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NASA's James Webb Space Telescope was supposed to be one million kilometers from Earth, peering deep into the universe and back in time to the assembly of stars into galaxies . But its launch is still years and billions of dollars, and the success of the mission depends on a lot of delicate things that are doing just fine. The telescope unfortunately has some loose screws.
And the pucks. And the nuts.
Technicians discovered that rogue screws fell during a test this spring. It was among several forehead and design mistakes that delayed until March 2021 the launch of the telescope, which has now cost taxpayers about $ 7.4 billion and whose cost is estimated at $ 9.7 billion.
The work of the Webb will be at the center of two days of testimony, starting Wednesday, before the scientific committee of the House. NASA's director Jim Bridenstine and Wes Bush, the chief contractor's chief executive, Northrop Grumman, will be among those who will appear and will likely face tough questions.
Webb problems have shaken many powerful groups. NASA is embarrassed and dismayed by the human errors that triggered its largest scientific project in robotics, identified by the astronomical community in 2000 as its top priority.
The US aerospace industry, which faces a wave of retirements, must prove to national leaders that it remains as competent as when it puts people on the moon. The same companies that build civilian space telescopes are also building spy satellites. Earlier this year, a satellite code of the Department of Defense filed Zuma was lost after failed to separate from a rocket booster . This satellite was built by Northrop Grumman.
An independent review committee report said this summer that Webb is potentially vulnerable to 344 different "one-time failures" – an extraordinary number for any mission. That means that if a single metal spacer breaks down or that only one cable is hooked, "we have a ten billion dollar clipboard," said astrophysicist Grant Tremblay of Harvard-Smithsonian Center for Astrophysics. Unlike the Hubble Space Telescope, the Webb can not be repaired in space. It will be placed more than four times farther from the Earth than the Moon.
Many young scientists rely on the Webb for essential research to advance their careers. But they also understand that it must be done correctly.
"We know that once this thing is in space, we can not fix it," said Victoria Scowcroft, an astrophysicist at the University of Bath in Britain. "We much prefer to wait for a telescope in the space that works than not to have one."
NASA reviews its scientific programs, Thomas Zurbuchen, a senior NASA scientist, at the Washington Post. errors? Zurbuchen said, "How many other mistakes are there?"
NASA officials have increased the oversight of Northrop Grumman.About a dozen NASA employees are integrated full-time at the Redondo Beach, California plant, and other NASA experts perform regular rotations.
Thomas Young, former NASA head, is confident that the project should go ahead, but with more care: "There must be a general effort to try to find additional problems."
Northrop Grumman, one of the largest contractors of the US government, expressed confidence with an operational telescope
"The success of the mission is the cornerstone of everything we do. It's very important to get it right, "said Scott Willoughby, program director at Webrop at Northrop Grumman. "No, we do not need a culture change We need people to understand how difficult it is We need people to know that we are going to do things correctly. "
The Webb is designed to see the oldest light in the universe. It can also detect the atmospheres of planets beyond our own solar system and search for the chemical signatures of life, such as an abundance of oxygen.
In doing this, the Webb will examine two of the most fundamental questions: Where did we come from? And are we alone?
The 6.5-meter-wide segmented mirror of the telescope must remain cool to observe infrared light. It must be kept in the shade by a sunshade, the size of a tennis court, which must deploy in the space.
Many components of Webb had to be invented from scratch: the vast, segmented main mirror, origami. -like the solar shield, the cryocooler that holds the ultrasensitive instruments a few degrees above absolute zero, the network of thousands of microshutters, thinner than the width of a human hair, which open and close to allow the light of the target objects to reach
The telescope will be shipped from California to French Guiana via the Panama Canal, and will leave the European Spaceport at the top of an Ariane rocket 5.
The telescope and its instruments were tested at NASA's Goddard Space. Flight Center at Greenbelt, Md., Then at NASA's Johnson Space Center in Houston, before being flown to Northrop Grumman at Redondo Beach. It is there that the telescope will be assembled with the sun visor and the subsystems that provide propulsion, electricity and other functions, and are collectively known as the bus. spacecraft.
In April, Northrop Grumman vibrations twice as intense as expected at the launch. At the end of the test, the technicians counted 20 screws out of 1,000 that are needed to cover a thin layer covering the visor.
These screws, of a width equal to half a dime, are designed for nut. But the end of the screws could potentially scratch or tear the sunshield. Somewhere in the process, the technicians had decided to add a washer to prevent the screws from protruding up to now. They did not realize that this could impede the lock function, and some screws came a short thread.
In another error, the bad solvent was used in the cleaning boosters. And the wrong kind of wiring leads to excessive voltage. These three mistakes – the screws, the solvent, the wiring – brought the project back to a year and a half and about $ 600 million, the panel concluded.
The Webb dates back to 1993, when a group of astronomers proposed to NASA's infrared space telescope with a mirror of four meters (about 13 feet) in diameter, at an initial estimated price $ 500 million. But then, NASA's administrator, Dan Goldin, pushed for something more daring.
"Why do you ask for such a modest thing, why not go after six or seven meters?" Goldin said in a speech to astronomers in San Antonio in 1996.
John Mather, a NASA scientist and champion of the Webb, said the telescope could have been smaller and simpler, but that would have resulted in a less sensitive observatory.
"This is not just another thing a little better than Hubble.It is dramatically different," said Mather.
NASA sits on 6.5 meters at an estimated $ 4 billion. The launch date slipped from 2007 to 2011, and then until 2013.
"At every meeting, the goal posts were moving," said world-wide astronomer Heidi Hammel, who plans to Use the Webb for his research. "You could see that the costs were not managed properly."
The costs of the telescope began to reduce funding for other NASA astronomy projects. An article in the journal Nature baptizes the Webb "the telescope that ate astronomy". The Webb program has cost more than half a billion dollars every year since 2011.
In 2010, an independent journal chaired by John Casani, a veteran project The director of the Jet Propulsion Laboratory said the "lack "effective surveillance" of NASA "resulted in a project that was simply not executable."
The following summer, the Parliamentary Appropriations Committee recommended the complete cancellation of the mission . It was at that time that we had to take a cold air and ask if it was worth going scientifically on the carpet, "said Hammel." And the answer is "yes". It was worth it. "
The Webb had a powerful political backing of then-Sen. Barbara A. Mikulski (D-Md) .The telescope survived its dark period and the launch date was set at 2018, then reset several times for the current goal of 2021.
Congress must now reauthorize the Webb, which is about to break a $ 8 billion cap imposed in 2011 L & # Current estimate of $ 9.7 billion includes future costs of operations and data analysis.Here up there is no sign that lawmakers could try to pull the plug on the telescope.
"It's a mission on the verge of what is possible," said Zurbuchen of NASA
"to be a triumph for NASA and the astronomical community." If that fails, this will be considered a tragedy for science and for the many people who have dedicated a great deal of their lives at this space observatory.
And critics will argue, plausibly, that it was too big a telescope too
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