London: For the first time, astronomers have observed a stunning cosmic jet from a super-massive black hole which shredded and then swallowed a luckless star.

The extremely rare phenomenon caused by stellar debris being consumed by the hole has never been observed before. It is known as "relativistic jets" and can reach hundreds of thousands of light years in length.

According to scientists, most galaxies have super-massive black holes -- regions of space that suck in everything nearby with their strong gravitation pull - at their core with masses of millions or even billions of suns, the Daily Mail reported.

Scientists were first alerted to the latest phenomenon in March after NASA's Swift telescope detected several bursts of X-rays from a quiet patch of sky.

Closer observations by a team from the Pennsylvania State University and the Harvard-Smithsonian Center for Astrophysics in Massachusetts revealed that the bursts were the remnants of a star pulled apart when it came too close to a black hole located 3.9 billion light years away.

Dr David Burrows, from Pennsylvania State University which controls Swift, said chemical analysis of the bright flash's ultraviolet light show it comes from material being sucked into a black hole the size of a million suns.

Writing in Nature, the team said that the Swift satellite just happened to be in the path of the jet of star remains that were shot out at 99.5 per cent the speed of light.

"Incredibly, this source is still producing X-rays and may remain bright enough for the Swift satellite to observe into next year. It behaves unlike anything we've seen before," said Dr Burrows. The swallowing of a star by a black hole only happens once every one hundred million years in a galaxy. The black hole is now believed to be even more powerful because of the additional mass from the swallowed star.

The absorption of large mass such as stars or even other black holes is what gives black holes growth and spawn the existence of super-massive black holes.

According to scientists, super-massive black holes could contain up to billions of solar masses. By comparison, the sun is just one solar mass and the Earth is 1/332,950th of a solar mass.