How the James Webb Space Telescope transformed astronomy this year
One year ago, the James Webb Space Telescope began its journey through space.
“JWST was launched on Christmas Day and then it was a gift that took six months to open,” said Jane Rigby, a NASA astronomer and project operations scientist.
After an initial calibration period, the telescope began collecting data. And the first results surprised astronomers.
“I downloaded the data and I was like sitting in my pajamas…you know, it’s a pandemic, we’re all working from home,” Rigby said. “I pulled that data back and started flipping through it, pouring it out. And it was so beautiful.”
The telescope is only five months into its science mission and is already transforming astronomy. The telescope’s instruments have allowed it to capture previously unobservable planets, stars, and galaxies near and far.
NPR spoke with three astronomers in different disciplines of astronomy about how JWST is advancing research in their area of expertise. Everyone agrees that JWST is a game changer and that there is still much more groundbreaking research to come.
“The ring systems are obvious and magnificent”
Heidi Hammel is a planetary astronomer and interdisciplinary scientist with the JWST Project. She joined the team in 2002 because she wanted to study the planet Neptune.
In September, JWST focused its mirrors on the ice giant.
“When I first saw the image on my computer screen, I was very excited,” Hammel said. “First I started crying, and then I started screaming and calling all my relatives to come and see this photo.”
Before the JWST, Hammel said, astronomers had never clearly observed Neptune’s ring system. The Voyager spacecraft flew by Neptune in 1989, but was only able to capture the brightest parts of the planet’s rings.
JWST’s instruments detected the rings with unmatched clarity.
“Boom! The ring systems are so eye-popping and beautiful,” Hammel said.
“How to get out of a virtual reality into the real world”
Outside our own solar system, JWST has also helped astronomers observe the oldest and most distant known galaxies.
“I’ve been looking at simulated data, trying to mimic what JWST would see, for many years. So when I first saw the data, it was like stepping out of virtual reality into the real world,” said Brant Robertson, professor of astronomy and astrophysics. at the University of California, Santa Cruz.
Robertson is on a team of researchers that discovered the oldest galaxies ever observed. JWST’s instruments enabled his team to identify galaxies up to 13.4 billion years old, galaxies that would have formed less than 400 million years after the Big Bang, a small fraction of the lifetime of the universe.
“By finding these very early galaxies, we can learn something about our history, about the history of the universe in general, but also about our home specifically,” Robertson said.
Robertson said that while older telescopes like Hubble gave astronomers a glimpse of what was out there, JWST has broadened the scope of what kind of science is possible.
“Virtually everything we’re doing wasn’t possible before this telescope”
Jane Rigby, JWST operations project scientist, is also using the telescope to study distant galaxies.
A natural phenomenon called gravitational lensing magnifies the light from the galaxies Rigby is observing; combining it with JWST, he has been able to cut through cosmic dust to study how stars form in these galaxies.
“Most everything we’re doing wasn’t possible before this telescope,” Rigby said.
Hubble’s instruments would not have been able to see through the dust that obscures these galaxies, Rigby said. In addition, JWST’s instruments allow you to study the material composition of these galaxies through spectroscopy, a technique that astronomers often use to identify the chemical composition of objects in space.
“We are studying where stars are forming in these lensed galaxies in ways that are ridiculously impossible with any other telescope,” Rigby said.
JWST has already proven to be an incredible tool for astronomers, but its biggest discoveries are yet to come, Rigby said.
“We’re starting to get this deluge of papers announcing discoveries,” he said. JWST is being used to study planets in our own solar system, atmospheres of planets in other solar systems, how stars die, how galaxies evolve and much more, Rigby said.
And even though JWST is significantly more powerful than previous telescopes, Rigby says astronomers can still use Hubble to supplement JWST observations.
“In many ways, JWST was created to do the things that Hubble can’t, so they work very well together,” Rigby said. “The pitcher and catcher on your baseball team do different things.”
The telescope has enough fuel on board to last more than 20 years in space, Rigby said, so it’s possible it could survive its minimum planned mission of five years.
“I think next year will be even more exciting than this year,” Rigby said.
After all, it will take time to analyze the data that the James Webb Space Telescope collects and see how much it can change our understanding of the many mysteries of the universe.
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