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Why the James Webb Space Telescope's amazing 'Pillars of Creation' photo has astronomers buzzing – Space.com

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The James Webb Space Telescope took a breathtaking look inside the “Pillars of Creation,” a spectacular dust cloud formation made famous by its predecessor, the Hubble Space Telescope. 

The image is not only stunningly beautiful but also reveals cosmic processes never before observed with such clarity. Here is what astronomers see behind the sparkling, colorful tapestry.

If you want to properly take in the magic of the James Webb Space Telescope‘s photo of the Pillars of Creation, you have to download the original image from the website of the Space Telescope Science Institute (STScI) in Baltimore, which manages the mission’s science operations. It’s not a small file. At about 150 megabytes, it might clog your internet downlink for a while. Then zoom into the darkest regions at the tops of the pillars. Zoom in a little more, until you see red dots springing into view. There are dozens of them. The smaller ones are just plain red spots. Others are somewhat larger, resembling flowers with yellow centers surrounded by six red petals, and sometimes with Webb’s trademark snowflake-like refraction patterns.

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Related: The James Webb Space Telescope never disproved the Big Bang. Here’s how that falsehood spread.

A star is born …

These floral formations are newborn stars, some of them only a few hundred thousand years old, the creation inside the Pillars of Creation revealed for the first time. For Webb’s predecessor, the Hubble Space Telescope, which observes the universe mostly in visible light (wavelengths that the human eye can see), these pillars were impenetrable, menacing dark formations rising from the Eagle Nebula, a cloudy cluster of stars in the constellation Serpens less than 6,000 light-years away from Earth. But Webb, with its infrared, heat-detecting gaze, peered through the darkness to reveal how light in the universe is being born.

“The most interesting thing about this image is that it’s actually showing us star formation in progress,” Anton Koekemoer, a research astronomer at STScI, told Space.com. 

Koekemoer put the stunning image together from raw data taken by Webb’s powerful NIRCam camera. Amazing imagery of the universe is the daily bread and butter for Koekemoer, who previously worked on processing images from the Hubble Space Telescope. Yet the astronomer admits that the texture, level of detail and amount of scientific information contained in Webb’s photographs stuns even him. 

“I’m amazed at how well Webb can see into the dust and gas that is completely dark with Hubble,” Koekemoer said. “With Hubble, you don’t see any detail at all. But Webb, with its infrared vision, can penetrate directly into these regions and see the stars forming inside those dusty pillars. It’s extremely exciting.”

The Pillars of Creation seen by the James Webb Space Telescope. (Image credit: NASA, ESA, CSA, STScI; Joseph DePasquale (STScI), Anton M. Koekemoer (STScI), Alyssa Pagan (STScI).)

 … from the cold dark dust 

Professor Derek Ward-Thompson shares Koekemoer’s excitement. A veteran astronomer and head of the School of Natural Sciences at the University of Central Lancashire in the U.K., Ward-Thompson has published several scientific papers about the Pillars of Creation over the years, including a few about the powerful magnetic fields that hold the formation together. Yet, he says, his first thought when seeing the first Webb image of his favorite cloud of cosmic hydrogen was rather unscientific. 

“I just thought ‘Wow’,” Ward-Thompson told Space.com. “It really made me understand how the James Webb Space Telescope is going to be so much better than Hubble, which can only see the outside. It also provides a much better detail, much higher resolution.”

Webb’s images, Ward-Thompson said, are providing a unique window into the dark and freezing clouds where stellar embryos are being incubated from a hydrogen-rich dust. For the first time, astronomers can not only theorize about this process but also study it in dozens of examples of various sizes and brightness levels. 

“I’m sure that Webb’s images will advance our understanding of how stars form and, hence, where our own sun came from,” Ward-Thompson.

The red dots visible in Webb’s images are protostars, cocoons of dust and gas so dense that they are collapsing together under the weight of their own gravity. As the clouds collapse, they form rotating balls, which will eventually become so dense that the hydrogen atoms in their cores will begin to fuse together in the process of nuclear fusion, which makes stars shine. 

The protostars that Webb sees are not fully there yet, only beginning to glow in the infrared light as they warm above the coldness of the surrounding cloud, which is no warmer than minus 390 degrees Fahrenheit (minus 200 degrees Celsius), said Ward-Thompson.

“These young stars that we see in the image are not yet burning hydrogen,” Ward-Thompson said. “But gradually, as more and more material falls in, the middle becomes denser and denser, and then suddenly, it becomes so dense that the hydrogen burning switches on, and then suddenly their temperature jumps up to about 2 million degrees Celsius [35 million degrees F].”

In some of the larger bright red patches in the image, several stars are bursting out at once. Elsewhere, their heat has not yet broken through the surrounding dust.

The Pillars of Creation are one of the closest regions of active star formation to Earth, which means that in combination with Webb’s imaging powers, the site provides the best opportunity to study star-forming processes, Ward-Thompson said. 

The iconic Pillars of Creation. The Hubble Space Telescope’s view on the left, the new James Webb Space Telescope photo on the right. (Image credit: NASA, ESA, CSA, STScI; Joseph DePasquale (STScI), Anton M. Koekemoer (STScI), Alyssa Pagan (STScI).)

15,000 pixels 

Each of those red dots that you can only see when you zoom into the image covers an area larger than our solar system. The whole image, 15,000 pixels wide, captures an area some 8 to 9 light years-across. 

“You can resolve things that are about the size of our solar system in the image,” Koekemoer said. “If there were individual planets like Jupiter, you wouldn’t be able to resolve those.”

The image, which Koekemoer assembled from data taken by NIRCam in six different filters, shows the Pillars in different colors than they would appear to the human eye. The only wavelength in the image that the human eye would detect is that of the color red, which is represented as blue in the image

“The yellowish, greenish and ultimately orange and red colors go to the mid-infrared wavelengths,” Koekemoer said. “The longest wavelengths in this image are six times longer than the human eye could see.”

With each color, a different component of the physical processes taking place in the stunning nebula appears. The bluish wisps of gas and dust that emanate like thin veils out of the nebula’s edges are clouds of ionized hydrogen — hydrogen electrons stripped from the colder atomic hydrogen forming the dark dense clouds by intense ultraviolet light streaming from nearby massive stars. 

Ionized hydrogen billowing out of the dense clouds of molecular dust that forms the Pillars of Creation. (Image credit: NASA, ESA, CSA, STScI)

The physics behind the pillars

With Webb’s ability to reveal the structure of the dust clouds with unprecedented nuance and texture, astronomers will also be able to study the processes that sculpted the towering clouds over millions of years. 

“The material that the pillars are made of is what we call the interstellar medium, the medium between the stars,” Ward-Thompson said. “It becomes more transparent as you go to longer [infrared] wavelengths. The Hubble images told us only where the material was, but Webb now shows us where it’s thicker and where it’s thinner. It’s almost like making an X-ray of a human.”

Related stories:

Astronomers know that the Pillars are not a stable cosmic sculpture but rather a constantly changing flow of material, similar to the constantly changing surface of a sandy beach. What shapes the pillars are powerful stellar winds emanating from a cluster of large stars, which is not visible in this image, Ward-Thompson said. Strong cosmic magnetic fields hold the clouds together, protecting them from being dispersed by the stellar winds. Still, within several million years, the Pillars will no longer resemble the iconic images that we see today. 

For Webb, the Pillars are still just the beginning, providing only a glimpse of what the $10 billion telescope can accomplish, Koekemoer said.

“Everybody in the astronomical community is very excited about what the future holds for Webb,” Koekemoer said. “I think there’ll be many more observations coming down the road that will show us even more about how stars and galaxies are forming.”

Follow Tereza Pultarova on Twitter @TerezaPultarova. Follow us on Twitter @Spacedotcom and on Facebook

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NASA capsule flies over Apollo landing sites, heads home – World News – Castanet.net

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NASA’s Orion capsule and its test dummies swooped one last time around the moon Monday, flying over a couple Apollo landing sites before heading home.

Orion will aim for a Pacific splashdown Sunday off San Diego, setting the stage for astronauts on the next flight in a couple years.

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The capsule passed within 80 miles (130 kilometers) of the far side of the moon, using the lunar gravity as a slingshot for the 237,000-mile (380,000-kilometer) ride back to Earth. It spent a week in a wide, sweeping lunar orbit.

Once emerging from behind the moon and regaining communication with flight controllers in Houston, Orion beamed back photos of a close-up moon and a crescent Earth — Earthrise — in the distance.

“Orion now has its sights set on home,” said Mission Control commentator Sandra Jones.

The capsule also passed over the landing sites of Apollo 12 and 14. But at 6,000 miles (9,600 kilometers) up, it was too high to make out the descent stages of the lunar landers or anything else left behind by astronauts more than a half-century ago. During a similar flyover two weeks ago, it was too dark for pictures. This time, it was daylight.

Deputy chief flight director Zebulon Scoville said nearby craters and other geologic features would be visible in any pictures, but little else.

“It will be more of a tip of the hat and a historical nod to the past,” Scoville told reporters last week.

The three-week test flight has exceeded expectations so far, according to officials. But the biggest challenge still lies ahead: hitting the atmosphere at more than 30 times the speed of sound and surviving the fiery reentry.

Orion blasted off Nov. 16 on the debut flight of NASA’s most powerful rocket ever, the Space Launch System or SLS.

The next flight — as early as 2024 — will attempt to carry four astronauts around the moon. The third mission, targeted for 2025, will feature the first lunar landing by astronauts since the Apollo moon program ended 50 years ago this month.

Apollo 17 rocketed away Dec. 7, 1972, from NASA’s Kennedy Space Center, carrying Eugene Cernan, Harrison Schmitt and Ron Evans. Cernan and Schmitt spent three days on the lunar surface, the longest stay of the Apollo era, while Evans orbited the moon. Only Schmitt is still alive.

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By Looking Back Through Hubble Data, Astronomers Have Identified six Massive Stars Before They Exploded as Core-Collapse Supernovae – Universe Today

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The venerable Hubble Space Telescope has given us so much during the history of its service (32 years, 7 months, 6 days, and counting!) Even after all these years, the versatile and sophisticated observatory is still pulling its weight alongside more recent addition, like the James Webb Space Telescope (JWST) and other members of NASA’s Great Observatories family. In addition to how it is still conducting observation campaigns, astronomers and astrophysicists are combing through the volumes of data Hubble accumulated over the years to find even more hidden gems.

A team led by Caltech’s recently made some very interesting finds in the Hubble archives, where they observed the sites of six supernovae to learn more about their progenitor stars. Their observations were part of the Hubble Space Telescope Snapshot program, where astronomers use HST images to chart the life cycle and evolution of stars, galaxies, and other celestial objects. From this, they were able to place constraints on the size, mass, and other key characteristics of the progenitor stars and what they experienced before experiencing core collapse.

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The team was led by Dr. Schuyler D. Van Dyk, a senior research scientist with Caltech’s Infrared Processing and Analysis Center (IPAC). His teammates included researchers from the University of California, Berkeley, the Space Telescope Science Institute, the University of Arizona’s Steward Observatory, the University of Hawai’i’s Institute for Astronomy, and the School of Physics and Astronomy at the University of Minnesota. Their findings were published in a paper titled “The disappearance of six supernova progenitors” that will appear in the Monthly Notices of the Royal Astronomical Society.

The Hubble Ultra Deep Field seen in ultraviolet, visible, and infrared light. Image Credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)

As they indicate in their paper, the targets of their study were all nearby core-collapse supernovae (SNe) that Hubble imaged at high spatial resolutions. The images were part of the Hubble Snapshot program, created by the Space Telescope Science Institute (STScI) to provide a large sample of images for various targets. Every target is observed in a single orbit of Hubble around the Earth between other observation programs, allowing a degree of flexibility that is not possible with other observatories.

For their study, Van Dyk and his colleagues examined images of six extragalactic supernovae before and after they exploded – designated SN 2012A, SN 2013ej, SN 2016gkg, SN 2017eaw, SN 2018zd, and SN 2018aoq. With extragalactic targets, astronomers have difficulty knowing if the stars they identified were progenitors to the supernova, given the distance involved. As Van Dyk to Universe Today via email, the only way to be sure is to wait for the supernova to dim, then confirm that the progenitor star has disappeared:

“Since the supernova explosion is so luminous, we have to wait a number of years until it has faded enough that it is less luminous than was the progenitor. In a few of the cases we show in our paper, there is little question that the star that was there pre-explosion is now gone. In the other cases, we’re reasonably sure, but the supernova is still detectable and is just faint enough for us to infer that the progenitor has vanished. “

In a previous study, Van Dyk and several colleagues who were co-authors of this study investigated another supernova (iPTF13bvn) whose progenitor star disappeared. In this case, the research team relied on data obtained by Hubble of the SN site – as part of the Ultraviolet Ultra Deep Field (UVUDF) campaign – roughly 740 days after the star exploded. In 2013, Van Dyk led a study that used images from an earlier Snapshot program to confirm that the progenitor of SN 2011dh in the Whirlpool Galaxy (Messier 51) had disappeared.

The Whirlpool Galaxy (Spiral Galaxy M51, NGC 5194), a classic spiral galaxy located in the Canes Venatici constellation, and its companion NGC 5195. Credit: NASA/ESA

These and other papers over the years have shown that progenitor candidates can be directly identified from pre-explosion images. In this most recent study, Van Dyk and his colleagues observed supernovae in the later stages of their evolution to learn what mechanisms are powering them. In many cases, the mechanism is the decay of radioactive nuclei (in particular, radioactive nickel, cobalt, and iron) that were synthesized by the enormous energy of the explosion. But as he explained, they suspected that other mechanisms might be involved:

“However, we have indications that some supernovae inevitably have additional power sources — one possibility is that the light of the supernova has been scattered by interstellar dust immediate to the explosion, in the form of a ‘light echo’; another more likely possibility is that the shockwave associated with the explosion is interacting with gas that was deposited around the progenitor star by the star itself during the course of the star’s life, in the form of wind or outburst, that is, circumstellar matter. The ejecta from the explosion moving through and interacting with this circumstellar matter can result in luminous energy that can persist for years, even for decades.”

In short, the team was trying to estimate how many of the supernovae they observed evolved through radioactive decay versus more exotic powering mechanisms. Their results showed that SN 2012A, SN 2018zd, and SN 2018aoq had faded to the point where they were no longer detectable in the Hubble Snapshot images, whereas SN 2013ej, SN 2016gkg, and SN 2017eaw had faded just enough. Therefore, they could infer in all six cases that the progenitors had disappeared. However, not all were the result of a single massive star undergoing core collapse.

In the case of SN 2016gkg, the images acquired by Hubble’s Wide Field Camera 3 (WFC3) were of much higher spatial resolution and sensitivity than the images of the host galaxy, previously taken by the now-retired WFC2. This allowed them to theorize that SN 2016gkg was not the result of a single core-collapse supernova but a progenitor star interacting with a neighboring star. Said Van Dyk:

“So, in the old image, the progenitor looked like one “star,” whereas in the new images, we could see that the progenitor had to have been spatially distinct from the neighboring star. Therefore, we were able to obtain a better estimate of the progenitor’s luminosity and color, now uncontaminated by the neighbor, and from that, we were able to make some new inferences about the overall properties of the progenitor, or, in this case, progenitor system, since we characterized the new results using existing models of binary star systems.”

Artist’s impression of a supernova remnant. Credit: ESA/Hubble

Specifically, they determined that the progenitor belonged to the class of “stripped-envelope” supernovae (SESNe), in which the outer hydrogen H-rich envelope of the progenitor star has been significantly or entirely removed. They further estimated that the progenitor was the primary and its companion was likely a main sequence star. They even placed constraints on their respective masses before the explosion (4.6 and 17–20.5 solar masses, respectively).

After consulting images taken around the same time by another Snapshot program, they also noticed something interesting about SN 2017eaw. These images indicated that this supernova was especially luminous in the UV band (an “ultraviolet excess”). By combining these images with their data, Va Dyk and his team speculated that SN 2017eaw had an excess of light in the UV at the time it was observed, which was likely caused by interaction between the supernova shock and the circumstellar medium around that progenitor.

The team also noted that the dust created by a supernova explosion is a complicating factor due to how it cools as it expands outward. This dust, said Van Dyk, can obscure light from distant sources and lead to complications with the observations:

“The caveat here, then, is that the star that we saw pre-explosion might not be the progenitor at all, for instance and — again, because of the distances to the host galaxies — that star is within fractions of a pixel of the actual progenitor (physically, in the immediate neighborhood of the progenitor), such that, if the supernova has made dust, that dust is effectively blanketing both the supernova and that neighboring star. This is possible, but not inordinately likely. And it becomes a harder argument to make in those few cases where nothing is seen at the supernova position years later — as we point out in the paper, that would require enormous amounts of dust, which is likely physically not possible.”

Tracing the origins of supernovae is one of the many ways astronomers can learn more about the life cycle of stars. With improved instruments, data collection, and flexibility, they are able to reveal more about how our Universe evolved and will continue to change over time.

Further Reading: arXiv

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Clamshells Face the Acid Test

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It’s low tide in Bodega Bay, north of San Francisco, California, and Hannah Hensel is squishing through thick mud, on the hunt for clams. The hinged mollusks are everywhere, burrowed into the sediment, filtering seawater to feed on plankton. But Hensel isn’t looking for living bivalves—she’s searching the mudflat for the shells of dead clams.

“I did lose a boot or two,” she recalls. “You can get sunk into it pretty deep.”

Hensel, a doctoral candidate at the University of California, Davis, is studying shells, which are composed of acid-buffering calcium carbonate, as a tool that could one day help shelled species survive in the world’s rapidly acidifying oceans.

The inspiration for Hensel’s research comes from Indigenous sea gardening practices. On beaches from Alaska to Washington State, First Nations and tribal communities built rock-walled terraces in the intertidal zone to bolster populations of shellfish and other invertebrates. Although these sea gardens have not been documented farther south, clams were also vital sustenance in central California. Coast Miwok and Southern Pomo people harvested clams for food and shaped shells into bead money, says Tsim Schneider, an archaeologist at the University of California, Santa Cruz, and a member of the Federated Indians of Graton Rancheria. “So taking care of your clam beds was actually kind of protecting your vault, your bank,” says Schneider.

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In the sea gardens of the Pacific Northwest, caretakers crushed the shells of harvested clams and mixed the fragments back into the beach. Recent research has shown multiple positive effects of this broken shell “hash,” from opening spaces in the sediment so young clams can more easily burrow and grow, to releasing chemical cues that encourage larval clams to settle nearby.

This millennia-old practice may hold the key to addressing a new crisis. As humans burn fossil fuels, oceans are absorbing carbon dioxide from the atmosphere, making seawater more acidic. At lower pH levels, clams and other shellfish struggle to build shells. As their protective structures weaken and dissolve, the animals become vulnerable to damage and predation. But studies suggest that adding shell fragments to clam beds could release carbonate into the water, potentially neutralizing acidity caused by the greenhouse gas.

To find out whether shell hash could help California’s clams survive increasingly acidic conditions, Hensel brought shells from the tidal flat back to the lab, where she crushed them with a mortar and pestle and mixed the fragments into four plastic buckets of sand. Hensel filled these buckets, and four others containing sand alone, with local seawater and added the pinky nail–sized progeny of Pacific littleneck clams collected from Bodega Bay. She bubbled carbon dioxide through the seawater in half of the buckets to increase acidity. With their delicate shells, young clams are thought to be especially vulnerable to acidification.

In the lab, Hannah Hensel bubbles carbon dioxide through the seawater in experimental clam beds to test whether mixing crushed shells into the sediment can protect young Pacific littleneck clams from acidic conditions. Photos courtesy of Hannah Hensel

After 90 days, Hensel dug up all the clams. Comparing the buckets containing more acidic seawater, she observed that the bivalves burrowed in shell hash had grown bigger than the clams in sand alone. Strangely, though, the larger clams were not heavier, and Hensel plans to cross-section the shells to assess whether the new growth was thinner or less dense.

The results inform researchers that shell hash does have a buffering effect under certain conditions, says Leah Bendell, a marine ecologist at Simon Fraser University in British Columbia, who was not involved in the study. “It was a well-done lab experiment.”

Bendell also studies the buffering power of shell hash. Working with the Tsleil-Waututh Nation, Bendell and graduate student Bridget Doyle added shell fragments to clam beds in Burrard Inlet, near Vancouver, British Columbia. In that study, hash reduced pH fluctuations in seawater seeping through the sediment, which can vary markedly with rising and falling tides. Although the reduction was limited to areas with coarse sediments, and the hash did not reduce the overall pH, Bendell sees the results as a hint of something promising. Given a longer period of time, shell hash could have a greater effect on pH in certain clam beds, she says.

Shell hash may not be a panacea for ocean acidification everywhere, but Bendell and Hensel are slowly piecing together how carbonate might help individual beaches weather caustic conditions. Next summer, when Hensel begins adding shell hash to Bodega Bay’s clam beds, she will incorporate another element of traditional sea gardening. Indigenous caretakers regularly tilled clam beds, loosening the sediment and mixing in shell fragments. This repeated digging could bring oxygen to burrowed clams, open more space in the sediments, and alter seawater chemistry, Hensel says, and she plans to measure how the physical process affects both seawater chemistry and clam growth.

Schneider is hopeful that Hensel’s work will improve the health of his community’s clam beds, and the two researchers are discussing ways to involve the Indigenous communities around Bodega Bay. “I think it would just be really rewarding to see community members from my tribe having opportunities to be back out on the landscape to interact with traditional resources in the ways that our ancestors did,” Schneider says.

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