How the James Webb Space Telescope broke the universe

The James Webb Space Telescope is 1 of MIT Technology Review’s 10 Breakthrough Technologies of 2023. Explore the remainder of the database here.

Natalie Batalha was itching for information from the James Webb Space Telescope. It was a fewer months aft the scope had reached its last orbit, and her radical astatine the University of California, Santa Cruz, had been granted clip to observe a fistful of exoplanets—planets that orbit astir stars different than our sun.

Among the targets was WASP-39b, a scorching satellite that orbits a prima immoderate 700 light-years from Earth. The satellite was discovered years ago. But successful mid-July, erstwhile Batalha and her squad got their hands connected the archetypal JWST observations of the distant world, they saw a wide signature of a state that is communal connected Earth but had ne'er been spotted earlier successful the ambiance of an exoplanet: c dioxide. On Earth, c dioxide is simply a cardinal indicator of works and carnal life. WASP-39b, which takes conscionable 4 Earth days to orbit its star, is excessively blistery to beryllium considered habitable. But the find could good herald much breathtaking detections—from much temperate worlds—in the future. And it came conscionable a fewer days into the beingness of JWST. “That was a precise breathtaking moment,” says Batalha, whose radical had gathered to glimpse the information for the archetypal time. “The infinitesimal we looked, the c dioxide diagnostic was conscionable beautifully drawn out.”

This was nary accident. JWST, a NASA-led collaboration betwixt the US, Canada, and Europe, is the astir almighty abstraction scope successful past and tin presumption objects 100 times fainter than what the Hubble Space Telescope tin see. Almost instantly aft it started afloat operations successful July of 2022, unthinkable vistas from crossed the beingness poured down, from images of remote galaxies astatine the dawn of time to amazing landscapes of nebulae, the dust-filled birthplaces of stars. “It’s conscionable arsenic almighty arsenic we had hoped, if not much so,” says Gabriel Brammer, an astronomer astatine the University of Copenhagen successful Denmark.

But the velocity astatine which JWST has made discoveries is owed to much than its intrinsic capabilities. Astronomers prepared for years for the observations it would make, processing algorithms that tin rapidly crook its information into usable information. Much of the information is unfastened access, allowing the astronomical assemblage to comb done it astir arsenic accelerated arsenic it comes in. Its operators person besides built connected lessons learned from the telescope’s predecessor, Hubble, packing its observational docket arsenic overmuch arsenic possible.

For some, the sheer measurement of bonzer information has been a surprise. “It was much than we expected,” says Heidi Hammel, a NASA interdisciplinary idiosyncratic for JWST and vice president for subject astatine the Association of Universities for Research successful Astronomy successful Washington, DC. “Once we went into operational mode, it was conscionable nonstop. Every hr we were looking astatine a postulation oregon an exoplanet oregon prima formation. It was similar a firehose.”

Now, months later, JWST continues to nonstop down reams of information to astonished astronomers connected Earth, and it is expected to alteration our knowing of the distant universe, exoplanets, satellite formation, galactic structure, and overmuch more. Not each person enjoyed the flurry of activity, which astatine times has reflected an accent connected velocity implicit the technological process, but there’s nary uncertainty that JWST is enchanting audiences crossed the globe astatine a tremendous pace. The floodgates person opened—and they’re not shutting anytime soon.

Opening the pipe

JWST orbits the prima astir a unchangeable constituent 1.5 cardinal kilometers from Earth. Its elephantine gold-coated superior mirror, which is arsenic gangly arsenic a giraffe, is protected from the sun’s glare by a tennis-court-size sunshield, allowing unprecedented views of the beingness successful infrared light.

The scope was a agelong clip coming. First conceived successful the 1980s, it was erstwhile planned for motorboat around 2007 astatine a outgo of $1 billion. But its complexity caused extended delays, devouring wealth until astatine 1 constituent it was dubbed “the scope that ate astronomy.” When JWST yet launched, successful December 2021, its estimated outgo had ballooned to nearly $10 billion. 

Even post-launch, determination person been anxious moments. The telescope’s travel to its people determination beyond the moon’s orbit took a month, and hundreds of moving parts were required to deploy its assorted components, including its tremendous sunshield, which is needed to support the infrared-­sensitive instruments cool.

The purpose is to support the scope arsenic engaged arsenic possible: “The worst happening we could bash is person an idle telescope.”

But by now, the delays, the fund overruns, and astir of the tensions person been overcome. JWST is hard astatine work, its activities cautiously choreographed by the Space Telescope Science Institute (STScI) successful Baltimore. Every week, a squad plans retired the telescope’s upcoming observations, pulling from a semipermanent docket of hundreds of approved programs to beryllium tally successful its archetypal twelvemonth of science, from July 2022 to June 2023.

The purpose is to support the scope arsenic engaged arsenic possible. “The worst happening we could bash is person an idle telescope,” says Dave Adler astatine STScI, the caput of long-range readying for JWST. “It’s not a inexpensive thing.” In the 1990s, Hubble would occasionally find itself twiddling its thumbs successful abstraction if programs were altered oregon canceled; JWST’s docket is deliberately oversubscribed to forestall specified issues. Onboard thrusters and absorption wheels, which rotation to alteration the orientation, determination the scope with precision betwixt assorted targets crossed the sky. “The extremity is ever to minimize the magnitude of clip we’re not doing science,” says Adler.

The effect of this packed docket is that each day, JWST tin cod much than 50 gigabytes of data, compared with conscionable 1 oregon 2 gigabytes for Hubble. The data, which contains images and spectroscopic signatures (essentially airy breached isolated into its elements), is fed done an algorithm tally by STScI. Known arsenic a “pipeline,” it turns the telescope’s earthy images and numbers into utile information. Some of this is released instantly connected nationalist servers, wherever it is picked up by anxious scientists oregon adjacent by Twitter bots specified arsenic the JWST Photo Bot. Other information is handed to scientists connected programs that person proprietary windows, enabling them to instrumentality clip analyzing their ain information earlier it is released to the masses.

The galaxies of Stephan's Quintet, successful an representation created with information from 2 of JWST's infrared instruments. The leftmost postulation appears to beryllium portion of the radical but sits overmuch person to Earth.

NASA, ESA, CSA, STSCI

Pipelines are fundamentally pieces of code, made with programming languages similar Python. They person agelong been utilized successful astronomy but precocious considerably successful 2004  aft astronomers utilized Hubble to walk 1 cardinal seconds observing an bare spot of sky. The extremity was to look for distant galaxies successful the distant universe, but 800 exposures would beryllium taken, truthful Hubble’s planners knew it would beryllium excessively daunting a task to bash by hand.

Instead, they developed a pipeline to crook the exposures into a usable image, a taxing method situation fixed that each representation required its ain calibration and alignment. “There was nary mode you could expect the assemblage astatine that clip to harvester 800 exposures connected their own,” says Anton Koekemoer, a probe astronomer astatine STScI. “The extremity was to alteration subject to beryllium done overmuch much quickly.” The unthinkable representation resulting from those efforts revealed 10,000 galaxies stretching crossed the universe, successful what came to beryllium known arsenic the Hubble Ultra Deep Field. 

With JWST, a azygous maestro pipeline developed by STScI takes images and information from each its instruments and makes them science-ready. Many astronomers, some amateur and professional, past usage their ain pipelines developed successful the months and years earlier motorboat to further analyse the data. That’s wherefore erstwhile JWST’s information began streaming down to Earth, astronomers were capable to astir instantly recognize what they were seeing, turning what would usually beryllium months of investigation clip into conscionable hours of processing time.

“We were sitting determination ready,” says Brammer. “All of a sudden, the tube was open. We were acceptable to go.”

Galaxies everywhere 

Orbiting conscionable a fewer 100 miles supra Earth’s surface, the Hubble Space Telescope is adjacent capable for astronauts to visit. And implicit the years, they did, undertaking a bid of missions to repair and upgrade the telescope, starting with a travel to hole its infamously misshapen mirror—a occupation discovered soon aft motorboat successful 1990. JWST, which sits farther distant than the moon, is connected its own.   

By March, the hold was over. JWST had reached its people determination beyond the moon, and Feinberg and his colleagues were yet acceptable to commencement taking trial images. As helium walked into STScI 1 morning, 1 of those images, a trial representation of a star, was enactment up connected screen. It contained an astonishing surprise. “There were virtually hundreds of galaxies,” says Feinberg. “We were conscionable blown away.” So elaborate was the representation that it revealed galaxies stretching distant into the distant universe, adjacent though it hadn’t been taken for specified a purpose. “Everybody was successful disbelief however good it was working,” helium says.

Following a further process of investigating and calibrating instruments to get the scope up and running, 1 of JWST’s earliest tasks was to look astatine WASP-39b with its cryogenically cooled Mid-Infrared Instrument (MIRI). This instrumentality is the 1 aboard the scope that observes astir profoundly successful the infrared portion of the spectrum, wherever galore of the signatures of planetary atmospheres tin beryllium readily detected. MIRI’s spectrograph allowed scientists to prime isolated the airy from WASP-39b’s atmosphere. Rather than analyzing the observations manually, however, the squad utilized a pipeline called Eureka!, developed by Taylor Bell, an astronomer astatine the Bay Area Environmental Research Institute astatine NASA’s Ames Research Center successful California. “The nonsubjective was to spell from the earthy information that comes down to accusation astir the atmospheric spectrum,” says Bell. Analyzing accusation from an exoplanet similar this would usually necessitate months of work. But wrong hours of the observations, the signature of c dioxide leaped out. A big of different details person since been released astir the planet, including a elaborate investigation of its creation and the beingness of patchy clouds.

Others person utilized pipelines for overmuch much distant targets. In July, studying aboriginal images from JWST, a squad led by Rohan Naidu astatine MIT discovered GLASS-z13, a distant postulation whose airy could day from conscionable 300 cardinal years aft the Big Bang—earlier than immoderate postulation known before. The find caused a global furor due to the fact that it suggested that galaxies whitethorn person formed earlier than antecedently expected, possibly by a fewer 100 cardinal years—meaning our beingness took signifier faster than antecedently believed. 

Naidu’s find was made imaginable by EAZY, a pipeline Brammer developed to somewhat crudely analyse the airy of galaxies successful JWST images. “It estimates the region of the objects utilizing these imaging observations,” says Brammer, who posted the instrumentality connected the bundle website GitHub for anybody to use. 

Rush hour

Traditionally successful science, researchers volition taxable a technological insubstantial to a journal, wherever it is past reviewed by peers successful the tract and yet approved for work oregon rejected. This process tin instrumentality months, adjacent years, sometimes delaying publication—but ever with accuracy and technological rigor successful mind.

There are ways to bypass this process, however. A fashionable method is to station aboriginal versions of technological papers connected the website arXiv anterior to adjacent review. This means that probe tin beryllium work oregon publicized earlier it is published successful a journal. In immoderate cases, the probe is ne'er submitted to a journal, alternatively remaining solely connected arXiv and discussed openly by scientists connected Twitter and different forums.

Posting connected arXiv is fashionable erstwhile determination is simply a caller find that scientists are keen to people quickly, sometimes earlier competing papers travel out. In the lawsuit of JWST, astir a 5th of its first-year programs are unfastened access, meaning the information is instantly released publically erstwhile it is transferred down to Earth. That puts the probe squad that projected the programme successful contiguous contention with others watching the information watercourse in. When the telescope’s firehose of information was switched connected successful July, galore researchers turned to arXiv to people aboriginal results—for amended oregon worse.

“When you’re dealing with thing this caller and this unknown, things should beryllium checked 10 oregon 100 times. That’s not however things went.”

“There was a unreserved to people thing arsenic soon arsenic possible,” says Emiliano Merlin, an astronomer astatine the Astronomical Observatory of Rome who was progressive successful early JWST analysis efforts specified arsenic the contention to find galaxies successful the distant beingness aft the Big Bang. The find of GLASS-z13 and a twelve oregon truthful different intriguing candidates was published earlier follow-up observations could corroborate the property of their light. “It was not thing I personally truly liked,” says Merlin. “When you’re dealing with thing this caller and this unknown, things should beryllium checked 10 oregon 100 times. That’s not however things went.”

One interest was that aboriginal calibration issues with the scope could person resulted successful errors. But truthful acold galore of the aboriginal results person stood up to scrutiny. Follow-up observations person confirmed GLASS-z13 to beryllium a record-breaking aboriginal galaxy, though its property has been somewhat reduced, starring to a renaming of the postulation to GLASS-z12. The imaginable find of different galaxies that formed adjacent earlier than GLASS-z12 suggests that our knowing of however operation emerged successful the beingness whitethorn precise apt request to beryllium rethought, possibly adjacent hinting astatine more extremist models for the aboriginal universe.  

Segments of JWST's superior reflector are prepped for cryogenic investigating successful 2011. The afloat mirror, made of gold-coated beryllium, consists of 18 segments and spans 6.5 meters. It was designed to beryllium folded up for launch.

NASA/MSFC/DAVID HIGGINBOTHAM

While galore of JWST’s programs publically merchandise information immediately, sometimes resulting successful a frantic unreserved to station results early, astir 80% of them person a proprietary period, allowing the researchers moving them exclusive entree to their information for 12 months. This enables scientists, particularly smaller groups that deficiency the resources of ample institutions, to much cautiously scrutinize their ain information earlier releasing it to the public.

“Proprietary clip evens retired the lumps and bumps successful resources,” says Mark McCaughrean, elder advisor for subject and exploration astatine the European Space Agency and a JWST scientist. “If you instrumentality distant proprietary periods, you stack it backmost successful the absorption of the large teams.”

Many scientists bash not usage their afloat 12-month allocation, however, which means they volition lone adhd to the changeless watercourse of discoveries from JWST. Alongside the open-access observations being taken, determination volition beryllium much and much proprietary results released to the public. “Now that the firehose is open, we volition beryllium seeing papers continuously for the adjacent 10 years and beyond,” says Hammel. Perhaps good past that—Feinberg says the scope whitethorn person much than 20 years of fuel, allowing operations to proceed acold into the 2040s.

“We’re cracking unfastened an wholly caller model connected the universe,” says Hammel. “That’s conscionable a truly breathtaking infinitesimal to beryllium a portion of, for america arsenic a species.” 

A mentation of this communicative appeared successful the January/February 2023 issue of the magazine.