In this 2017 photo, technicians lift the mirror of the James Webb Space Telescope at the Goddard Space Flight Center in Greenbelt, Md. The telescope is now in California at a Northrop Grumman facility. (Laura Betz/NASA/AP)

NASA's troubled James Webb Space Telescope continues to enjoy congressional support, but lawmakers Thursday expressed dismay with the performance of Northrop Grumman, the huge aerospace contractor that has made a series of errors delaying the telescope's launch until 2021 at the earliest. Wes Bush, the company's chief executive, found himself on the defensive as he testified before the House Science Committee. He refused repeatedly to specify how much profit his company made last year.

The Webb telescope was conceived in 1996 as the successor to the Hubble Space Telescope, and NASA had originally hoped to launch it in 2007.

It is an infrared telescope with a 6.5-meter-wide segmented mirror, and it has to be kept cold to gather light emitted in the early universe when stars were just starting to form galaxies. This requires a tennis-court-sized, five-layer sun shield that has to unfold in space.

In a shake test in April, screws came loose from the sun shield, just the latest in a series of technical glitches and human errors at Northrop Grumman. An independent review board this summer urged NASA and Congress to keep the program going but said there were 344 potential “single-point failures” that could doom the telescope with a single mistake, and it urged greater care in rooting out technical problems. The latest cost estimate of the project is $9.7 billion, most of that already spent.

Bush admitted that mistakes at Northrop Grumman had been a factor in the delays. He pledged that the company would put all of its past profits and potential future profits — known as “award fees” — into a common pot to be awarded only if the telescope is successful.

But he pushed back when House Science Committee Chairman Lamar Smith (R-Tex.) asked him whether the company would consider paying for the latest $800 million cost overrun out of its own pocket. Bush said that would transform the company's cost-plus contract with NASA into a fixed-price contract, and would “significantly impair” the relationship between the company and NASA.

Rep. Dana Rohrabacher (R-Calif.) scoffed at comments made by Bush and other lawmakers about how the Webb will inspire young people.

“I'm sorry that I cannot join you in this uplifting testimony that you've given today. Mr. Bush, I don’t think we should look to our young people and give them an example of being, you know, eight times over budget and twice as long,” he said.

He added, “You can say, 'Is the Jim Webb telescope going to be worth all that money?' That's not what the question is. The question is, 'Is it worth all those other projects that we have been unable to fund in this committee because you have failed your job?' ”

He asked Bush how much profit Northrop Grumman made last year. Bush replied that that's in government filings.

“Is it hundreds of millions or billions?” the congressman asked.

“It's a very large number,” Bush said.

The tension in the room peaked at the end of Bush's testimony, when Smith pressed Bush on whether anyone had been fired for the errors with the Webb project and then tried anew to get Bush to discuss company profits.

Smith: “You do not know as CEO whether any employees lost their job because of the human error?”

Bush: “With respect to the mistakes we’re talking about here today, I do not recall any losing their jobs.”

Smith: “What was Northrop’s profit last year in 2017 just to the nearest tenth of a billion?”

Bush: “We can get you that for the record.”

Smith: “I’m sorry?”

Bush: “We can provide that for you for the record.”

Smith: “Why won’t you tell us today what it is?”

Bush: “I don’t have it in front of me.”

Smith: “How could a CEO not know what the profit of his company was last year?”

Bush: “We will provide that to you for the record.”

The chairman gave up.

The company's financial report for 2017 states that it had pretax earnings of slightly more than $3 billion.

NASA Administrator Jim Bridenstine had testified before the same committee on Wednesday and found himself in friendly territory. He served on the science committee as a Republican representative from Oklahoma until earlier this year, when he was confirmed as President Trump's pick to run the space agency.

Bridenstine acknowledged that the Webb delays will force NASA to “cannibalize” funding meant for other missions. But he extolled the scientific virtues of Webb and said, “We're on the 5-yard line, and we're trying to punch it into the end zone.”

Although he faced some scolding comments, his former colleagues were generally gentle. The most pointed remarks came from Rohrabacher, who began by saying: “This, of course, is very disturbing. This is about the biggest screw job I’ve ever seen, and the taxpayers are getting screwed here.”

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