Life on Earth was born prematurely and this new hypothesis is being used to explain why we haven't found signs of intelligent life in the Universe despite searching for it for over half a century.

Put in another way, this theory by Avi Loeb of the Harvard-Smithsonian Center for Astrophysics says we're probably the most intelligent life form out there. But again, there are parallel Universes that just might be inhabited by life forms more technologically advanced than ours.

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Loeb's new theory suggests life on Earth is actually premature from a cosmic perspective, that is.

"If you ask, 'When is life most likely to emerge?' you might naively say, 'Now,'" said Loeb.

"But we find that the chance of life grows much higher in the distant future."

What scientists agree on is that life as we know it first became possible after the first stars seeded the cosmos with life-giving elements like carbon and oxygen some 30 million years after the Big Bang, which took place 13.8 billion years ago. Many scientists also agree life will end 10 trillion years from now when the last stars fade away and die.

Loeb and his colleagues considered the relative likelihood of life between these two boundaries.

The dominant factor proved to be the lifetimes of stars. The higher a star's mass, the shorter its lifetime. Stars larger than three times the sun's mass will die before life on their planets has a chance to evolve.

Conversely, the smallest stars weigh less than 10 percent as much as the Sun. They will glow for 10 trillion years, giving life ample time to emerge on any planets they host.

As a result, the probability of life grows over time. In fact, the chances of life are 1,000 times higher in the distant future than now.

"So then you may ask, why aren't we living in the future next to a low-mass star?" says Loeb.

"One possibility is we're premature. Another possibility is that the environment around a low-mass star is hazardous to life."

Although low-mass, red dwarf stars live for a long time, they also pose unique threats. In their youth they emit strong flares and ultraviolet radiation that could strip the atmosphere from any rocky world in the habitable zone.

To determine which possibility is correct -- our premature existence or the hazard of low-mass stars -- Loeb recommends studying nearby red dwarf stars and their planets for signs of habitability.

Future space missions like the Transiting Exoplanet Survey Satellite and James Webb Space Telescope should help to answer these questions.

Tagslife, Earth, Avi Loeb, Harvard-Smithsonian Center for Astrophysics