London: Despite years of searching, scientists have long been perplexed on how there has been no confirmation of life beyond our planet. But now some astronomers state that the destructive force of exploding stars might have wiped out aliens.

In particular, a phenomenon known as a white dwarf hypernova could have sucked alien life into a black hole, they believe.

When a large white dwarf star, becomes unstable and explodes, it is called hypernova which scientists believe might have occurred a number of times over millions of years ending the alien life completely, a newspaper reported.

Hypernovas are considered as the explosion of all hypergiants, or stars with a solar mass of between 100 and 300 times that of the sun.

A decaying isotope of nickel is believed to provide much of a hypernova's light. A more impressive light show yet is produced when two collapsing white dwarfs, each the size of Earth, merge.

The process also produces the phenomenon known as a stellar-mass black hole, a permanent giant gap in the galaxy.

The collapse of a star is a natural process that occurs when all stellar energy sources are exhausted.

If the mass of the collapsing part of the star is below a certain critical value, the end product is a compact star, either a white dwarf or a neutron star.

But if the collapsing star has a mass exceeding this limit, the collapse will continue forever and form a black hole and astronomers believe that any collapsing star with solar mass above 0.7 will form a black hole.

They also believe there is possibility that life on Earth too could be wiped out by the process of gamma ray bursts.

It is possible that such a phenomenon may occur "soon" on the timescales familiar to astronomers, said Dr Edward Sion from Villanova University in Pennsylvania.