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For the past decade, astronomers are waiting for a remarkable new instrument to enter the world. The James Webb Space Telescope will be launched 1 million miles beyond Earth's orbit, further than any other telescope, where it will be able to observe the deepest corners of the universe. Once there, it deploys a sun visor to protect special sensors that can detect images emitting the faint glow of far-infrared light. From its perch in space, the telescope will be able to see the objects farthest from the universe, including the stars that formed just after the Big Bang and whose light has just reached us.
But scientists will have to wait even longer to zoom in on Jupiter's big red spot, or to look for exoplanets encircling distant solar systems. On Wednesday, NASA officials released the findings of a review panel reviewing the construction and testing of the James Webb Space Telescope. There were a lot of problems – delicate propulsion valves damaged by improper cleaning solvent, loose screws (70 of them!) That got loose during a shake test – 600 million dollars and a delay of 18 months. Cumulatively, the project has now been delayed for three years, costing over $ 9.6 billion. And two of the screws are still missing.
"The complexity and difficulty can not be overstated," said Thomas Young, chairman of the review panel, during a call to reporters. "Too much optimism has been built into the calendar." Young, an aerospace executive, added that the new estimated launch date of March 30, 2021 badumes nothing else is going wrong. "No allowance has been made for additional problems," he said.
When it was conceived in the 1990s, James Webb was to be completed in 2007 for a paltry $ 500 million. When that amount reached $ 5 billion in 2011, a House committee voted to cancel the project. The Maryland Senator, Barbara Mikulski, secured the reinstatement of funding, provided that NASA guaranteed that it would not cost more than $ 8 billion.
Then, last year, things got out of hand. The review committee found problems in the testing and integration of the spacecraft and its large sunshade by prime contractor Northrop Grumman. These problems were the result of human errors, embedded systems, a lack of experience, excessive optimism and the overall complexity of many new systems, according to the report.
This is the first time that NASA has been designing and building both a visor and actively segmented telescope mirrors. The first time that a NASA spacecraft was shipped to French Guiana by the Panama Cbad boat for launch. NASA will pilot for the first time a European Ariane 5 rocket (which could become Ariane 6 by 2021). It's a lot of tasks without previous experience, says the report.
To make matters worse, NASA can not send an astronaut to the telescope to fix it if something goes wrong, it will be too far.
An outside expert who studies complex engineering systems says that more tests are not the answer to the telescope's problems. "I do not worry about the problems they found, I'm worried about those that they did not find before they were launched," said John Thomas, researcher at the Department of aeronautics and astronautics MIT. "Testing is not a quick fix and I do not think it will be enough. Even if funding was not a problem, it requires a rigorous and systematic review of the system and what can go wrong.
In fact, Young, of the review board, said that he only believed that at 80% that the launch date of 2021 would be successful. Delays now cost taxpayers $ 1 million a day.
For their part, NASA officials defended the investments in the project. "He will be able to see much further in space, much further back in time," said John Mather, the chief scientist at JWST. "He will be able to look inside the clouds of dust where the stars are born, to see the planets around other stars pbading by their stars.There are so many wonderful things we are waiting for of this new observatory could have done before. "
To be sure, the JWST is a big improvement to the 28-year-old Hubble Telescope. But the problem with Hubble – like the fuzzy mirror that had to be replaced after it was launched into space – now seems to haunt the Webb, named for NASA's administrator during the Apollo years .
The $ 8 billion spending ceiling imposed by Congress has just climbed $ 800 million. And this figure does not even include the cost of running the project for five years, bringing the total bill to $ 9.66 billion. NASA's new director, Jim Bridenstine, will have to travel to Capitol Hill to ask for extra money. He is scheduled to appear before the House's scientific committee in July to explain the report to Northrup Grumman's leaders.
Meanwhile, dozens of engineers from NASA's Goddard Spaceflight Center in Maryland are being transferred to the Northrop plant in Redondo Beach, CA, to oversee more thoroughly the work of JWST by private contractors. . They should be prepared for a long stay. The project – and a muscular Congress – probably can not handle more cleaning problems.
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