Astronomers at NASA have spent the last two years scouring the Milky Way for Earth-like planets in their quest for foreign life forms. And they have found 1,235 planets orbiting their suns, reports the Daily Mail.
The new estimate is based on data from NASA's Kepler space telescope. Of these candidate planets, there are 54 where life could possibly exist in the ‘Goldilocks Zone’.
The 'Goldilocks Zone' is the distance from a star where an Earth-like planet can maintain liquid water and Earth-like life on its surface. They would use the one-four-hundredth of the night sky that Kepler is looking at and extrapolate from there. Scientists figured one of two stars has planets and one of 200 stars has planets in the habitable zone.
And that’s a minimum because these stars can have more than one planet and Kepler has yet to get a long enough glimpse to see planets that are further out from the star, like Earth, said NASA space scientist William Borucki.
For example, if Kepler were 1,000 light years from Earth and looking at our sun and noticed Venus passing by, there''s only a one-in-eight chance that Earth would also be seen, said astronomers.
To get the estimate for the total number of planets, scientists then took the frequency observed already and applied it to the number of stars in the Milky Way.
For many years scientists figured there were 100 billion stars in the Milky Way, but last year a Yale scientist figured the number was closer to 300 billion stars.
The findings were presented at the American Association for the Advancement of Science annual conference in Washington last week.