CALIFORNIA BUILT
How our camera captured Webb Space Telescope's famed first images
In a triumphant technological tour de force, a Bay Area-built camera the size of a coffee table is sending home snapshots of our infant universe from the James Webb Space Telescope, ushering in a new era of astronomical exploration.
As the world waited in suspense on Tuesday morning, its photos popped into view — luminous 150-million pixel images of a time long before we existed, when stars and galaxies first emerged from the primordial fog almost 14 billion years ago.
On a video screen in a dim room at Lockheed Martin's Advanced Technology Center in Palo Alto, scientists and engineers burst into applause. It was their first glimpse of a portfolio of images that was conceived two decades ago, with no guarantee of success.
“There's a mixture of emotions,” said Lockheed Martin's Malcolm Ferry, program manager of the camera project, who joined the ambitious effort when his son, now a married adult, was just a boy.
“There's joy. Elation. Relief that it's all working, creating pictures are just gorgeous,” said Ferry of Emerald Hills. “And maybe I'm a little sad, knowing that this part of the journey is over.”
One of their photos — a stunning image of a distant star cluster called SMACS 0723, in the Southern Hemisphere constellation of Volans — was selected for President Biden's preview and released around the globe Monday. Other images show the Southern Ring Nebula, the Carina Nebula and “Stephan's Quintet,” a cluster of five galaxies in the constellation Pegasus.
The Near-Infrared Camera, or NIRCam, is traveling a million miles from its birthplace in a leafy Stanford-based research park.
And there's no way to fix it if it breaks; it's too far away.
Four hundred years after Galileo Galilei used a fancy spyglass to gaze at the moon, this camera can detect special wavelengths of light to, in essence, peer back into far ancient time — 100 million years after the Big Bang. Our previous images, taken by the Hubble telescope, date to a time 400 million years after the Big Bang.
The Webb telescope can't show us the moment of our birth, when the universe came out of nothing about 14 billion years ago. For many years after this Big Bang, the cosmos was just
a dense cloud, a dark and messy place.
But it reveals the first remarkable steps of the universe's self-assembly, when it spawned galaxies, stars, planets — and, eventually, a creature with a brain big enough to wonder: “Where did we come from? What did it look like?”
To the team's delight, the camera survived the stress and strain of an explosive launch into space from French Guiana last December.
Now it must work with utmost precision and stability in extreme cold temperatures aboard Webb, the largest and most powerful space telescope ever built.
A second duplicate camera is also on board, as backup.
NIRCam and Webb's other teams were conceived in 2002, when George W. Bush was president, the U.S. had just invaded Afghanistan and iPods were newly released. The Lockheed Martin team partnered with principal investigator Marcia Riki of the University of Arizona for the project.
“It took so long. To see all that come together — and see the results — is very, very inspirational,” said Nelson Pedreiro, vice president of Lockheed Martin's Advanced Technology Center, where the camera was designed and assembled.
Webb's 18-paned mirror collects light from the sky and directs it to four instruments, including NIRCam, the main source of its images. Another instrument studies the composition of space material; a third guides and points the spacecraft.
Webb has a larger mirror than Hubble, so the camera's images are higher resolution. While Hubble's images were a bit fuzzy, Tuesday's photos were breathtakingly clear and detailed.
Webb's mirrors are lined with a microscopic layer of gold that reflects infrared light better than nearly any other metal. They're 98% reflective, so they can capture almost all incoming photons of light.
“It was very challenging, from a technology and engineering perspective,” said Pedreiro, who lives in Menlo Park.
NIRCam can detect infrared light that ranges from 0.6 to five microns — far beyond the part of the spectrum that was visible to the lens of its predecessor, the Hubble telescope. That makes it possible to view much more ancient objects. As the universe expands, wavelengths shift. Because the oldest light is long and red, it cannot be viewed by human eyes and conventional telescopes.
It differs from a conventional camera in other ways, with special coatings, filters and more refined optics, splitting light into two paths to capture different infrared wavelengths.
“If the surfaces are not perfect — and they're never perfect — they ended up distorting the light,” said Pedreiro.
There were several major challenges, said Ferry.
One was finding a way to protect the very fragile glass from shattering during sudden change in temperatures and the spacecraft's violent launch. So the Lockheed Martin team designed a special device to hold the lens, using flexure mounts. They also developed a new bonding technique, gluing the lens to the mount.
Another was building a camera that would still work despite shrinkage in the extreme cold. In space, Webb operates at minus-447 degrees Fahrenheit. So its design had to anticipate a change in shape and size. The scientists worried that such stress would break glass.
“We're human beings who have to put this thing together, at room temperature,” said Ferry. “Once it gets up there, everything moves around. But it still has to be aligned.”
In 2014, the camera was carefully picked up in Palo Alto by FedEx's special “white glove” team, then shipped to Maryland's Goddard Space Flight Center, where it was integrated with the other instruments. From there, it went to Florida's Johnson Space Center for testing, then Northrop Grumman in Redondo Beach to be placed into the spacecraft. Finally, the whole project was flown to South America for launching.
“We built an instrument that nobody had ever built before, with requirements that had never been imposed before,” said Ferry.
“It was the first time,” he said, “for it all.”