The Astronomer Who’s About to See the Skies of Other Earths

 We know next to nothing about the other 6 billion or so Earth-like planets in the galaxy. With the imminent launch of the largest, most powerful space telescope ever built, Laura Kreidberg is optimistic this will soon change.

Kreidberg is the 32-year-old founding director of a new department at the Max Planck Institute for Astronomy in Heidelberg, Germany, devoted to studying what the weather is like on alien worlds. So far, she and her team have scrutinized the atmospheres around Jupiter-size exoplanets (planets orbiting other stars). When it comes to small, rocky exoplanets that could potentially harbor life, current telescopes lack the resolving power to do much more than tally the number that are out there. But NASA’s $10 billion James Webb Space Telescope (JWST), set to launch in December after decades of planning and construction, will allow astronomers like Kreidberg to peer into rocky planets’ skies and, she said, “turn these planets into places.”

JWST’s distinguishing feature is a sunshield the size of a tennis court that will protect its instruments and gold-plated mirrors from the heat of the sun and Earth. Shaded in this way, the telescope will be able to detect faint infrared radiation, such as the light coming from exoplanets. Kreidberg is the lead investigator for two programs in JWST’s coveted first round of observations. Her projects seek evidence of atmospheres and volcanic activity around Earth-size worlds.

Kreidberg, who grew up in Reno, Nevada, has been a rising star among exoplanet scientists since completing her doctorate in astronomy and astrophysics at the University of Chicago in 2016. The overarching question motivating her research on exoplanet atmospheres — work for which she won the Annie Jump Cannon Award earlier this year — is whether alien life exists in the cosmos. “The universe feels profoundly lonely,” she said. Discovering aliens “would be comforting, in a strange way.” Scientists suspect that life cannot survive on skyless planets, so investigating atmospheres around rocky planets is a key step toward answering the “Are we alone?” question.

During our conversation, Kreidberg laid out the ingenious methods she’ll use to observe far-off, pinpoint planets orbiting in the blinding glare of their parent stars. Despite her calm and meticulous manner, her excitement about the new telescope bubbled over: “We’ve been waiting for this for so long!” The interview has been condensed and edited for clarity.