pictures or beam them back to Earth. However, after weeks of effort, Earth-bound engineers managed to coax the telescope back to life.
The galactic collision was photographed last week, just days after Hubble was fixed.
Space shuttle astronauts are training for a repair mission, scheduled for May, during which Hubble’s ailing electrical systems will be replaced and science instruments will be installed.