It could have gone a very different way, as astronomers are well aware. "It wasn't one of those things, 'You know it would've been great if we could have done that, but it's getting pretty tough out there let's just quit.'" "They really picked the right mission, and so during the darkest days, it was still worthy of doing," he said. Turner, who was among the astronomers who stepped in to argue the telescope's case during the crisis, said that the very vision that saw JWST spiral out of control may also have saved the mission. The House of Representatives produced a budget proposal that would have ended work on the observatory, although by the end of budget negotiations the telescope survived. "They'd gotten themselves in trouble."Ĭongress lashed out. "People knew there was a problem, but no one wanted to say it," Turner said of NASA and JWST leadership. While substantial parts of the observatory were in the late stages of assembly, the project was still deep in debt and far from the launch pad. Related: The Hubble Space Telescope and 30 years that transformed our view of the universe All mistakes are stupid retrospectively." "It turns out there's no such thing as a smart accident," Turner said. Those tests caused delay after delay as engineers caught and caused issues in the observatory that needed to be fixed. "That's why you build in all the tests, because when it's that complicated, something's gonna go wrong," Turner said. NASA's fear of failure also perhaps contributed to JWST's troubled image, as engineers tested it every way they could. "But to mitigate the risk of failure, you really need a lot of time and labor, and it's not the materials that drive the cost of missions, it's actually labor." That's particularly true of aspects like project management and system management, that are key for staying on track, she noted. "If you have a large, complicated mission, you're going to demand high reliability because it's so expensive and you have so much riding on it," Frank said. "The more you try to do with one spacecraft, the more inherent technical complexity there is within the spacecraft," Frank said.Īnd as JWST became ever more ambitious, NASA became ever more determined to make sure nothing could go wrong. When the astronomy community began toying with ideas for what is now known as JWST in the 1990s, NASA leadership led by then-administrator Dan Goldin encouraged going bigger and bolder.įrom there, the ignominy JWST has faced over its ballooning budgets and ever-more-delayed launch may have been a little inevitable. (Image credit: NASA) An ever-growing project "If it weren't complicated, if it weren't at L2, if it hadn't had a sunscreen to keep it nice and cool, you couldn't do all the transformational stuff," Turner said.Īn animation shows the orbit of the James Webb Space Telescope around Lagrange point 2, or L2. Getting a spacecraft to L2, that's been done, but only by much smaller missions, like NASA's Wilkinson Microwave Anisotropy Probe that operated from 2001 to 2010 and the European Space Agency's Planck mission to map the cosmic microwave background.Īnd there's no way to simplify JWST and get science results of the same magnitude. Not so for JWST.Īnd JWST's mirror is too big to launch in one piece, so for the first time on a space telescope, it must align 18 different segments to form one perfectly smooth surface.Īnd the five-layer sunshield that must unfurl in space? Nothing like it has flown before. The Hubble Space Telescope, a smaller telescope but the key predecessor in scale to JWST, had a safety mechanism built in: Thanks to its orbit around Earth and its careful design, astronauts could visit the spacecraft and tend to its instruments. "When you're doing something for the first time, it's really hard to predict how long it's going to take and how much it's going to cost," Elizabeth Frank, who was a planetary scientist working on NASA missions before becoming chief scientist at First Mode, an engineering company, told. When designs for JWST solidified, NASA had never built anything like it before. Scientifically, it's all very exciting, but in terms of engineering, it's incredibly hard. So JWST has been given an unprecedented sunshield and the observatory will be sent to a spot called Earth-sun Lagrange point 2, or L2, 1 million miles (1.5 million kilometers) farther away from the sun than Earth. But infrared light is particularly difficult to observe because it doubles as heat.
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