https://www.wired.com/story/nasas-biggest-telescope-ever-prepares-2021-launch/

If you were a rogue bee buzzing on the moon, this heat-detecting honeycomb could find you. But rest easy, tiny friend: The $10 billion James Webb Space Telescope will have bigger concerns. Once it is blasted into orbit in 2021, it will seek out water on Earth-like planets, stars being born, and remote objects formed in the first 100 million years after the Big Bang.

Webb's precision comes from its 21.3-foot primary mirror, nearly three times as big as Hubble's. Its folding, hivelike design is formed by 18 lightweight beryllium hexagons that work as one; to sharpen focus, 126 small motors pivot these segments in increments as small as one ten-thousandth the width of a grain of lily pollen. They collect 269.1 square feet of light, 50 times more than NASA's current infrared space telescope, Spitzer. A gold coating enhances the mirror's reflection of long-wave light, including infrared radiation created 13.6 billion years ago, further back than any telescope has ever seen. “The telescope is a time machine,” says Nobel laureate and lead scientist John Mather. “You see things as they were when light was sent out.”