After a quarter-century of development, NASA’s James Webb Space Telescope is a smashing success. But senior project scientist John Mather, a Nobel-winning physicist who’s played a key role in the $10 billion project since the beginning, still sees some room for improvement.
Mather looked back at what went right during JWST’s creation, as well as what could be done better the next time around, during a lecture delivered today at the American Astronomical Society’s winter meeting in Seattle.
The seeds for JWST were planted way back in 1989, a year before the launch of the Hubble Space Telescope. Mather said the scientists who were planning for what was initially known as the Next Generation Space Telescope took a lesson from the problems that plagued Hubble — problems that required an on-orbit vision correction.
“No. 1 lesson from Hubble program was, figure out how you’re going to do this before you do it, and make sure the technologies are mature,” he said.
The JWST team designed a segmented mirror that could be folded up for launch, and then unfolded in space to create a 21-foot-wide reflective surface. An even wider sunshade blocked out the sun’s glare as the telescope made its observations from a vantage point a million miles from Earth.
Mather cycled through the new space telescope’s greatest hits — including a deep-field view with a gravitational-lensing galaxy cluster that brought even more distant objects into focus. “There is actually a single star which is magnified enough that you can recognize it in the image,” Mather said. “When we talked about this in the beginning, I thought the odds of this happening are too small. … I am completely stunned with this result.”