The Search for Another Earth

This artist’s impression shows the planet orbiting the Sun-like star HD 85512 in the southern constellation of Vela (The Sail). This planet is about 3.6 times as massive as the Earth and lies at the edge of the habitable zone around the star, where liquid water, and perhaps even life, could potentially exist.

Twenty years ago astronomers discovered the first planet around a Sun-like star, 51 Pegasi b. And in the last 20 years, astronomers have discovered thousands of new exotic worlds, begun to characterize atmospheres of faraway planets, and are developing cutting-edge technology to launch us on our search for alien life. Planets with two suns, rogue planets with no star, close cousins to planet Earth. This is the story of the pioneers in planet-hunting and how those who have followed are now poised to answer one of humanity’s most ancient questions: is there life elsewhere in the Universe?

Image Credit: ESO/M. Kornmesser/Nick Risinger
Explanation from: https://www.eso.org/public/images/eso1134a/ and https://exoplanets.nasa.gov/resources/1080/