Scientist Researchers Peter Behroozi and Molly Peeples, both of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, have suggested Earth-like planets are let to develop.
But when they do, humans will be seen as the aliens in the galaxy that a new extra-terrestrial species from another world will seek out.
Although star formation has slowed down across the universe, and the amount of gas needed to form new stars in our galaxy the Milky Way is depleted, there is ample left out there.
The two calculated only 8% of potentially life-bearing worlds had formed at the same time or before Earth, meaning there is scope for the other 92% to develop.
Our main motivation was understanding the Earth’s place in the context of the rest of the universe. Compared to all the planets that will ever form in the universe, the Earth is actually quite early.
Ms Peeples added: “There is enough remaining material (since the Big Bang) to produce even more planets in the future, in the Milky Way and beyond.Locklip