Hunt for habitable exoplanets needs new telescopes, report says

To find out how rare our solar system is, a report from the U.S. National Academies of Sciences, Engineering & Medicine recommends NASA fund new space telescopes to directly observe planets orbiting distant stars and to identify the chemicals in those planets’ atmospheres. Astronomers know of more than 3,800 planets beyond our solar system, most discovered in the past decade, and NASA’s James Webb Space Telescope is expected to extend that search when it launches in the next several years. Nevertheless, the congressionally mandated report describes a “substantially incomplete” understanding of what kinds of exoplanets exist and how many there are of each type. The report’s suggested solution is a space-based, near-infrared telescope. As a first step, the report endorses NASA’s planned Wide Field Infrared Survey Telescope (WFIRST), which could demonstrate coronagraphic technology to block the brightest light from a star so orbiting planets become visible. A more powerful version could identify methane and other chemicals in an exoplanet’s atmosphere. And new ground-based telescopes planned and under construction can provide complementary chemical data about exoplanet atmospheres.