Golden Eye: Webb Telescope's Giant Mirror Unveiled

Witness the glimmering heart of NASA’s largest-ever space telescope

The James Webb Space Telescope primary mirror is unveiled at NASA's Goddard Space Flight Center's clean room in Greenbelt, Maryland.

Credit: NASA/Chris Gunn

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Yesterday, for the first time since its complete assembly earlier this year, the 6.5-meter mirror of NASA’s James Webb Space Telescope was revealed in all its golden glory. For months, black covers have hidden each of the mirror’s 18 coffee-table-sized hexagonal segments, protecting them as engineers assembled and tested additional telescope components. Each of the segments is made of lightweight beryllium—a dull, gray, toxic metal. An atoms-thin layer of vaporized gold gives them their sunny appearance, and boosts the mirror’s reflectivity of infrared light. This will prove crucial for the telescope’s mission to observe the faint infrared glow of the universe’s first stars and galaxies when it launches in 2018.

Read more about James Webb in this recent in-depth feature.

Lee Billings is a science journalist specializing in astronomy, physics, planetary science, and spaceflight and is senior desk for physical science at Scientific American. He is author of a critically acclaimed book, Five Billion Years of Solitude: The Search for Life Among the Stars, which in 2014 won a Science Communication Award from the American Institute of Physics. In addition to his work for Scientific American, Billings’s writing has appeared in the New York Times, the Wall Street Journal, the Boston Globe, Wired, New Scientist, Popular Science and many other publications. Billings joined Scientific American in 2014 and previously worked as a staff editor at SEED magazine. He holds a B.A. in journalism from the University of Minnesota.

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