NASA's next great space telescope is stuck on Earth after screwy errors

NASA's James Webb Space Telescope was supposed to be a million miles from Earth by now, peering deep into the universe and back in time to when stars were first assembling into galaxies. But its launch is still years and billions of dollars away, and mission success depends on many delicate things going exactly right. The telescope unfortunately has some screws loose.

کد خبر: ۸۱۹۶۴۱

تاریخ: ۰۳ مرداد ۱۳۹۷ - ۰۹:۰۱

And washers. And nuts.

Technicians discovered that rogue screws fell off during a test this spring. This was among several forehead-smacking errors and design flaws that have put off until March 2021 the launch of the telescope,which has so far cost taxpayers about $7.4 billion and now has an estimated price tag of $9.7 billion.

The travails of the Webb will be the focus of two days of testimony, starting Wednesday, before the House Science Committee. Among those appearing and certain to face difficult questions will be NASA Administrator Jim Bridenstine and Wes Bush, the CEO of the primary contractor, Northrop Grumman.

The Webb's problems have rattled many powerful constituencies. NASA is embarrassed and dismayed by the human errors that have snarled its biggest robotic science project, which was identified by the astronomy community back in 2000 as its top priority.

The U.S. aerospace industry, which is dealing with a wave of retirements, needs to prove to national leaders that it remains as competent as when it put people on the moon. The same companies that build civilian space telescopes also build spy satellites. Earlier this year, a classified Defense Department satellite code-named Zuma was lost after it failed to separate from a rocketbooster. That satellite was built by Northrop Grumman.

An independent review board report this summer declared that the Webb is potentially vulnerable to 344 different "single-point-failures" - an extraordinary number for any mission. That meansif a single metal strut fails, or a single cable gets snagged, "we have a ten-billion-dollar paperweight sitting out there," said astrophysicist Grant Tremblay of the Harvard-Smithsonian Center for Astrophysics.

Unlike the Hubble Space Telescope, the Webb cannot be repaired in space. It will be placed more than four times farther from Earth than the moon.

Many young scientists have been counting on the Webb for research essential to advancing their careers. But they also understand that it has to be done right.

"We know once this thing goes into space, we can't fix it," said Victoria Scowcroft, an astrophysicist at the University of Bath in Britain. "We would much rather wait for a telescope in space that works than not have one."

NASA is reviewing its science programs, Thomas Zurbuchen, NASA's top science official, told The Washington Post.

"How prevalent are human errors?" Zurbuchen said. "How many more mistakes are there?"

NASA officials have increased oversight of Northrop Grumman. About a dozen NASA employees are embedded full-time at the contractor's Redondo Beach, California, facility and more NASA experts rotate through regularly.

Thomas Young, a former NASA official who chaired the review board, is adamant that the project should go forward, but with greater care: "There's got to be an all-out effort to try to find any additional embedded problems."