UMass Amherst astronomers were among a team of scientists that processed a new image from the James Webb Space Telescope that reveals never-before-seen details of a region in space dubbed Pandora’s Cluster, NASA said last week.
“These galaxies are some of the very first galaxies in the universe,” Katherine Whitaker, an assistant professor of astronomy at UMass Amherst, said in a phone interview. “Webb is like a time machine.”
Beginning in November, Whitaker and John Weaver, a postdoctoral research associate at UMass, helped process, analyze, and correct the raw output from the Webb Telescope, they said. The final image was released Wednesday.
“We all just stared at that image when it first came out,” Weaver said. “Everyone was just really, really excited. The image is just breathtaking.”
Most of the objects in the image — the white, hazy dots — are each massive, individual galaxies in the deepest parts of Pandora’s Cluster, Whitaker said. Because their light waves take so long to reach Earth, the image looks back in time, she said. The red, tiny galaxies in the image are still in their infancy, tracing back to the origins of the universe about 13.8 billion years ago, according to a statement from NASA.
The Webb Space Telescope, which first launched in December 2021, orbits the sun over a million miles away from Earth. Unlike other telescopes, Webb uses an infrared camera to perceive longer wavelengths of light, which the human eye can’t detect, Whitaker said.
“We actually can’t see the first galaxies in Pandora’s Cluster with traditional optical telescopes,” Whitaker said. “It’s impossible.”
As the universe expands, and the light emitted from distant galaxies travels a greater distance, the wavelengths lengthen, Whitaker said. The Webb Telescope can perceive the longer wavelengths, allowing astronomers to see deeper into space than ever thought possible, she said.
“It’s revolutionary. We’re tracing cosmic history,” Weaver said.
There’s been previous research into Pandora’s Cluster, but past images from Webb’s predecessor, the Hubble Space Telescope, did not detect nearly as many galaxies, Weaver said. The new images, which were taken with exposures lasting four to six hours, were able to detect almost 50,000 sources of unseen, near-infrared light, NASA said.
“We’re analyzing all this data and finding the really cool and interesting objects, to then follow up in July of this year to get deep spectroscopy,” Whitaker said.
As part of the analysis, Whitaker and Weaver’s team, UNCOVER — short for Ultradeep NIRCam and NIRSpec ObserVations before the Epoch of Reionization — individually cataloged each of the galaxies, identifying and studying their properties, NASA said. The team took four Webb snapshots and stitched them together to form the one panoramic image, the statement said.
“You have to figure out how much light these galaxies are giving off in different wavelengths, calibrations that are inherent to that process,” Whitaker said. “So we’ve been doing lots of checks and balances to make sure that everything makes sense and that we trust it.”
Now that the output from the telescope has been analyzed, scientists can further probe into the catalogs and the “different epochs of our universe,” Whitaker said.
“As a team, we’re now at that stage where we’re starting a lot of science projects that leverage this beautiful data set,” she said.
The image hints to answers to deeper existential questions, including the origins of galaxies and the universe itself.
“That’s where the fun begins,” Whitaker said.
Kate Armanini can be reached at firstname.lastname@example.org. Follow her on Twitter @KateArmanini.