Circumstellar habitable zone

SUPER-EARTH LHS 1140B

Only a few decades ago, the thought of any alien planets existing in the reaches of space were just hypothetical ideas. Now, we know of thousands of such planets – and today, scientists may have discovered the best candidate yet for alien life.

Only 39 light-years away, astronomers have found seven planets circling a very small "red dwarf" star called Trappist-1. All seven are in or near what we call the "Goldilocks zone": Not too hot, not too cold, but just right for water to remain liquid on the planet. So we all speculate once again, but a little more bravely this time, about whether some of these planets might be home to life.

Astronomers hunting for another Earth have found the closest match yet, a potentially rocky planet circling its star at the same distance as our home orbits the Sun, NASA said July 23.

The Milky Way galaxy may be home to billions of planets orbiting their host stars in a "habitable zone" where life could theoretically exist, researchers said Wednesday.
      

Earth has a few more near-twin planets outside our solar system, tantalizing possibilities in the search for extraterrestrial life.
     
Astronomers announced Tuesday that depending on definitions, they have confirmed three or four more planets that are about the same size as Earth and are in the not-too-hot, not-too-cold "Goldilocks Zone" for liquid water to form.