New York, Jun 15:  We are unlikely to hear from aliens from across the universe for at least 1,500 years more, even though there may be other life forms in the cosmos, scientists say. “We haven’t heard from aliens yet, as space is a big place  but that doesn’t mean no one is out there,” said Evan Solomonides, from the Cornell University in the US.Also Read - UFO or Satellite Crash? Mysterious Meteor Falls to Earth With Massive Explosion in Turkey, Turns Sky Green | Watch

“It’s possible to hear any time at all, but it becomes likely we will have heard around 1,500 years from now,” said Solomonides. “Until then, it is possible that we appear to be alone – even if we are not. But if we stop listening or looking, we may miss the signals. So we should keep looking,” he said. Astronomers from Cornell University deconstructed the Fermi Paradox and paired it with the Mediocrity Principle into a fresh equation. According to the Fermi Paradox, billions of Earth-like planets exist in our galaxy, yet no aliens have contacted or visited us. Thus the paradox: the cosmos teems with possibility. (ALSO READ: Aliens spying on ISRO? Mysterious UFO sighted over ISRO centre) Also Read - Mysteriously Large Meteor Blazes Through Night Sky in Norway, May Have Hit Earth Near Oslo | Watch

The mediocrity principle – proposed by 16th-century mathematician Copernicus – states that the Earth’s physical attributes are not unique, as natural processes are likely common throughout the cosmos, and therefore aliens would not discover us for a while. Hunting for extraterrestrials means sending out signals like television broadcasts, for example. Also Read - Asteroid 3 Times The Size of Taj Mahal to Pass Close to Earth on July 25, Is It Dangerous?

As Earth’s electronic ambassador, TV and radio signals are sent into space as a byproduct of broadcasting. These signals have been travelling from Earth for 80 years at the speed of light. For aliens receiving these transmissions, they would likely be indecipherable, said Solomonides, as the extraterrestrials would need to decode light waves into sounds, then parse 3,000 human languages to grasp the message.

Earth’s broadcast signals have reached every star within about 80 light years from the Sun – about 8,531 stars and 3,555 Earth-like planets, as our Milky Way galaxy alone contains 200 billion stars, researchers said. Combining the equations for the Fermi Paradox and the mediocrity principle, the researchers suggest that the Earth might hear from an alien civilisation when about half of the Milky Way Galaxy has been signalled in about 1,500 years.