Spaceflight Now’s Stephen Clark speaks to astronaut, astronomer and former NASA science head, John Grunsfeld about the upcoming launch of the James Webb Space Telescope. What big discoveries is he expecting from JWST? Is he nervous about the complex process to unfold the telescope in space? Why did his efforts to prepare JWST for possible servicing fail?

As an astronaut, Grunsfeld made three visits to service the Hubble Space Telescope in orbit. He served as the Deputy Director of the Space Telescope Science Institute where he helped prepare for JWST operations and then served as associate administrator for the Science Mission Directorate at NASA’s headquarters.

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