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University of Arizona Astronomer Designed NASA’s New Camera

A team led by university astronomer and regents’ professor Marcia Rieke completed the main camera for NASA’s new $10 billion space telescope, the successor to the 31-year-old Hubble, in 2013. It’s set to launch Dec. 25.

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(TNS) — As it turns out, designing the main camera for NASA’s new $10 billion space telescope is a little like that Tom Petty song. The waiting is the hardest part.

University of Arizona astronomer and regents’ professor Marcia Rieke first began working on the James Webb Space Telescope in 1998, when the project was in its infancy.

Since 2002, she has led the development team for the Near InfraRed Camera — NIRCam for short — which will allow Webb to peer into the deepest reaches of the universe in search of light made by galaxies more than 13.5 billion years ago.

Rieke and company handed over the finished camera to NASA in 2013. They’ve been waiting for it to be sent into space ever since.

“We knew we would deliver well before the project launched, but there were a few extra launch delays that none of us had counted on,” Rieke said recently from her office at UA’s Steward Observatory. “You just have to be patient.”

Her long wait may finally end on Christmas morning.

An Ariane 5 rocket carrying the Webb telescope had been scheduled to blast off from a South American spaceport on Dec. 24. But NASA announced Tuesday that another last-minute delay, this time due to high winds, has bumped the launch back to 5:20 a.m. Tucson time Dec. 25 at the earliest.

Rieke said she feels “enormous relief that we’re finally getting there,” but she isn’t exactly holding her breath.

About a month ago, a digital display was installed in the lobby of Steward Observatory so people could follow along with the countdown to liftoff. The clock had been reset twice before the new delay announced Tuesday.

“Bah humbug!” Rieke said with a grin.

CRAFTED ON CAMPUS


The successor to the 31-year-old Hubble Space Telescope has a much bigger primary mirror — 6.5 meters (21.3 feet) in diameter, versus 2.4 meters (7.9 feet) for Hubble.

It is the largest telescope mirror ever flown into space, so it has to be folded up to fit inside the launch vehicle.

Then there is NIRCam, a $460 million package featuring two identical imaging systems that can scan different areas of space at the same time.

The light sensors at the heart of the camera were designed and largely fabricated, assembled and tested on the UA campus. They are made from titanium, molybdenum, silicone and a thin layer of the chemical compound mercury cadmium telluride.

The Astronomy Department has a machine shop downstairs that’s certified by NASA to work with exotic metals and a clean room with a special vacuum chamber where parts can be tested in the simulated cold of space.

When the development process required work by one of the UA’s design partners in California, the sensors would be packed into special shipping containers and sent via “FedEx white glove service,” Rieke said.

Occasionally, she would book a Southwest Airlines flight so she could hand deliver the sensors — each weighing between 5 and 8 pounds — to Lockheed Martin’s Advanced Technology Center in Palo Alto or Teledyne Imaging in Camarillo.

“It was always a little bit of an exercise going through security, because we didn’t want them X-rayed,” she said. “I got to know some of the TSA people.”

All told, Rieke estimates about 50 people at the UA had a hand in the development of NIRCam.

Today, she said, the team includes about 20 professional scientists and “a fair number” of students and postdoctoral researchers — all of them eager to start using the roughly 900 hours of observing time they are guaranteed from Webb through 2025.

Most of the team is still in Tucson, though a few moved on to other universities while they waited for Webb to launch.

“When people get faculty offers, they go,” Rieke explained. “But they’re still members of the team, and we’ve gotten very good at Zooming.”

DESIGNER PAIR


Webb also carries a camera and spectrograph designed by Rieke’s husband, fellow UA astronomy professor George Rieke.

The Mid-Infrared Instrument, or MIRI, is designed to complement discoveries made by NIRCam and study the formation of stars and galaxies and the atmospheres of planets beyond our solar system, among other things.

George Rieke and Gillian Wright from the Royal Observatory in Scotland are the science leads for that instrument.

The entire space telescope is a joint project of NASA, the European Space Agency and the Canadian Space Agency.

“The original rationale for the whole project was to discover the light from the first galaxies to form after the Big Bang,” Marcia Rieke said. “If you had told me when I was a graduate student that I would be studying galaxies that are so far away that we’re seeing them only about a hundred million years after the Big Bang, I would say, ‘I’m not going to live that long.’”

But the new space telescope is anything but a one-trick pony.

“It’s going to get used for lots of things,” she said. “Webb is designed to be quite general purpose, which it better be if it costs $10 billion.”

Rieke has been searching the universe for the most distant galaxies since the early 1980s, back when she had to manually scan the sky to find things without the aid of today’s advanced sensors.

“That was really hard work, and the galaxies that we studied then are ones that we will view as weeds in the (Webb) pictures,” she said with a laugh. “They are too close to be interesting now.”

Rieke grew up reading science fiction in Michigan and majored in physics at MIT, before coming to Tucson to use a telescope on Mount Lemmon for her graduate thesis.

That’s where she met George, who was the keeper of that telescope.

He hired her as a postdoctoral researcher in 1976 and they married in 1982. The UA has been home to infrared astronomy’s biggest power couple ever since.

FLIGHT DELAYS


Back when NASA was soliciting design proposals for NIRCam in 2001, the Webb mission had a preliminary launch date of 2009, though “we all knew that was a joke, because it didn’t seem feasible to build everything that quickly,” Rieke said.

Since then, the project has been slowed by cost overruns, design changes, manufacturing flaws and a few mishaps during assembly.

The first “believable” launch date to come and go was in 2014, she said. “And then that became something like 2016, and that became 2018, and that became 2020 and that became 2021.”

Rieke previously worked on NASA’s Hubble and Spitzer telescopes, so she was used to the occasional setbacks that come with space flight. Other members of the team were not.

“The last two-year launch delay was really a psychological blow to the younger people on the project,” the 70-year-old said. “In around 2014, I started hiring postdocs to work on the data that we’re going to get (from Webb). Most of those people are still here. For them, a two-year launch delay is like half of their professional careers so far.”

Luckily, they’ve had plenty of work to do while they waited.

NIRCam has undergone a barrage of preflight tests over the past eight years to make sure it will survive the shaking during blastoff and the unforgiving conditions in space.

In 2017, Rieke and company hooked their instrument up to the rest of the telescope and tested it at Johnson Space Flight Center in Houston as Hurricane Harvey raged outside.

More recently, telescope team members have been rehearsing what they will need to do during the six-month commissioning stage that will follow Webb’s launch and deployment.

“We’ve also been preparing for our own science program. So we’ve actually ended up being quite busy in spite of the delays,” Rieke said.

Whenever the launch finally happens, students and faculty from the Department of Astronomy are slated to gather in the main lecture hall at Steward to watch NASA’s live stream of the big event.

For Rieke, it will be a moment of excitement and resignation.

“A rocket launch is always scary, because it’s a controlled explosion, but there’s nothing I can do about it. I just have to hope that everyone’s done everything right,” she said. “If it blows up, we’ll all go home crying.”

VERY COOL CAMERA


The waiting won’t end at liftoff, of course.

Once in space, it will take Webb about a month to reach its final destination roughly 1 million miles from Earth, where it will enter a parallel orbit around the sun.

Assuming it unfurls as designed, a heat shield made from five layers of delicate film, each as thin as a human hair, will protect the spacecraft and allow the instruments inside to cool down to about minus 370 degrees Fahrenheit, the optimal temperature for observing in infrared.

Rieke said they won’t even be able to activate NIRCam until it’s nearly as cold as the vacuum of space, a process that’s expected to take about 33 days. It will take several days more after that before the instrument can begin collecting test images.

“We’ll get reports on how all the different unfoldings and so on are going,” she said, “but it won’t be until roughly the third week in January before we really spring into action.”

Rieke said switching NIRCam on for the first time will be the scariest moment for her.

By then, Webb will be parked in space roughly three times farther away than the moon is from the Earth, well beyond the reach of any potential repair mission from home. If anything goes wrong out there, it is very likely to stay that way.

That’s the reason for all the preflight testing, the redundancies, the checks on top of checks and, yes, even the delays. “You can’t go fix it,” Rieke said, “so you’ve got to be sure everything’s right.”

She won’t know that for sure until NIRCam is up and running sometime next year. For now, all she can do is wait.

“I probably will withhold the celebrations until we get some light through (the telescope). Once we start getting some star images, I’ll feel much better,” Rieke said. “Then we’ll uncork the champagne bottles.”

©2021 The Arizona Daily Star (Tucson, Ariz.). Distributed by Tribune Content Agency, LLC.