Webb telescope probably didn't find life on an exoplanet -- yet

Recent reports of NASA's James Webb Space Telescope finding signs of life on a distant planet understandably sparked excitement. A new study challenges this finding, but also outlines how the telescope might verify the presence of the life-produced gas.

The UC Riverside study, published in the Astrophysical Journal Letters, may be a disappointment to extraterrestrial enthusiasts but does not rule out the near-future possibility of discovery.

In 2023 there were tantalizing reports of a biosignature gas in the atmosphere of planet K2-18b, which seemed to have several conditions that would make life possible.

Many exoplanets, meaning planets orbiting other stars, are not easily comparable to Earth. Their temperatures, atmospheres, and climates make it hard to imagine Earth-type life on them.

However, K2-18b is a bit different. "This planet gets almost the same amount of solar radiation as Earth. And if atmosphere is removed as a factor, K2-18b has a temperature close to Earth's, which is also an ideal situation in which to find life," said UCR project scientist and paper author Shang-Min Tsai.

K2-18b's atmosphere is mainly hydrogen, unlike our nitrogen-based atmosphere. But there was speculation that K2-18b has water oceans, like Earth. That makes K2-18b a potentially "Hycean" world, which means a combination of a hydrogen atmosphere and water oceans.

Last year, a Cambridge team revealed methane and carbon dioxide in the atmosphere of K2-18b using JWST -- other elements that could point to signs of life.

"What was icing on the cake, in terms of the search for life, is that last year these researchers reported a tentative detection of dimethyl sulfide, or DMS, in the atmosphere of that planet, which is produced by ocean phytoplankton on Earth," Tsai said. DMS is the main source of airborne sulfur on our planet and may play a role in cloud formation.

Because the telescope data were inconclusive, the UCR researchers wanted to understand whether enough DMS could accumulate to detectable levels on K2-18b, which is about 120 light years away from Earth. As with any planet that far away, obtaining physical samples of atmospheric chemicals is impossible.

"The DMS signal from the Webb telescope was not very strong and only showed up in certain ways when analyzing the data," Tsai said. "We wanted to know if we could be sure of what seemed like a hint about DMS."

Based on computer models that account for the physics and chemistry of DMS, as well as the hydrogen-based atmosphere, the researchers found that it is unlikely the data show the presence of DMS. "The signal strongly overlaps with methane, and we think that picking out DMS from methane is beyond this instrument's capability," Tsai said.

However, the researchers believe it is possible for DMS to accumulate to detectable levels. For that to happen, plankton or some other life form would have to produce 20 times more DMS than is present on Earth.

Detecting life on exoplanets is a daunting task, given their distance from Earth. To find DMS, the Webb telescope would need to use an instrument better able to detect infrared wavelengths in the atmosphere than the one used last year. Fortunately, the telescope will use such an instrument later this year, revealing definitively whether DMS exists on K2-18b.

"The best biosignatures on an exoplanet may differ significantly from those we find most abundant on Earth today. On a planet with a hydrogen-rich atmosphere, we may be more likely to find DMS made by life instead of oxygen made by plants and bacteria as on Earth," said UCR astrobiologist Eddie Schwieterman, a senior author of the study.

Given the complexities of searching far-flung planets for signs of life, some wonder about the researchers continued motivations.

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Physicists solve puzzle about ancient galaxy found by Webb telescope

Last September, the James Webb Space Telescope, or JWST, discovered JWST-ER1g, a massive ancient galaxy that formed when the universe was just a quarter of its current age. Surprisingly, an Einstein ring is associated with this galaxy. That's because JWST-ER1g acts as a lens and bends light from a distant source, which then appears as a ring -- a phenomenon called strong gravitational lensing, predicted in Einstein's theory of general relativity.

The total mass enclosed within the Einstein radius -- the radius of the Einstein ring -- has two components: stellar and dark matter components.

"If we subtract the stellar mass from the total mass, we get the dark matter mass within the Einstein radius," said Hai-Bo Yu, a professor of physics and astronomy at the University of California, Riverside, whose team has published new work about JWST-ER1g in the journal The Astrophysical Journal Letters. "But the value for the dark matter mass seems higher than expected. This is puzzling. In our paper, we offer an explanation."

A dark matter halo is the halo of invisible matter that permeates and surrounds a galaxy like JWST-ER1g. Although dark matter has never been detected in laboratories, physicists are confident dark matter, which makes up 85% of the universe's matter, exists.

"When ordinary matter -- pristine gas and stars -- collapses and condenses into the dark matter halo of JWST-ER1g, it may be compressing the halo, leading to a high density," said Demao Kong, a second-year graduate student at UCR, who led the analysis. "Our numerical studies show that this mechanism can explain the high dark matter density of JWST-ER1g -- more dark matter mass in the same volume, resulting in higher density."

According to Daneng Yang, a postdoctoral researcher at UCR and co-author on the paper, JWST-ER1g, formed 3.4 billion years after the Big Bang, provides "a great chance to learn about dark matter."

"This strong lensing object is unique because it has a perfect Einstein ring, from which we can obtain valuable information about the total mass within the Einstein radius, a critical step for testing dark matter properties," he said.

Launched on Christmas Day in 2021, NASA's JWST is an orbiting infrared observatory. Also called Webb, it is designed to answer questions about the universe. It is the largest, most complex, and powerful space telescope ever built.

"JWST provides an unprecedented opportunity for us to observe ancient galaxies formed when the universe was young," Yu said. "We expect to see more surprises from JWST and learn more about dark matter soon."

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Webb celebrates first year of science with close-up on birth of sun-like stars

From our cosmic backyard in the solar system to distant galaxies near the dawn of time, NASA's James Webb Space Telescope has delivered on its promise of revealing the universe like never before in its first year of science operations. To celebrate the completion of a successful first year, NASA has released Webb's image of a small star-forming region in the Rho Ophiuchi cloud complex.

"In just one year, the James Webb Space Telescope has transformed humanity's view of the cosmos, peering into dust clouds and seeing light from faraway corners of the universe for the very first time. Every new image is a new discovery, empowering scientists around the globe to ask and answer questions they once could never dream of," said NASA Administrator Bill Nelson. "Webb is an investment in American innovation but also a scientific feat made possible with NASA's international partners that share a can-do spirit to push the boundaries of what is known to be possible. Thousands of engineers, scientists, and leaders poured their life's passion into this mission, and their efforts will continue to improve our understanding of the origins of the universe -- and our place in it."

The new Webb image released today features the nearest star-forming region to us. Its proximity at 390 light-years allows for a highly detailed close-up, with no foreground stars in the intervening space.

"On its first anniversary, the James Webb Space Telescope has already delivered upon its promise to unfold the universe, gifting humanity with a breathtaking treasure trove of images and science that will last for decades," said Nicola Fox, associate administrator of NASA's Science Mission Directorate in Washington. "An engineering marvel built by the world's leading scientists and engineers, Webb has given us a more intricate understanding of galaxies, stars, and the atmospheres of planets outside of our solar system than ever before, laying the groundwork for NASA to lead the world in a new era of scientific discovery and the search for habitable worlds."

Webb's image shows a region containing approximately 50 young stars, all of them similar in mass to the Sun, or smaller. The darkest areas are the densest, where thick dust cocoons still-forming protostars. Huge bipolar jets of molecular hydrogen, represented in red, dominate the image, appearing horizontally across the upper third and vertically on the right. These occur when a star first bursts through its natal envelope of cosmic dust, shooting out a pair of opposing jets into space like a newborn first stretching her arms out into the world. In contrast, the star S1 has carved out a glowing cave of dust in the lower half of the image. It is the only star in the image that is significantly more massive than the Sun.

"Webb's image of Rho Ophiuchi allows us to witness a very brief period in the stellar lifecycle with new clarity. Our own Sun experienced a phase like this, long ago, and now we have the technology to see the beginning of another's star's story," said Klaus Pontoppidan, who served as Webb project scientist at the Space Telescope Science Institute in Baltimore, Maryland, since before the telescope's launch and through the first year of operations.

Some stars in the image display tell-tale shadows indicating protoplanetary disks -- potential future planetary systems in the making.

A Full Year, Across the Full Sky

From its very first deep field image, unveiled by President Joe Biden, Vice President Kamala Harris, and Nelson live at the White House, Webb has delivered on its promise to show us more of the universe than ever before. However, Webb revealed much more than distant galaxies in the early universe.

"The breadth of science Webb is capable of exploring really becomes clear now, when we have a full year's worth of data from targets across the sky," said Eric Smith, associate director for research in the Astrophysics Division at NASA Headquarters and Webb program scientist. "Webb's first year of science has not only taught us new things about our universe, but it has revealed the capabilities of the telescope to be greater than our expectations, meaning future discoveries will be even more amazing." The global astronomy community has spent the past year excitedly poring over Webb's initial public data and getting a feel for how to work with it.

Beyond the stunning infrared images, what really has scientists excited are Webb's crisp spectra -- the detailed information that can be gleaned from light by the telescope's spectroscopic instruments. Webb's spectra have confirmed the distances of some of the farthest galaxies ever observed, and have discovered the earliest, most distant supermassive black holes. They have identified the compositions of planet atmospheres (or lack thereof) with more detail than ever before, and have narrowed down what kinds of atmospheres may exist on rocky exoplanets for the first time. They also have revealed the chemical makeup of stellar nurseries and protoplanetary disks, detecting water, organic carbon-containing molecules, and more. Already, Webb observations have resulted in hundreds of scientific papers answering longstanding questions and raising new ones to address with Webb.

The breadth of Webb science is also apparent in its observations of the region of space we are most familiar with -- our own solar system. Faint rings of gas giants appear out of the darkness, dotted by moons, while in the background Webb shows distant galaxies. By comparing detections of water and other molecules in our solar system with those found in the disks of other, much younger planetary systems, Webb is helping to build up clues about our own origins -- how Earth became the ideal place for life as we know it.

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Webb Telescope detects most distant active supermassive black hole

Researchers have discovered the most distant active supermassive black hole to date with the James Webb Space Telescope (JWST). The galaxy, CEERS 1019, existed about 570 million years after the big bang, and its black hole is less massive than any other yet identified in the early universe.

In addition to the black hole in CEERS 1019, the researchers identified two more black holes that are on the smaller side and existed 1 billion and 1.1 billion years after the big bang. JWST also identified eleven galaxies that existed when the universe was 470 million to 675 million years old. The evidence was provided by JWST's Cosmic Evolution Early Release Science (CEERS) Survey, led by Steven Finkelstein, a professor of astronomy at The University of Texas at Austin. The program combines JWST's highly detailed near- and mid-infrared images and data known as spectra, all of which were used to make these discoveries.

"Looking at this distant object with this telescope is a lot like looking at data from black holes that exist in galaxies near our own," said Rebecca Larson, a recent Ph.D. graduate at UT Austin, who led the study. "There are so many spectral lines to analyze!"

The team has published these results in several initial papers in a special edition of The Astrophysical Journal Letters.

CEERS 1019 is notable not only for how long ago it existed, but also how relatively little its black hole weighs. It clocks in around 9 million solar masses, far less than other black holes that also existed in the early universe and were detected by other telescopes. Those behemoths typically contain more than 1 billion times the mass of the sun -- and they are easier to detect because they are much brighter. The black hole within CEERS 1019 is more like the black hole at the center of our Milky Way galaxy, which is 4.6 million times the mass of the sun.

Though smaller, this black hole existed so much earlier that it is still difficult to explain how it formed so soon after the universe began. Researchers have long known that smaller black holes must have existed earlier in the universe, but it wasn't until JWST began observing that they were able to make definitive detections.

Not only could the team untangle which emissions in the spectrum are from the black hole and which are from its host galaxy, they could also pinpoint how much gas the black hole is ingesting and determine its galaxy's star-formation rate.

The team found this galaxy is ingesting as much gas as it can while also churning out new stars. They turned to the images to explore why that might be. Visually, CEERS 1019 appears as three bright clumps, not a single circular disk.

"We're not used to seeing so much structure in images at these distances," said CEERS team member Jeyhan Kartaltepe, an associate professor of astronomy at the Rochester Institute of Technology in New York. "A galaxy merger could be partly responsible for fueling the activity in this galaxy's black hole, and that could also lead to increased star formation."

These are only the first groundbreaking findings from the CEERS Survey.

"Until now, research about objects in the early universe was largely theoretical," Finkelstein said. "With Webb, not only can we see black holes and galaxies at extreme distances, we can now start to accurately measure them. That's the tremendous power of this telescope."

In the future, it's possible JWST's data may also be used to explain how early black holes formed, revising researchers' models of how black holes grew and evolved in the first several hundred million years of the universe's history.

The James Webb Space Telescope is an international program led by NASA with its partners, the European Space Agency and the Canadian Space Agency.

More Extremely Distant Black Holes and Galaxies

The CEERS Survey is expansive, and there is much more to explore. Team member Dale Kocevski of Colby College in Waterville, Maine, and the team quickly spotted another pair of small black holes in the data. The first, within galaxy CEERS 2782, was easiest to pick out. There isn't any dust obscuring JWST's view of it, so researchers could immediately determine when its black hole existed in the history of the universe -- only 1.1 billion years after the big bang. The second black hole, in galaxy CEERS 746, existed slightly earlier, 1 billion years after the big bang. Its bright accretion disk, a ring made up of gas and dust that encircles its supermassive black hole, is still partially clouded by dust.

"The central black hole is visible, but the presence of dust suggests it might lie within a galaxy that is also furiously pumping out stars," Kocevski explained.

Like the one in CEERS 1019, the two other newly described black holes (in galaxies CEERS 2782 and CEERS 746) are also "light weights" -- at least when compared with previously known supermassive black holes at these distances. They are only about 10 million times the mass of the sun.

"Researchers have long known that there must be lower mass black holes in the early universe. Webb is the first observatory that can capture them so clearly," Kocevski said. "Now we think that lower mass black holes might be all over the place, waiting to be discovered."

Before JWST, all three black holes were too faint to be detected.

"With other telescopes, these targets look like ordinary star-forming galaxies, not active supermassive black holes," Finkelstein added.

JWST's sensitive spectra also allowed these researchers to measure precise distances to, and therefore the ages of, galaxies in the early universe. Team members Pablo Arrabal Haro of the National Science Foundation's NOIRLab and Seiji Fujimoto, a postdoctoral researcher and Hubble fellow at UT Austin, identified 11 galaxies that existed 470 million to 675 million years after the big bang. Not only are they extremely distant, the fact that so many bright galaxies were detected is notable. Researchers theorized that JWST would detect fewer galaxies than are being found at these distances.

"I am overwhelmed by the amount of highly detailed spectra of remote galaxies Webb returned," Arrabal Haro said. "These data are absolutely incredible."

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NIRISS instrument on Webb maps an ultra-hot Jupiter's atmosphere

There's an intriguing exoplanet out there -- 400 light-years out there -- that is so tantalising that astronomers have been studying it since its discovery in 2009. One orbit for WASP-18 b around its star that is slightly larger than our Sun takes just 23 hours. There is nothing like it in our Solar System. A new study led by Université de Montréal Ph.D. student Louis-Philippe Coulombe about this exoplanet, an ultra-hot gas giant 10 times more massive than Jupiter, based on new data from the Canadian NIRISS instrument on the James Webb Space Telescope (JWST) holds many surprises!

Mapping an exoplanet

An international team of astronomers have identified water vapor in the atmosphere of the exoplanet WASP-18 b and made a temperature map of the planet as it slipped behind, and reappeared from, its star. This event is known as a secondary eclipse. Scientists can read the combined light from the star and planet, then refine the measurements from just the star as the planet moves behind it.

The same side, known as the dayside, of WASP-18 b always faces its star, just as the same side of the Moon always faces Earth. This is called tidal locking. The temperature, or brightness, map of the exoplanet shows a huge change in temperature -- up to 1,000 degrees -- from the hottest point facing the star to the terminator, where day and night sides of the tidally-locked planet meet in permanent twilight.

''JWST is giving us the sensitivity to make much more detailed maps of hot giant planets like WASP-18 b than ever before. This is the first time a planet has been mapped with JWST, and it's really exciting to see that some of what our models predicted, such as a sharp drop in temperature away from the point on the planet directly facing the star, is actually seen in the data!'' said Megan Mansfield, a Sagan Fellow at the University of Arizona, and one of the authors of the paper describing the results.

The team mapped temperature gradients across the day side of the planet. Given how much cooler the planet is at the terminator, there is likely something hindering winds from efficiently redistributing heat to the night side. But what is affecting the winds is still a mystery.

''The brightness map of WASP-18 b shows a lack of east-west winds that is best matched by models with atmospheric drag. One possible explanation is that this planet has a strong magnetic field, which would be an exciting discovery!'' said co-author Ryan Challener, of the University of Michigan.

One interpretation of the eclipse map is that magnetic effects force the winds to blow from the planet's equator up over the North pole and down over the South pole, instead of East-West, as we would otherwise expect.

Researchers recorded temperature changes at different elevations of the gas giant planet's layers of atmosphere. They saw temperatures increase with elevation, varying by hundreds of degrees.

Signs of water vapor

The spectrum of the planet's atmosphere clearly shows multiple small but precisely measured water features, present despite the extreme temperatures of almost 2,700 degrees Celsius. It is so hot that it would tear most water molecules apart, so still seeing its presence speaks to Webb's extraordinary sensitivity to detect remaining water. The amounts recorded in WASP-18 b's atmosphere indicate water vapor is present at various elevations

''It was a great feeling to look at WASP-18 b's JWST spectrum for the first time and see the subtle but precisely measured signature of water,'' said Louis-Philippe Coulombe, a Ph.D. student at the Université de Montréal, member of the Trottier Institute for Research on Exoplanets (iREx) and lead author of the WASP-18 b paper. ''Using this kind of measurements, we will be able to detect such molecules for a wide range of planets in the years to come!'', added Björn Benneke, UdeM Professor, iREx member and co-author of this paper. Benneke is Coulombe's Ph.D. advisor as well and has been leading worldwide efforts to study WASP-18 b since 2016.

The work of the NIRISS instrument and early career scientists

The team of astronomers observed WASP-18 b for about six hours using one of Webb's instruments, the Near-Infrared Imager and Slitless Spectrograph (NIRISS), contributed by the Canadian Space Agency and several partners including the Université de Montréal and iREx.

''Because the water features in this spectrum are so subtle, they were difficult to identify in previous observations. That made it really exciting to finally see water features with these JWST observations,'' said Anjali Piette, a postdoctoral fellow at the Carnegie Institution for Science and one of the authors of the new research.

The WASP-18 b observations were collected as part of the Transiting Exoplanet Community Early Release Science Program led by Natalie Batalha, an astronomer at the University of California, Santa Cruz, who helped coordinate the new research and the more than one hundred researchers in the team. Much of this ground-breaking work is being done by early career scientists like Coulombe, Challener, Piette, and Mansfield.

Proximity, both to its star and to us, helped make WASP-18 b such an intriguing target for these scientists, as did its large mass. WASP-18 b is one of the most massive worlds whose atmospheres we can investigate. Astronomers are striving to understand how such planets form and come to be where they are in their systems. This, too, has some early answers from Webb.

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Webb Telescope captures rarely seen prelude to supernova

The rare sight of a Wolf-Rayet star -- among the most luminous, most massive, and most briefly detectable stars known -- was one of the first observations made by NASA's James Webb Space Telescope in June 2022. Webb shows the star, WR 124, in unprecedented detail with its powerful infrared instruments. The star is 15,000 light-years away in the constellation Sagittarius.

Massive stars race through their lifecycles, and only some of them go through a brief Wolf-Rayet phase before going supernova, making Webb's detailed observations of this rare phase valuable to astronomers. Wolf-Rayet stars are in the process of casting off their outer layers, resulting in their characteristic halos of gas and dust. The star WR 124 is 30 times the mass of the Sun and has shed 10 Suns' worth of material -- so far. As the ejected gas moves away from the star and cools, cosmic dust forms and glows in the infrared light detectable by Webb.

The origin of cosmic dust that can survive a supernova blast and contribute to the universe's overall "dust budget" is of great interest to astronomers for multiple reasons. Dust is integral to the workings of the universe: It shelters forming stars, gathers together to help form planets, and serves as a platform for molecules to form and clump together -- including the building blocks of life on Earth. Despite the many essential roles that dust plays, there is still more dust in the universe than astronomers' current dust-formation theories can explain. The universe is operating with a dust budget surplus.

Webb opens up new possibilities for studying details in cosmic dust, which is best observed in infrared wavelengths of light. Webb's Near-Infrared Camera (NIRCam) balances the brightness of WR 124's stellar core and the knotty details in the fainter surrounding gas. The telescope's Mid-Infrared Instrument (MIRI) reveals the clumpy structure of the gas and dust nebula of the ejected material now surrounding the star. Before Webb, dust-loving astronomers simply did not have enough detailed information to explore questions of dust production in environments like WR 124, and whether the dust grains were large and bountiful enough to survive the supernova and become a significant contribution to the overall dust budget. Now those questions can be investigated with real data.

Stars like WR 124 also serve as an analog to help astronomers understand a crucial period in the early history of the universe. Similar dying stars first seeded the young universe with heavy elements forged in their cores -- elements that are now common in the current era, including on Earth.

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Webb, Hubble capture detailed views of DART impact

Two of NASA's Great Observatories, the James Webb Space Telescope and the Hubble Space Telescope, have captured views of a unique NASA experiment designed to intentionally smash a spacecraft into a small asteroid in the world's first-ever in-space test for planetary defense. These observations of NASA's Double Asteroid Redirection Test (DART) impact mark the first time that Webb and Hubble simultaneously observed the same celestial target.

On Sept. 26, 2022, at 7:14 pm EDT, DART intentionally crashed into Dimorphos, the asteroid moonlet in the double-asteroid system of Didymos. It was the world's first test of the kinetic impact mitigation technique, using a spacecraft to deflect an asteroid that poses no threat to Earth, and modifying the object's orbit. DART is a test for defending Earth against potential asteroid or comet hazards.

The coordinated Hubble and Webb observations are more than just an operational milestone for each telescope -- there are also key science questions relating to the makeup and history of our solar system that researchers can explore when combining the capabilities of these observatories.

"Webb and Hubble show what we've always known to be true at NASA: We learn more when we work together," said NASA Administrator Bill Nelson. "For the first time, Webb and Hubble have simultaneously captured imagery from the same target in the cosmos: an asteroid that was impacted by a spacecraft after a seven-million-mile journey. All of humanity eagerly awaits the discoveries to come from Webb, Hubble, and our ground-based telescopes -- about the DART mission and beyond."

Observations from Webb and Hubble together will allow scientists to gain knowledge about the nature of the surface of Dimorphos, how much material was ejected by the collision, and how fast it was ejected. Additionally, Webb and Hubble captured the impact in different wavelengths of light -- Webb in infrared and Hubble in visible. Observing the impact across a wide array of wavelengths will reveal the distribution of particle sizes in the expanding dust cloud, helping to determine whether it threw off lots of big chunks or mostly fine dust. Combining this information, along with ground-based telescope observations, will help scientists to understand how effectively a kinetic impact can modify an asteroid's orbit.

Webb Captures Impact Site Before and After Collision

Webb took one observation of the impact location before the collision took place, then several observations over the next few hours. Images from Webb's Near-Infrared Camera (NIRCam) show a tight, compact core, with plumes of material appearing as wisps streaming away from the center of where the impact took place.

Observing the impact with Webb presented the flight operations, planning, and science teams with unique challenges, because of the asteroid's speed of travel across the sky. As DART approached its target, the teams performed additional work in the weeks leading up to the impact to enable and test a method of tracking asteroids moving over three times faster than the original speed limit set for Webb.

"I have nothing but tremendous admiration for the Webb Mission Operations folks that made this a reality," said principal investigator Cristina Thomas of Northern Arizona University in Flagstaff, Arizona. "We have been planning these observations for years, then in detail for weeks, and I'm tremendously happy this has come to fruition."

Scientists also plan to observe the asteroid system in the coming months using Webb's Mid-Infrared Instrument (MIRI) and Webb's Near-Infrared Spectrograph (NIRSpec). Spectroscopic data will provide researchers with insight into the asteroid's chemical composition.

Webb observed the impact over five hours total and captured 10 images. The data was collected as part of Webb's Cycle 1 Guaranteed Time Observation Program 1245 led by Heidi Hammel of the Association of Universities for Research in Astronomy (AURA).

Hubble Images Show Movement of Ejecta After Impact

Hubble also captured observations of the binary system ahead of the impact, then again 15 minutes after DART hit the surface of Dimorphos. Images from Hubble's Wide Field Camera 3 show the impact in visible light. Ejecta from the impact appear as rays stretching out from the body of the asteroid. The bolder, fanned-out spike of ejecta to the left of the asteroid is in the general direction from which DART approached.

Some of the rays appear to be curved slightly, but astronomers need to take a closer look to determine what this could mean. In the Hubble images, astronomers estimate that the brightness of the system increased by three times after impact, and saw that brightness hold steady, even eight hours after impact.

Hubble plans to monitor the Didymos-Dimorphos system 10 more times over the next three weeks. These regular, relatively long-term observations as the ejecta cloud expands and fades over time will paint a more complete picture of the cloud's expansion from the ejection to its disappearance.

"When I saw the data, I was literally speechless, stunned by the amazing detail of the ejecta that Hubble captured," said Jian-Yang Li of the Planetary Science Institute in Tucson, Arizona, who led the Hubble observations. "I feel lucky to witness this moment and be part of the team that made this happen."

Hubble captured 45 images in the time immediately before and following DART's impact with Dimorphos. The Hubble data was collected as part of Cycle 29 General Observers Program 16674.

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Webb reveals a galaxy sparkling with the universe's oldest star clusters

Using the James Webb Space Telescope (JWST), researchers from the CAnadian NIRISS Unbiased Cluster Survey (CANUCS) team have identified the most distant globular clusters ever discovered. These dense groups of millions of stars may be relics that contain the first and oldest stars in the universe.

The early analysis of Webb's First Deep Field image, which depicts some of the universe's earliest galaxies, is published today in The Astrophysical Journal Letters.

"JWST was built to find the first stars and the first galaxies and to help us understand the origins of complexity in the universe, such as the chemical elements and the building blocks of life," says Lamiya Mowla, Dunlap Fellow at the Dunlap Institute for Astronomy & Astrophysics at the University of Toronto and co-lead author of the study. "This discovery in Webb's First Deep Field is already providing a detailed look at the earliest phase of star formation, confirming the incredible power of JWST."

In the finely detailed Webb's First Deep Field image, the researchers zeroed in on what they've dubbed "the Sparkler galaxy," which is nine billion light years away. This galaxy got its name for the compact objects appearing as small yellow-red dots surrounding it, referred to by the researchers as "sparkles." The team posited that these sparkles could either be young clusters actively forming stars -- born three billion years after the Big Bang at the peak of star formation -- or old globular clusters. Globular clusters are ancient collections of stars from a galaxy's infancy and contain clues about its earliest phases of formation and growth.

From their initial analysis of 12 of these compact objects, the researchers determined that five of them are not only globular clusters but among the oldest ones known.

"Looking at the first images from JWST and discovering old globular clusters around distant galaxies was an incredible moment, one that wasn't possible with previous Hubble Space Telescope imaging," says Kartheik G. Iyer, Dunlap Fellow at the Dunlap Institute for Astronomy & Astrophysics at the University of Toronto and co-lead author of the study. "Since we could observe the sparkles across a range of wavelengths, we could model them and better understand their physical properties, like how old they are and how many stars they contain. We hope the knowledge that globular clusters can be observed at from such great distances with JWST will spur further science and searches for similar objects."

The Milky Way galaxy has about 150 globular clusters, and how and when exactly these dense clumps of stars formed is not well understood. Astronomers know that globular clusters can be extremely old, but it is incredibly challenging to measure their ages. Using very distant globular clusters to age-date the first stars in distant galaxies has not been done before and is only possible with JWST.

"These newly identified clusters were formed close to the first time it was even possible to form stars," says Mowla. "Because the Sparkler galaxy is much farther away than our own Milky Way, it is easier to determine the ages of its globular clusters. We are observing the Sparkler as it was nine billion years ago, when the universe was only four-and-a-half billion years old, looking at something that happened a long time ago. Think of it as guessing a person's age based on their appearance -- it's easy to tell the difference between a 5- and 10-year-old, but hard to tell the difference between a 50- and 55-year-old."

Until now, astronomers could not see the surrounding compact objects of the Sparkler galaxy with the Hubble Space Telescope (HST). This changed with JWST's increased resolution and sensitivity, unveiling the tiny dots surrounding the galaxy for the first time in Webb's First Deep Field image. The Sparkler galaxy is special because it is magnified by a factor of 100 due to an effect called gravitational lensing -- where the SMACS 0723 galaxy cluster in the foreground distorts what is behind it, much like a giant magnifying glass. Moreover, gravitational lensing produces three separate images of the Sparkler, allowing astronomers to study the galaxy in greater detail.

"Our study of the Sparkler highlights the tremendous power in combining the unique capabilities of JWST with the natural magnification afforded by gravitational lensing," says CANUCS team lead Chris Willott from the National Research Council's Herzberg Astronomy and Astrophysics Research Centre. "The team is excited about more discoveries to come when JWST turns its eye on the CANUCS galaxy clusters next month."

The researchers combined new data from JWST's Near-Infrared Camera (NIRCam) with HST archival data. NIRCam detects faint objects using longer and redder wavelengths to observe past what is visible to the human eye and even HST. Both magnifications due to the lensing by the galaxy cluster and the high resolution of JWST are what made observing compact objects possible.

The Canadian-made Near-Infrared Imager and Slitless Spectrograph (NIRISS) instrument on the JWST provided independent confirmationthat the objects are old globular clusters because the researchers did not observe oxygen emission lines -- emissions with measurable spectra given off by young clusters that are actively forming stars. NIRISS also helped unravel the geometry of the triply lensed images of the Sparkler.

"JWST's made-in-Canada NIRISS instrument was vital in helping us understand how the three images of the Sparkler and its globular clusters are connected," says Marcin Sawicki, Canada Research Chair in Astronomy, professor at Saint Mary's University and study co-author. "Seeing several of the Sparkler's globular clusters imaged three times made it clear that they are orbiting around the Sparkler galaxy rather than being simply in front of it by chance."

JWST will observe the CANUCS fields starting in October 2022, leveraging JWST data to examine five massive clusters of galaxies, around which the researchers expect to find more such systems. Future studies will also model the galaxy cluster to understand the lensing effect and execute more robust analyses to explain the star formation histories.

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NASA Reveals Webb Telescope's first images of unseen universe

 The dawn of a new era in astronomy is here as the world gets its first look at the full capabilities of NASA's James Webb Space Telescope, a partnership with ESA (European Space Agency) and CSA (Canadian Space Agency).

The full set of the telescope's first full-color images and spectroscopic data, which uncover a collection of cosmic features elusive until now, released Tuesday, are available at:

https://www.nasa.gov/webbfirstimages

"Today, we present humanity with a groundbreaking new view of the cosmos from the James Webb Space Telescope -- a view the world has never seen before," said NASA Administrator Bill Nelson. "These images, including the deepest infrared view of our universe that has ever been taken, show us how Webb will help to uncover the answers to questions we don't even yet know to ask; questions that will help us better understand our universe and humanity's place within it.

"The Webb team's incredible success is a reflection of what NASA does best. We take dreams and turn them into reality for the benefit of humanity. I can't wait to see the discoveries that we uncover -- the team is just getting started!"

NASA explores the unknown in space for the benefit of all, and Webb's first observations tell the story of the hidden universe through every phase of cosmic history -- from neighboring planets outside our solar system, known as exoplanets, to the most distant observable galaxies in the early universe.

"This is a singular and historic moment," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate. "It took decades of drive and perseverance to get us here, and I am immensely proud of the Webb team. These first images show us how much we can accomplish when we come together behind a shared goal, to solve the cosmic mysteries that connect us all. It's a stunning glimpse of the insights yet to come."

"We are elated to celebrate this extraordinary day with the world," said Greg Robinson, Webb program director at NASA Headquarters. "The beautiful diversity and incredible detail of the Webb telescope's images and data will have a profound impact on our understanding of the universe and inspire us to dream big."

Webb's first observations were selected by a group of representatives from NASA, ESA, CSA, and the Space Telescope Science Institute. They reveal the capabilities of all four of Webb's state-of-the-art scientific instruments:
 

• SMACS 0723: Webb has delivered the deepest and sharpest infrared image of the distant universe so far -- and in only 12.5 hours. For a person standing on Earth looking up, the field of view for this new image, a color composite of multiple exposures each about two hours long, is approximately the size of a grain of sand held at arm's length. This deep field uses a lensing galaxy cluster to find some of the most distant galaxies ever detected. This image only scratches the surface of Webb's capabilities in studying deep fields and tracing galaxies back to the beginning of cosmic time.
• WASP-96b (spectrum): Webb's detailed observation of this hot, puffy planet outside our solar system reveals the clear signature of water, along with evidence of haze and clouds that previous studies of this planet did not detect. With Webb's first detection of water in the atmosphere of an exoplanet, it will now set out to study hundreds of other systems to understand what other planetary atmospheres are made of.
• Southern Ring Nebula: This planetary nebula, an expanding cloud of gas that surrounds a dying star, is approximately 2,000 light years away. Here, Webb's powerful infrared eyes bring a second dying star into full view for the first time. From birth to death as a planetary nebula, Webb can explore the expelling shells of dust and gas of aging stars that may one day become a new star or planet.
• Stephan's Quintet: Webb's view of this compact group of galaxies, located in the constellation Pegasus, pierced through the shroud of dust surrounding the center of one galaxy, to reveal the velocity and composition of the gas near its supermassive black hole. Now, scientists can get a rare look, in unprecedented detail, at how interacting galaxies are triggering star formation in each other and how the gas in these galaxies is being disturbed.
• Carina Nebula: Webb's look at the 'Cosmic Cliffs' in the Carina Nebula unveils the earliest, rapid phases of star formation that were previously hidden. Looking at this star-forming region in the southern constellation Carina, as well as others like it, Webb can see newly forming stars and study the gas and dust that made them.

"Absolutely thrilling!" said John Mather, Webb senior project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The equipment is working perfectly, and nature is full of surprising beauty. Congratulations and thanks to our worldwide teams that made it possible."

The release of Webb's first images and spectra kicks off the beginning of Webb's science operations, where astronomers around the world will have their chance to observe anything from objects within our solar system to the early universe using Webb's four instruments.

The James Webb Space Telescope launched Dec. 25, 2021, on an Ariane 5 rocket from Europe's Spaceport in French Guiana, South America. After completing a complex deployment sequence in space, Webb underwent months of commissioning where its mirrors were aligned, and its instruments were calibrated to its space environment and prepared for science.

The public can also view the new Webb images Tuesday on several digital screens in New York City's Times Square and in London's Piccadilly Circus beginning at 5:30 p.m. EDT and 10:30 p.m. GMT, respectively.

The James Webb Space Telescope is the world's premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars and probe the mysterious structures and origins of our universe and our place in it.

NASA Headquarters oversees the mission for the agency's Science Mission Directorate. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages Webb for the agency and oversees work on the mission performed by the Space Telescope Science Institute, Northrop Grumman, and other mission partners. In addition to Goddard, several NASA centers contributed to the project, including the agency's Johnson Space Center in Houston, Jet Propulsion Laboratory in Southern California, Marshall Space Flight Center in Huntsville, Alabama, Ames Research Center in California's Silicon Valley, and others.

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