BALTIMORE — The banner hanging on the front of the Steven Muller building on the Johns Hopkins University campus might have to come down soon.
“Go Webb Go!” it beams. “The hidden universe awaits.”
As of Tuesday, the hidden universe has arrived — by way of Baltimore’s own Space Telescope Science Institute.
The institute at Hopkins, which houses the mission control for the revolutionary James Webb Space Telescope, hosted its own unveiling of the telescope’s first set of awing images — full-color images of deep space as it’s never been seen before.
It was one of hundreds of viewing events across the country and the world on Tuesday, following a sneak preview of an image Monday evening from President Joe Biden. But it was the only event held at the very place where Webb’s first dispatches from the cosmos met human eyes.
Some in attendance had already seen the stunning nebulae, the entrancing five-galaxy cluster with a background of many more. But astounded whispers and applause still filled the room when each photograph hit the projector screen, a testament to decades of collaboration, followed by several nerve-wracking months of calibration with Webb roughly a million miles away from Earth.
“This is why we postponed vacations, worked weekends and night shifts and had sleepless nights even when we weren’t working,” said Kenneth Sembach, director of the Space Telescope Science Institute. “Here we are today, and we can say we did it. And it was worth it.”
He paused. “Right?”
Laughter and applause filled the auditorium.
With Webb, the most powerful space telescope launched into outer space, practically every observation peers deeper than ever before. Where previous telescopes, like Hubble, only saw black depths, Webb captures a backdrop of even more distant galaxies, providing scientists with new visions of the early universe.
“We have a joke that these background galaxies are contamination now,” Sembach said. “Because before, we weren’t seeing them, and now they’re in every image that you take, and you have to account for those in some way.”
At Tuesday’s event in Baltimore, the first order of business was a status report from Webb’s commissioning scientist Scott Friedman, delivered like a recitation of a straight-A student’s report card.
The images are sharper than expected, the instruments more sensitive, the pointing performance more exact.
There were, of course, some unexpected blips — like the discovery of scattered light impacting the telescope’s coronagraph instrument. But the impact is likely to be negligible, Friedman said.
Then came an astronomic art lesson from Joe Depasquale, senior science visuals developer at the institute’s Office of Public Outreach.
A deep-black image with a handful of white pinpoints of light flicked onto the screen.
“Believe it or not, I’ve actually just revealed to you the Carina nebula image,” he said.
That image, a thick cloud of deep orange filled with bursts of starlight, had to be teased from the sea of darkness, Depasquale explained.
To get there, artists at the institute in Baltimore had to assign a color palette to wavelengths of light that human eyes cannot see. Webb uses infrared instruments to capture objects so distant in space that their light has been redshifted by the ever-expanding universe.
The initial formula is simple, Depasquale says; the shortest wavelengths captured by Webb are assigned to blue and the longest to red, with the middle of the spectrum assigned to greens.
From there, Depasquale’s team tinkers with the colors and contrast to ensure the images are their brightest selves, along the way establishing a signature color palette for Webb that will unite all of its images to come.
“This is really the universe’s preference of color, not my preference,” Depasquale said. “I just do the work. I bring it out.”
Next, without much fanfare, came humanity’s deepest-ever look into outer space, captured by Webb and revealed for the first time by Biden. The image, crammed with swirling orbs, captures a galaxy cluster that acts as a magnifying glass, depicting other galaxies even farther away in the background.
“We really just scratched the surface,” said scientist Alaina Henry. “The NIRCam image was only 12 hours when you put all the bands together. The Hubble Deep Field, for example, was hundreds of hundreds of hours. And so when we eventually get it together and do this with Webb, it’s just going to be — I don’t know what to expect.”
That’s not to mention Webb’s unique power to obtain details about individual distant planets, which could hold clues about life elsewhere in the universe.
Néstor Espinoza, an assistant astronomer at the Baltimore institute explained the once-incredibly difficult process of observing such faraway worlds. Scientists observe the planets when they are in transit, meaning they are passing in front of their star, relative to Earth. At that time, some of the starlight is absorbed by the planet’s atmosphere. Using observatories like Webb, scientists can measure how much and use that information to determine what elements make up an atmosphere.
But the process is complicated. Scientists must cancel out potential distractions. For instance, when they observe from ground-based telescopes, they must correct for the impact of Earth’s atmosphere, Espinoza said. Even with modern space telescopes, sizable corrections needed to be made. That is, before Webb.
The data for a giant exoplanet, called Wasp-96 b, flashed onto the screen. To a room full of astronomers, the difference in the data was evident almost immediately.
“This is absolutely marvelous,” Espinoza said. “You don’t see —”
Before he could finish, knowing chuckles filled the room then a sea of applause.
And for Carina, Amaya Moro-Martín unveiled the breathtaking image, complete with an unforeseen discovery.
”As always, there is room for the unexpected. We have no idea what this is,” she said, highlighting an arc jutting out from the dusty could in the middle of the image. It was a fitting end to the event, with the promise of even more unexpected discoveries to come. Webb is already at work on its first round of discoveries, proposed by teams of astronomers and carefully selected by their peers.
After Tuesday’s event came a Champagne toast led by former Sen. Barbara Mikulski outside the institute, where scientists embraced and held glasses aloft to celebrate the beginning of Webb’s scientific journey.
Inside, visitors signed a matte backdrop that will be featured behind a collage of Webb’s first images in the institute. And beside them, onlookers peered at a tablet, entranced by Webb’s deep-field image, and were already busy discussing what it meant for Webb’s future.
It was time for celebration. There were James Webb cookies, plus a three-tiered cake, with a model of the observatory and its 18 hexagonal mirror segments on top.
“I think we should all feel extremely fortunate to be here at this moment in time, when all of this is happening in the building where we control this technological marvel from a million miles away,” Espinoza said.
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