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NASA has delayed for 10 months the launch of its huge and long-awaited James Webb Space Telescope.
The takeoff of Webb, successor to the iconic Hubble Space Telescope, was postponed from May 2020 to March 2021, NASA officials announced today (27 June). The project's development cost has risen from $ 8 billion to $ 8.8 billion, and its total life cycle cost now stands at $ 9.66 billion, they added.
The rescheduling is the latest in a series of delays for Webb, which NASA had originally hoped to take off in 2007. [Photo Tour: Building NASA’s James Webb Space Telescope]
"We have to do this here on the ground before going into space," said Thomas Zurbuchen, badociate director of NASA's Science Missions Directorate, at a press conference. "And I just want to emphasize again: Webb is worth the wait."
The optical element of NASA's James Webb Space Telescope is removed from an expedition container in a Northrup Grumman clean room in March. The element of the spacecraft, including the folded sunshade, is left before undergoing an acoustic test.
Credit: Northrop Grumman
Rocky road for a complex observatory
Webb is a versatile observatory that will allow astronomers to study some of the first stars and galaxies in the universe, to look for any signs of life in the atmospheres of nearby alien planets and to discover the world. perform a variety of other prestigious work. Its primary mirror is 21.3 feet (6.5 meters) wide compared to Hubble's 7.8 feet (2.4 meters) wide.
"Webb is vital for the next generation of research beyond NASA's Hubble Space Telescope," NASA Administrator Jim Bridenstine said in a statement. "It's going to do incredible things – things we've never done before – as we look at other galaxies and see the light since the dawn of time."
Webb is optimized to see the sky in infrared light, and its instruments must be kept cool. Thus, the telescope will sport a giant sunshade the size of a tennis court, which will unfold after Webb has reached its final destination, a gravitationalally stable place at about 930,000 miles (1.5 million kilometers ) of the earth.
The road to this destination has been quite bumpy so far. Webb is a very complex observatory that has proven difficult to build and test for the main contractor Northrop Grumman, as evidenced by the repeated delays.
Until recently, NASA was aiming for a launch in October 2018. In September of last year, however, NASA announced that shipboard integration issues had delayed launching until the end of September. In the spring of 2019. Then, last March, the agency postponed the scheduled date of takeoff until May 2020. More time was needed to test Webb complex systems and deal with setbacks, such as as little tears in the visor, NASA officials said at the time.
The agency also set up an Independent Review Committee (IRB) in March to monitor the progress of the observatory and develop recommendations. The IRB reported to NASA on May 31 and the agency completed its response to this report yesterday (June 26). (You can read NASA's report and response here.)
The IRB traced the 29-month timeframe (from a targeted launch date of October 2018 to March 2021) to five factors: human error, "nested problems", excessive optimism, complexity of systems, and lack of information. Experience in key areas, such as visor development.
IRB President Tom Young outlined some of the most significant human errors at today's news conference. The technicians used the wrong solvent to clean the propulsion valves; used a bad wiring that caused excessive voltage to be applied to the transducers; and poorly installed sunshade clips before a key test, he said.
"All the simple repairs that have not been implemented have resulted in a delay of about a year and a half, at a cost of about $ 600 million," said Young, former director. from NASA's Goddard Space Flight Center in Greenbelt, Maryland. the operations officer of the airline Martin Marietta (which merged with Lockheed Corporation in 1995, forming Lockheed Martin).
Go from the front
The IRB's report played a key role in NASA's latest plan for Webb, officials at the agency said. Indeed, the review panel made 32 separate recommendations for the development of the observatory, of which 30 are fully in agreement with NASA, said Zurbuchen. (The agency still considers the other two, he added.)
Basically, the IRB has not recommended pulling the plug on the telescope.
"With all the factors I've discussed, the IRB believes that JWST should continue, because of compelling science, and because of the national importance of JWST," said Mr. Young.
The increase in mission development costs from $ 8 billion to $ 8.8 billion could, however, complicate this vision. The old number was a limit imposed by Congress, which means that Webb needs another approval from Capitol Hill to continue.
"We are submitting our final violation report to Congress this week," NASA Associate Administrator Steve Jurczyk told the press conference today. "And then, it is true that the Congress will have to reauthorize Webb through this next cycle of credits."
Follow Mike Wall on Twitter @michaeldwall and Google+. follow us @Spacedotcom, Facebook or Google+. Originally posted on Space.com.
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