Chris Gunn/NASA

Along with my fellow scientists, I’ve been dreaming and thinking about the James Webb Space Telescope since 1995. It’s the most important scientific project I could imagine working on—100 times more powerful than its precursor, the Hubble Space Telescope.

To me, Webb is an engineering miracle. It’s a people miracle too; over 10,000 scientists, engineers, and others worked on it. Who can we thank for Webb’s success, now that it’s up in space and taking sharp pictures just as we hoped?

Greg is our program director at NASA headquarters, and to build such an engineering marvel and scientific success, he channeled the forces of human nature and ingenuity: NASA, the U.S. House of Representatives and Senate, the European and Canadian space agencies, Northrop Grumman, the launch-vehicle company Arianespace in France, and the Space Telescope Science Institute, where we command the telescope. Our teams orbit around Greg, because we trust him to ask questions and understand our concerns and respect our opinions. He makes it look easy, but I can barely imagine how he does it, and I admire him tremendously for it.

Mather is an astrophysicist at NASA’s Goddard Space Flight Center and a Nobel laureate

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