NASA's Next Space Telescope Is Running Out of Time

The world’s next great space telescope is falling behind.

The James Webb Space Telescope, NASA’s successor to the famed Hubble, is at risk of experiencing significant delays in development, according to a new report from a government agency that audits federal programs.

Webb is an $8.8 billion project two decades in the making. Last September, NASA announced it was delaying the telescope’s launch by at least five months, from October 2018 to between March and June 2019. At the time, NASA officials said the change wasn’t due to any problems with the hardware, but because assembling the telescope’s many complex parts was “taking longer than expected.”

That delay may not be the last, according to the Government Accountability Office. “Based on the amount of work NASA has to complete before JWST is ready to launch, we found that it’s likely the launch date will be delayed again,” the office said in a statement accompanying its 31-page report, released Wednesday.

Thanks to the delay announced in September, the project now has just one-and-a-half months of “schedule reserves,” time allocated to address delays or unexpected problems, the report said. If Webb runs over that time, it comes dangerously close to exceeding the cost cap Congress set for the project in 2011.

This is a disheartening forecast for many parties, including NASA; Northrop Grumman, the telescope’s main contractor; and the European and Canadian space agencies, contributors to the telescope’s design and construction. There’s no question that the Webb will launch. After 20 years of development and construction, most of the money has already been spent and the hardware rigorously tested. But the road to the launchpad may be bumpier than everyone expected.

NASA was already thinking about the Webb telescope when Hubble had barely left the ground in 1990. The space agency’s dream for its next-generation space observatory was a telescope that could see in infrared wavelengths to reveal the faint light from the most distant stars and galaxies.

Webb is both a tremendous feat of human engineering and an incredibly beautiful object. With a 22-foot-tall honeycomb arrangement of 18 mirrors, fashioned out of lightweight beryllium and plated in gold, the Webb looks more like a piece of modern art than a space robot.

Once completed, the telescope will be an amalgamation of several complex pieces of hardware. Most of the assembly for Webb took place at NASA’s facility in Maryland, the Goddard Spaceflight Center, where it underwent a barrage of tests. In January 2016, scientists and engineers dunked the telescope’s sensitive instruments into a cylindrical chamber that simulates the extreme conditions of outer space. By November 2017, the delicate mirrors and instruments were joined together, and mission members put them through the ringer to make sure they could survive the vibrations and sounds of a powerful rocket launch. They bolted the telescope to metal plates and shook it violently, then wheeled it into an acoustic chamber and blasted it with noise through giant, vuvuzela-shaped speakers.

At the end of every test run, scientists and engineers stepped back and reviewed the data to check for any anomalies. They found one in February 2017 during vibrations testing. The GAO report said fixing the problem, which was never described publicly, took more than a month and delayed other tests by several weeks.

Other issues in April took up another month, this time with the spacecraft, which will house the observatory’s computers and solar panels, and the sun shield, the tennis-court-sized layers that will protect the technology from the sun. Both are being constructed in California, where Northrop Grumman is based. The GAO’s description of what happened is pretty excruciating. “A contractor technician applied too much voltage and irreparably damaged the spacecraft’s pressure transducers, components of the propulsion system, which help monitor spacecraft fuel levels,” the report explains. “The transducers had to be replaced and reattached in a complicated welding process.”

In May, Webb was packed into a shipping container and flown on a C-5 military transport plane to NASA’s sprawling facility in Texas, the Johnson Space Center. Engineers dipped the telescope into a massive cryogenic testing chamber that exposed the hardware to the frigid temperatures of space. The telescope survived the test, as well as the devastating wrath of Hurricane Harvey, which flooded the streets of Houston and forced some of Webb’s guardians to hunker down and sleep in offices or conference rooms at Johnson until the storm passed.

Webb will eventually be flown to California, where it will receive its sun shield and spacecraft hardware and undergo still more tests. When its many parts are finally assembled, Webb will be too massive to transport by plane, so it will sail by ship to French Guiana. There, it will take off from a European-operated launch facility, aboard an Ariane 5 rocket built by the European Space Agency. The Ariane fleet recently sparked some readiness concerns of its own when a rocket launched its payload, two communications satellites, into the wrong orbits. NASA has joined the European Space Agency in its investigation of the anomaly. The agencies have a full year to troubleshoot and implement fixes, but there’s no doubt the situation has rattled the nerves of the Webb team.

The GAO report starts out by praising the Webb mission for making “considerable progress” in the last few months in hardware integration, but things go downhill from there.

The GAO places blame on Northrop Grumman for delays. “For several years, the prime contractor has overestimated workforce reductions, and technical challenges have prevented these planned reductions, necessitating the use of cost reserves,” the report said. Northrop Grumman did not respond to a request for comment about this assessment.

GAO says Northrop Grumman ate up three months of reserve time “due to lessons learned from conducting deployment exercises of the spacecraft element and sun shield,” but doesn’t say what those are.

This sounds particularly ominous when you consider just how complicated Webb’s deployment process is going to be. When the telescope launches, Webb will be folded up like a flower before spring. As it travels to its orbit around the sun, Webb will spend about two weeks blooming, unfurling solar arrays, antennas, the sun shield, and other components, all the while making course corrections so it ends up in the right place. The automated process involves about 180 deployments. Very, very little can go wrong. NASA officials have said Webb can only withstand the failure of about six steps in this sequence. If the telescope experiences a glitch that prevents it from opening up completely, it will become just another piece of abandoned space junk. Unlike Hubble, the Webb is not designed to received repair crews, and at nearly 1 million miles from Earth, it’s too far for astronauts to reach with current U.S. spaceflight technology.

Webb risks running out of money, too. In total, the project will cost $8.8 billion: $8 billion for development and construction and $837 million for operations. When Webb was first proposed, estimates suggested the project would require between $1 billion to $3.5 billion. Costs ballooned significantly over the years, prompting Congress to instruct NASA not to go over $8 billion for development and construction. The latest and potential future launch delays put Webb “at risk of breaching” this cap, GAO said. Webb’s expensive price tag has made government officials skittish about the space telescope NASA wants to launch after Webb. The Wide-Field Infrared Survey Telescope (WFIRST), which will study exoplanets and mysterious dark energy, is still in the early stages of development. Last year, NASA headquarters instructed the WFIRST team to reduce the budget by $400 million. Last month, the Trump administration proposed canceling WFIRST, citing budget constraints.

If the GAO report is any indication, there may be more troubling news for Webb to come. An independent review board for the Webb mission will conduct its own audit of the project early this year to determine whether it will make its new 2019 launch target.

In the meantime, the Webb team has been reviewing and selecting research proposals for its first year of operations. The telescope, 100 more times powerful than Hubble, will be able to see deeper into the universe than ever before. Hundreds of astronomers, from many countries, want their time on it. In its first few months, Webb will focus on nearby targets—the planets in our solar system—and distant ones—glittering galaxies way out in the cosmos. It will return stunning images of it all in tremendous clarity and color. Perhaps then, when we lay eyes on these photographs, the long wait will have seemed worth it.

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