The Webb telescope is just getting started

The Webb telescope is just getting started

The Webb telescope is just getting started

BALTIMORE — So far it’s a sight to behold: the black expanse of space teeming with enigmatic, unfathomably distant spots of light. Spooky portraits of Neptune, Jupiter and other neighbors we thought we already knew. Nebulae and galaxies made visible through the penetrating infrared eyes of the James Webb Space Telescope.

The telescope, named after James Webb, the NASA administrator leading up to the Apollo moon landings, is a joint project between NASA, the European Space Agency and the Canadian Space Agency. It launched a year ago at Christmas – after two decades of trouble and $10 billion – up a mission to observe the universe in wavelengths that no human eye can see. With a 21-foot-wide primary mirror, the Webb is seven times more powerful than its predecessor, the Hubble Space Telescope. Depending on how you do the accounting, an hour of observing time on the telescope could cost NASA $19,000 or more.

But neither NASA nor the astronomers paid all that money and political capital just for pretty pictures — not that anyone’s complaining.

“The first images were just the beginning,” said Nancy Levenson, interim director of the Space Telescope Science Institute, which runs both Webb and Hubble. “It takes more to turn them into real science.”

For three days in December, some 200 astronomers filled an auditorium at the institute to hear and discuss the telescope’s initial results. About 300 more were viewed online, according to organizers. The event served as a belated celebration of the successful launch and inauguration of the Webb and a preview of its bright future.

One by one, astronomers marched to the podium and speaking at lightning speed to respect the 12-minute limit, they flashed through a cosmos of discoveries. Galaxies that, even in their relative youth, had already spawned supermassive black holes. Atmospheric studies of some of the seven rocky exoplanets orbiting Trappist 1, a red dwarf star that could host habitable planets. (Data suggests that at least two of the exoplanets lack the bulky primordial hydrogen atmosphere that would suffocate life as we know it, but they may have skimpy atmospheres of denser molecules like water or carbon dioxide.)

“We’re in business,” declared Bjorn Benneke of the University of Montreal, presenting data from one of the exoplanets.

Rice University’s Megan Reiter took her colleagues on a “deep dive” through the Cosmic Cliffs, a cloudy hotbed of star formation in the Carina constellation that was a favorite early piece of sky candy. She follows how beams from new stars, shock waves and ionizing radiation from more massive nearby stars born boiling hot continuously reshape cosmic geography and trigger the formation of new stars.

“This could be a template for what our own sun went through when it formed,” said Dr. Rider in an interview.

Between presentations, on the sidelines and in the hallways, senior astronomers who were present in 1989 when the idea of ​​the Webb telescope was first discussed congratulated each other and exchanged wartime stories about the telescope’s development. They gasped audibly as the youngsters showed data that blew past their own achievements with the Hubble.

Jane Rigby, the operations project scientist for the telescope, recalled her emotional tumult a year ago when the telescope finally approached its launch. The instrument was designed to unfold in space – a complicated process with 344 possible “single-point failures” – and Dr. Rigby could only count them, over and over.

“I was in denial,” she said in Baltimore. But the launch and implementation went smoothly. Now she said, “I’m living the dream.”

Garth Illingworth, an astronomer at the University of California, Santa Cruz, who chaired a major meeting at the Space Telescope Science Institute in 1989 that eventually led to the Webb, said simply, “I’m just blown away.”

At a reception following the first day of the meeting, John Mather of NASA’s Goddard Space Flight Center and Webb’s senior project scientist from the start raised a glass to the 20,000 people who built the telescope, the 600 astronomers who tested it in space and the new generation of scientists who would use it.

“Some of you weren’t even born when we started planning for it,” he said. “Just try!”

So far, the telescope, packed with cameras, spectroscopes and other instruments, has exceeded expectations. (Its resolving power is twice as good as advertised.) Thanks to the telescope’s flawless launch, Dr. Rigby, it had enough maneuvering fuel to keep it running for 26 years or more.

“These are lucky numbers,” she said, as she and her colleagues dug up their instruments’ performance stats. Dr. Rigby cautioned that the telescope’s instruments are still being calibrated, so the numbers could still change. Prepare to recalculate your results at the touch of a button, she told a group of astronomers in the lobby: “Otherwise you’ll hate your life.”

Perhaps the Webb telescope’s biggest surprise yet concerns events in the early millennia of the universe. It appears galaxies formed, generated and nurtured stars faster than battle-tested cosmological models estimate.

“How Did Galaxies Get So Old So Fast?” asked Adam Riess, a Nobel laureate in physics and cosmologist from Johns Hopkins University who stopped by for the day.

Exploring that province – “cosmic spring,” as one astronomer called it – is the goal of several international collaborations with snappy acronyms such as JADES (JWST Advanced Deep Extragalactic Survey), CEERS (Cosmic Evolution Early Release Science), GLASS (Grism Lens -Amplified Survey From Space) and PEARLS (Prime Extragalactic Areas for Reionization and Lensing Science).

Webb’s infrared vision is fundamental to these efforts. As the universe expands, galaxies and other distant celestial objects are speeding away from Earth so fast that their light has stretched and shifted to invisible, infrared wavelengths. Beyond a certain point, the most distant galaxies recede so quickly, and their light is so stretched in wavelength, that they are invisible even to the Hubble telescope.

The Webb telescope is designed to uncover and explore these regions, which represent the universe only a billion years old, when the first galaxies began to bloom with stars.

“It takes time for matter to cool and become dense enough for stars to ignite,” noted Emma Curtis-Lake of the University of Hertfordshire and member of the JADES team. The rate of star formation peaked when the universe was four billion years old, she added, and has been declining ever since. The cosmos is now 13.8 billion years old.

Astronomers measure cosmic distances with a parameter called redshift, which indicates how much the light from a distant object has been stretched. Just a few months ago, a redshift of 8, which corresponds to a time when the universe was about 646 million years old, was considered a high redshift. Thanks to dr. Curtis-Lake and colleagues, the record redshift is now 13.2, which corresponds to when the universe was only 325 million years old.

Dr. Curtis-Lake and her team had aimed the telescope at a patch of sky called GOODS South, looking for galaxies that Hubble had failed to detect. Sure, there were four of them, shadows in the heat fog of creation. Later measurements confirmed that they were indeed far back in time.

“We didn’t want to say we believed it — publicly,” says Brant Robertson, a JADES member at the University of California, Santa Cruz.

The record is not expected to stand for long. The CEERS collaboration has reported a galaxy candidate that could have a redshift of 16from the time when the universe was only 250 million years old.

Experts are already debating whether these overzealous galaxies reveal something fundamental, and overlooked, in current theories of the early universe. Perhaps some field or effect at the time increased gravity and accelerated the growth of galaxies and black holes. Or perhaps the discrepancies simply reflect scientific uncertainties about the messy details — the “gas physics” — of star formation.

Over the past 20 years, astronomers have developed a solid “standard model” of a universe composed of dark energy, dark matter, and a little bit of atomic matter. It’s too early to break that model, Dr. Curtis-Lake said in an interview; Webb may have three decades of observing ahead of him. “We’re in the early stages,” she said.

The closing talk was for Dr. Mather. He outlined the telescope’s history and shouted out to Barbara Mikulski, the former Senator from Maryland, who supported the project in 2011 when it was under threat of cancellation. He also previewed NASA’s next big act: a 12-meter space telescope called the Habitable Worlds Observatory that would seek out and study planets.

“Everything we’ve done has paid off,” he said. “So we’re here: this is a celebratory party, getting a first look at what’s out here. It’s not the last thing we’re going to do.”



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