The next generation of dark matter detectors has arrived.
A massive new effort to detect the elusive substance has reported its first results. Following a time-honored tradition of dark matter hunters, the experiment, called LZ, didn’t find dark matter. But it has done that better than ever before, physicists report July 7 in a virtual webinar and a paper posted on LZ’s website. And with several additional years of data-taking planned from LZ and other experiments like it, physicists are hopeful they’ll finally get a glimpse of dark matter. “Dark matter remains one of the biggest mysteries in particle physics today,” LZ spokesperson Hugh Lippincott, a physicist at the University of California, Santa Barbara said during the webinar.
LZ, or LUX-ZEPLIN, aims to discover the unidentified particles that are thought to make up most of the universe’s matter. Although no one has ever conclusively detected a particle of dark matter, its influence on the universe can be seen in the motions of stars and galaxies, and via other cosmic observations (SN: 7/24/18).
Located about 1.5 kilometers underground at the Sanford Underground Research Facility in Lead, S.D., the detector is filled with 10 metric tons of liquid xenon. If dark matter particles crash into the nuclei of any of those xenon atoms, they would produce flashes of light that the detector would pick up.
The LZ experiment is one of a new generation of bigger, badder dark matter detectors based on liquid xenon, which also includes XENONnT in Gran Sasso National Laboratory in Italy and PandaX-4T in the China Jinping Underground Laboratory. The experiments aim to detect a theorized type of dark matter called Weakly Interacting Massive Particles, or WIMPs (SN: 12/13/16). Scientists scaled up the search to allow for a better chance of spying the particles, with each detector containing multiple tons of liquid xenon.
Using only about 60 days’ worth of data, LZ has already surpassed earlier efforts to pin down WIMPs (SN: 5/28/18). “It’s really impressive what they’ve been able to pull off; it’s a technological marvel,” says theoretical physicist Dan Hooper of Fermilab in Batavia, Ill, who was not involved with the study.
Although LZ’s search came up empty, “the way something’s going to be discovered is when you have multiple years in a row of running,” says LZ collaborator Matthew Szydagis, a physicist at the University at Albany in New York. LZ is expected to run for about five years, and data from that extended period may provide physicists’ best chance to find the particles.
Now that the detector has proven its potential, says LZ physicist Kevin Lesko of Lawrence Berkeley National Laboratory in California, “we’re excited about what we’re going to see.”
Tyrannosaurus rex’s tiny arms have launched a thousand sarcastic memes: I love you this much; can you pass the salt?; row, row, row your … oh.
But back off, snarky jokesters. A newfound species of big-headed carnivorous dinosaur with tiny forelimbs suggests those arms weren’t just an evolutionary punchline. Arm reduction — alongside giant heads — evolved independently in different dinosaur lineages, researchers report July 7 in Current Biology.
Meraxes gigas, named for a dragon in George R. R. Martin’s “A Song of Ice and Fire” book series, lived between 100 million and 90 million years ago in what’s now Argentina, says Juan Canale, a paleontologist with the country’s CONICET research network who is based in Buenos Aires. Despite the resemblance to T. rex, M. gigas wasn’t a tyrannosaur; it was a carcharodontosaur — a member of a distantly related, lesser-known group of predatory theropod dinosaurs. M. gigas went extinct nearly 20 million years before T. rex walked on Earth. The M. gigas individual described by Canale and colleagues was about 45 years old and weighed more than four metric tons when it died, they estimate. The fossilized specimen is about 11 meters long, and its skull is heavily ornamented with crests and bumps and tiny hornlets, ornamentations that probably helped attract mates.
Why these dinosaurs had such tiny arms is an enduring mystery. They weren’t for hunting: Both T. rex and M. gigas used their massive heads to hunt prey (SN: 10/22/18). The arms may have shrunk so they were out of the way during the frenzy of group feeding on carcasses.
But, Canale says, M. gigas’ arms were surprisingly muscular, suggesting they were more than just an inconvenient limb. One possibility is that the arms helped lift the animal from a reclining to a standing position. Another is that they aided in mating — perhaps showing a mate some love.
Getting a COVID-19 test has become a regular part of many college students’ lives. That ritual may protect not just those students’ classmates and professors but also their municipal bus drivers, neighbors and other members of the local community, a new study suggests.
Counties where colleges and universities did COVID-19 testing saw fewer COVID-19 cases and deaths than ones with schools that did not do any testing in the fall of 2020, researchers report June 23 in PLOS Digital Health. While previous analyses have shown that counties with colleges that brought students back to campus had more COVID-19 cases than those that continued online instruction, this is the first look at the impact of campus testing on those communities on a national scale (SN: 2/23/21). “It’s tough to think of universities as just silos within cities; it’s just much more permeable than that,” says Brennan Klein, a network scientist at Northeastern University in Boston.
Colleges that tested their students generally did not see significantly lower case counts than schools that didn’t do testing, Klein and his colleagues found. But the communities surrounding these schools did see fewer cases and deaths. That’s because towns with colleges conducting regular testing had a more accurate sense of how much COVID-19 was circulating in their communities, Klein says, which allowed those towns to understand the risk level and put masking policies and other mitigation strategies in place.
The results highlight the crucial role testing can continue to play as students return to campus this fall, says Sam Scarpino, vice president of pathogen surveillance at the Rockefeller Foundation’s Pandemic Prevention Institute in Washington, D.C. Testing “may not be optional in the fall if we want to keep colleges and universities open safely,” he says. Finding a flight path As SARS-CoV-2, the virus that causes COVID-19 rapidly spread around the world in the spring of 2020, it had a swift impact on U.S. college students. Most were abruptly sent home from their dorm rooms, lecture halls, study abroad programs and even spring break outings to spend what would be the remainder of the semester online. And with the start of the fall semester just months away, schools were “flying blind” as to how to bring students back to campus safely, Klein says.
That fall, Klein, Scarpino and their collaborators began to put together a potential flight path for schools by collecting data from COVID-19 dashboards created by universities and the counties surrounding those schools to track cases. The researchers classified schools based on whether they had opted for entirely online learning or in-person teaching. They then divided the schools with in-person learning based on whether they did any testing.
It’s not a perfect comparison, Klein says, because this method groups schools that did one round of testing with those that did consistent surveillance testing. But the team’s analyses still generally show how colleges’ pandemic response impacted their local communities.
Overall, counties with colleges saw more cases and deaths than counties without schools. However, testing helped minimize the increase in cases and deaths. During the fall semester, from August to December, counties with colleges that did testing saw on average 14 fewer deaths per 100,000 people than counties with colleges that brought students back with no testing — 56 deaths per 100,000 versus about 70. The University of Massachusetts Amherst, with nearly 30,000 undergraduate and graduate students in 2020, is one case study of the value of the testing, Klein says. Throughout the fall semester, the school tested students twice a week. That meant that three times as many tests occurred in the city of Amherst than in neighboring cities, he says. For much of the fall and winter, Amherst had fewer COVID-19 cases per 1,000 residents than its neighboring counties and statewide averages.
Once students left for winter break, campus testing stopped – so overall local testing dropped. When students returned for spring semester in February 2021, area cases spiked — possibly driven by students bringing the coronavirus back from their travels and by being exposed to local residents whose cases may have been missed due to the drop in local testing. Students returned “to a town that has more COVID than they realize” Klein says.
Renewed campus testing not only picked up the spike but quickly prompted mitigation strategies. The university moved classes to Zoom and asked students to remain in their rooms, at one point even telling them that they should not go on walks outdoors. By mid-March, the university reduced the spread of cases on campus and the town once again had a lower COVID-19 case rate than its neighbors for the remainder of the semester, the team found.
The value of testing It’s helpful to know that testing overall helped protect local communities, says David Paltiel, a public health researcher at the Yale School of Public Health who was not involved with the study. Paltiel was one of the first researchers to call for routine testing on college campuses, regardless of whether students had symptoms.
“I believe that testing and masking and all those things probably were really useful, because in the fall of 2020 we didn’t have a vaccine yet,” he says. Quickly identifying cases and isolating affected students, he adds, was key at the time. But each school is unique, he says, and the benefit of testing probably varied between schools. And today, two and a half years into the pandemic, the cost-benefit calculation is different now that vaccines are widely available and schools are faced with newer variants of SARS-CoV-2. Some of those variants spread so quickly that even testing twice a week may not catch all cases on campus quickly enough to stop their spread, he says.
As colleges and universities prepare for the fall 2022 semester, he would recommend schools consider testing students as they return to campus with less frequent follow-up surveillance testing to “make sure things aren’t spinning crazy out of control.”
Still, the study shows that regular campus testing can benefit the broader community, Scarpino says. In fact, he hopes to capitalize on the interest in testing for COVID-19 to roll out more expansive public health testing for multiple respiratory viruses, including the flu, in places like college campuses. In addition to PCR tests — the kind that involve sticking a swab up your nose — such efforts might also analyze wastewater and air within buildings for pathogens (SN: 05/28/20).
Unchecked coronavirus transmission continues to disrupt lives — in the United States and globally — and new variants will continue to emerge, he says. “We need to be prepared for another surge of SARS-CoV-2 in the fall when the schools reopen, and we’re back in respiratory season.”
Emerald jewel wasps know what cockroach brains feel like.
This comes in handy when a female wasp needs to turn a cockroach into an obedient zombie that will host her larvae and serve as dinner. First, the wasp plunges its stinger into the cockroach’s midsection to briefly paralyze the legs. Next comes a more delicate operation: stinging the head to deliver a dose of venom to specific nerve cells in the brain, which gives the wasp control over where its victim goes. But how does a wasp know when it’s reached the brain? The stinger’s tip is a sensory probe. In experiments using brainless cockroaches, a wasp will sting the head over and over again, searching fruitlessly for its desired target.
A brain-feeling stinger is just one example of the myriad ways animals sense the world around them. We humans tend to think the world is as we perceive it. But for everything that we can see, smell, taste, hear or touch, there’s so much more that we’re oblivious to.
In An Immense World, science journalist Ed Yong introduces that hidden world and the concept of Umwelt, a German word that refers to the parts of the environment an animal senses and experiences. Every creature has its own Umwelt. In a room filled with different types of organisms, or even multiple people, each individual would experience that shared atmosphere in wholly different ways.
Yong eases readers into the truly immense world of senses by starting with ones that we are intimately familiar with. In some cases, he tests the limits of his own abilities. Dog noses, for instance, are better than human noses at sniffing out a scent long after the source is gone, as Yong demonstrates. While crawling around on his hands and knees with his eyes closed, he was able to track a chocolate-scented string that a researcher had put on the ground. But he lost the scent when the string was removed. That wouldn’t happen to a dog. It would pick up the trace, string or no string. In exploring the vast sensory world, it helps to have a good imagination, as even familiar senses can seem quite strange. Scallops, for instance, have eyes and somehow “see” despite having a crude brain that can’t process the images. Crickets have hairs that are so responsive to an approaching spider that trying to make the hairs more sensitive might break the rules of physics. A blind Ecuadorian catfish senses raging water with durable teeth that cover its skin. The animal uses the dentures to find calmer waters.
Going through these imagination warm-up exercises makes it somewhat easier to ponder what it might be like to be an echolocating bat, a bird that detects magnetic fields or a fish that communicates using electricity. Yong’s vivid descriptions also help readers fathom these senses: “A river full of electric fish must be like a cocktail party where no one ever shuts up, even when their mouths are full.” In a forest, foliage may seem largely silent, but some insects “talk” through plant stems using vibration. With headphones hooked up to plants so that scientists can listen in, “chirping cicadas sound like cows and katydids sound like revving chainsaws.”
For all the book’s wonder, the last chapter brings readers crashing back to today’s reality. Humans are polluting animals’ Umwelten; we’re forcing animals to exist in environments contaminated with human-made stimuli. And the consequences can be deadly, Yong warns. Adding artificial light in the darkness of night is killing birds and insects (SN: 8/31/21). Making environments louder is masking the sounds of predators and forcing prey to spend more time keeping an eye out than eating (SN: 5/4/17). “We are closer than ever to understanding what it is like to be another animal,” Yong writes, “but we have made it harder than ever for other animals to be.”
Since each of us has our own Umwelt, fully understanding the foreign worlds of animals is close to impossible, Yong writes. How do we know, for instance, which animals feel pain? Researchers can dissect the signals or stimuli an animal might receive. But what that creature experiences often remains a mystery.
In the quest to measure the fundamental constant that governs the strength of gravity, scientists are getting a wiggle on.
Using a pair of meter-long, vibrating metal beams, scientists have made a new measurement of “Big G,” also known as Newton’s gravitational constant, researchers report July 11 in Nature Physics. The technique could help physicists get a better handle on the poorly measured constant.
Big G is notoriously difficult to determine (SN: 9/12/13). Previous estimates of the constant disagree with one another, leaving scientists in a muddle over its true value. It is the least precisely known of the fundamental constants, a group of numbers that commonly show up in equations, making them a prime target for precise measurements. Because the vibrating beam test is a new type of experiment, “it might help to understand what’s really going on,” says engineer and physicist Jürg Dual of ETH Zurich.
The researchers repeatedly bent one of the beams back and forth and used lasers to measure how the second beam responded to the first beam’s varying gravitational pull. To help maintain a stable temperature and avoid external vibrations that could stymie the experiment, the researchers performed their work 80 meters underground, in what was once a military fortress in the Swiss Alps.
Big G, according to the new measurement, is approximately 6.82 x 10-11 meters cubed per kilogram per square second. But the estimate has an uncertainty of about 1.6 percent, which is large compared to other measurements (SN: 8/29/18). So the number is not yet precise enough to sway the debate over Big G’s value. But the team now plans to improve their measurement, for example by adding a modified version of the test with rotating bars. That might help cut down on Big G’s wiggle room.
Demond “Dom” Mullins’ days as a student at Lehman College in New York were interrupted in 2004 when his National Guard unit was deployed to Baghdad. A year later, he returned home but struggled with depression and rage. Immersing himself in his studies helped him make sense of the world and his experiences. After completing degrees in Africana studies and political science, Mullins earned a Ph.D. in sociology, focusing his research on a subject he knew firsthand: how returning veterans reintegrate into society.
In 2015, the avid climber and adventure sportsman joined six other veterans and a journalist on a monthlong excursion to climb Alaska’s Denali, the highest peak in North America. To understand the health benefits of high-risk outdoor adventuring outside the clinical therapy framework, Mullins interviewed each participant and collected data about group cohesion and the impact of such high-risk activities on social bonds for his study “Veterans Expeditions: Tapping the great outdoors.”
Formerly an adjunct assistant professor at the Cooper Union for the Advancement of Science and Art in New York City, Mullins has climbed Kilimanjaro and Mount Kenya. In May, he tackled his biggest climbing challenge yet: summiting Mount Everest, the world’s tallest mountain. He and seven other members of Full Circle Everest, an all-Black mountaineering team, set out to make history. Seven of them reached the summit, coming very close to doubling the number of Black people who have achieved that feat. Science News asked Mullins, while he was preparing for the climb, about his research and why he wants more Black people in outdoor spaces. This interview was edited for clarity and length.
SN: When you returned home from Iraq, you cut yourself off from others and contemplated ending your life. What helped you get through the worst times?
Mullins: Education. I was grappling with the discontents of coming home and struggling with what I had experienced in the Iraq War. Education allowed me to explore aspects of my experience intellectually through things that really engaged me — history and social theory.
SN: Did the war change what you envisioned for yourself academically?
Mullins: It influenced my trajectory. Graduate school was not even on my radar before. When I came home, I had this great urgency to improve my future, learn more about global politics and understand how history could produce such a moment. I also wanted to know how all of that might influence veterans’ reintegration.
SN: How did the Denali research expedition follow on your work on veteran reintegration?
I became an avid mountaineer, rock and ice climber and began training with Veterans Expeditions [a nonprofit that works to enhance the life of U.S. veterans]. By the time the Denali expedition came about in May 2015, the cofounder [Nick Watson] asked me to be a part of it. I wanted to tell the story of veterans summiting Denali in a way that makes sense, was scientifically rigorous and could contribute to the research. I wanted to answer certain questions about how interventions like hiking and climbing might come into play. Ethnography [the study of people in their environment] was the best way to do that.
SN: What did you learn about veterans and outdoor adventuring?
Mullins: Much more than in the past, my generation of veterans is more willing to talk about their experiences with each other to find affinity and solidarity. After leaving the service, some lose their identity, partly because there is no space reserved for them to perform the identities they have cultivated through military training, socialization and performance. I learned that they engage in these kinds of high-risk sporting events to support their identities. The outdoors is sort of a theater to perform the heroic identities they’ve developed in a way that can be conducive to greater physical and communal health. One veteran said to me, “The rock and the ice don’t lie to me.” He was reasserting that he is a warrior. SN: How did you become a part of Full Circle Everest?
Mullins: Through Veterans Expeditions, I developed a relationship with [world-famous mountaineer] Conrad Anker. Conrad had this idea about putting together an all-Black expedition to Everest. He introduced me to [Full Circle expedition leader and organizer] Philip Henderson, who had been considering this for a long time. I met Phil and knew right away that I wanted to be a part of that expedition and help find other athletes.
SN: What, if anything, about your experience on Denali do you believe will benefit your attempt to summit Mount Everest?
Mullins: Everest is 9,000 feet taller than Denali. It’s a longer pursuit and a longer expedition, but the conditions will be similar. We got snowed in on Denali for 17 days, which I believe has prepared me for my expedition with Full Circle.
This pursuit is about developing relationships with people who have common experiences. It’s having someone who gets your drift, who understands what you mean without you needing to explain everything. It’s about building community and feeling like you belong. People want to feel like the group is better as a result of their participation. It’s all about social cohesion.
SN: Will you be conducting research on this expedition?
Mullins: This time, I’ll be studying myself — doing an autoethnography. I took time off from work to do this climb, so I don’t have any pressing job to get back to. I plan to take some time to reflect and write about this once it’s over, to help people understand the value of it for me. SN: The Full Circle team spent a few weeks together in January at the Khumbu Climbing Center in Nepal. Your teammates went home, then came back in April to start the climb, but you stayed in Nepal. Why?
Mullins: It gives me an edge in so many different ways: having time for my body to properly acclimate to the elevation, understanding how to keep myself safe and comfortable in the elements. Also developing relationships with the locals, the Sherpas and the other Nepalese persons who are supporting the expedition.
SN: What do you want people to take away from your Full Circle Everest expedition?
Mullins: Diversity in the outdoors matters. The military completely introduced me to outdoor sports. When I was a kid, I never went camping or even hiking. I thought [Brooklyn’s] Prospect Park was the wilderness. These activities have benefits for all people. Hopefully, Full Circle will help African Americans of all ages get outside to hike, camp and explore.
Some mosquito-borne viruses turn mice into alluring mosquito bait.
Mice infected with dengue or Zika viruses — and people infected with dengue — emit a flowery, orange-smelling chemical that tempts hungry mosquitoes, researchers report June 30 in Cell. In mice, the infections spur the growth of skin-inhabiting bacteria that make the chemical, drawing in bloodsucking Aedes aegypti mosquitoes that could then transmit the viruses to new hosts, including humans.
Previous studies showed that other mosquito species prefer to feed on animals carrying the parasite that causes malaria (SN: 2/9/17). But it was unknown whether the same was true for viruses such as dengue or Zika, says Gong Cheng, a microbiologist at Tsinghua University in Beijing.
The chemical acetophenone — which to humans smells like orange blossom — may be that lure. Mice infected with dengue or Zika viruses give off approximately 10 times more acetophenone and attract more mosquitoes than uninfected animals, Cheng and colleagues found. People infected with dengue similarly release more of the chemical than healthy people. Samples of odors taken from the armpits of infected people also created potent mosquito magnets when smeared on filter paper attached to a volunteer’s palm. Acetophenone typically comes from bacteria. Researchers found that Bacillus bacteria on mice were the likely culprits producing the chemical. An infection stops mice from making an antimicrobial protein called RELMα, allowing the acetophenone-emitting microbes to flourish.
But a component of some acne medications can bring back RELMα in mice, the team found. Infected animals fed a derivative of vitamin A called isotretinoin produced less acetophenone and become less attractive mosquito targets.
It’s possible that giving people isotretinoin could help reduce virus transmission among people by hiding infected people from the bloodsucking insects, Cheng says. He and colleagues are planning to test the strategy in Malaysia, where dengue circulates.
We’ve now seen farther, deeper and more clearly into space than ever before.
A stellar birthplace, a nebula surrounding a dying star, a group of closely interacting galaxies, the first spectrum of an exoplanet’s light. These are some of the first images from the James Webb Space Telescope, released in a NASA news briefing on July 12. This quartet of cosmic scenes follows on the heels of the very first image released from the telescope, a vista of thousands of distant galaxies, presented in a White House briefing on July 11. “First of all, it’s really gorgeous. And it’s teeming with galaxies,” said JWST Operations Scientist Jane Rigby at the July 12 briefing. “That’s been true of every image we’ve taken with Webb. We can’t take [an image of] blank sky. Everywhere we look, there’s galaxies everywhere.”
Going deep The galaxies captured in the first released image lie behind a cluster of galaxies about 4.6 billion light-years away. The mass from those closer galaxies distorts spacetime in such a way that objects behind the cluster are magnified, giving astronomers a way to peer more than 13 billion years into the early universe.
Even with that celestial assist, other existing telescopes could never see so far. But the James Webb Space Telescope, also known as JWST, is incredibly large — at 6.5 meters across, its mirror is nearly three times as wide as that of the Hubble Space Telescope. It also sees in the infrared wavelengths of light where distant galaxies appear. Those features give it an edge over previous observatories.
“There’s a sharpness and a clarity we’ve never had,” said Rigby, of NASA’s Goddard Space Flight Center in Greenbelt, Md. “You can really zoom in and play around.” Although that first image represents the deepest view of the cosmos to date, “this is not a record that will stand for very long,” astronomer Klaus Pontoppidan of the Space Telescope Science Institute in Baltimore said in a June 29 news briefing. “Scientists will very quickly beat that record and go even deeper.”
But JWST wasn’t built only to peer deeper and farther back in time than ever before. The cache of first images and data showcases space scenes both near and far, glimpses of single stars and entire galaxies, and even a peek into the chemical composition of a far-off planet’s atmosphere.
“These are pictures just taken over a period of five days. Every five days, we’re getting more data,” European Space Agency science advisor Mark McCaughrean said at the July 12 briefing. (JWST is an international collaboration among NASA, ESA and the Canadian Space Agency.) “It’s a culmination of decades of work, but it’s just the beginning of decades. What we’ve seen today with these images is essentially that we’re ready now.” Cosmic cliffs This image shows the “Cosmic Cliffs,” part of the enormous Carina nebula, a region about 7,600 light-years from Earth where many massive stars are being born. Some of the most famous Hubble Space Telescope images feature this nebula in visible light, but JWST shows it in “infrared fireworks,” Pontoppidan says. JWST’s infrared detectors can see through dust, so the nebula appears especially spangled with stars. “We’re seeing brand new stars that were previously completely hidden from our view,” said NASA Goddard astrophysicist Amber Straughn.
But molecules in the dust itself are glowing too. Energetic winds from baby stars in the top of the image are pushing and sculpting the wall of gas and dust that runs across the middle. “We see examples of bubbles and cavities and jets that are being blown out from newborn stars,” Straughn said. And gas and dust are the raw material for new stars — and new planets.
“It reminds me that our sun and our planets, and ultimately us, were formed out of this same stuff that we see here,” Straughn said. “We humans really are connected to the universe. We’re made out of the same stuff.” Foamy nebula The Southern Ring nebula is an expanding cloud of gas that surrounds a dying star about 2,000 light-years from Earth. In previous Hubble images, the nebula looks like an oblong swimming pool with a fuzzy orange deck and a bright diamond, a white dwarf star, in the middle. JWST expands the view far beyond that, showing more tendrils and structures in the gas than previous telescopes could see. “You see this bubbly, almost foamy appearance,” said JWST astronomer Karl Gordon, of the Space Telescope Science Institute. In the left hand image, which captures near-infrared light from JWST’s NIRCam instrument, the foaminess traces molecular hydrogen that formed as dust expanded away from the center. The center appears blue due to hot ionized gas heated by the leftover core of the star. Rays of light escape the nebula like the sun peeking through patchy clouds.
In the right-hand image, taken by the MIRI mid-infrared camera, the outer rings look blue and trace hydrocarbons forming on the surface of dust grains. The MIRI image also reveals a second star in the nebula’s core.
“We knew this was a binary star, but we didn’t see much of the actual star that produced this nebula,” Gordon said. “Now in MIRI this star glows red.” A galactic quintet Stephan’s Quintet is a group of galaxies about 290 million light-years away that was discovered in 1877. Four of the galaxies are engaged in an intimate gravitational dance, with one member of the group passing through the core of the cluster. (The fifth galaxy is actually much closer to Earth and just appears in a similar spot on the sky.) JWST’s images show off more structure within the galaxies than previous observations did, revealing where stars are being born.
“This is a very important image and area to study,” because it shows the sort of interactions that drive the evolution of galaxies, said JWST scientist Giovanna Giardino of the European Space Agency.
In an image from the MIRI instrument alone, the galaxies look like wispy skeletons reaching towards each other. Two galaxies are clearly close to merging. And in the top galaxy, evidence of a supermassive black hole comes to light. Material swirling around the black hole is heated to extremely high temperatures and glows in infrared light as it falls into the black hole. An exoplanet’s sky This “image” is clearly different from the others, but it’s no less scientifically exciting. It shows the spectrum of light from the star WASP 96 as it passes through the atmosphere of its gas giant planet, WASP 96b.
“You get a bunch of what looks like bumps and wiggles to some people but it’s actually full of information content,” said NASA exoplanet scientist Knicole Colón. “You’re actually seeing bumps and wiggles that indicate the presence of water vapor in the atmosphere of this exoplanet.” The planet is about half the mass of Jupiter and orbits its star every 3.4 days. Previously astronomers thought it had no clouds in its sky, but the new data from JWST show signs of clouds and haze. “There is evidence of clouds and hazes because the water features are not quite as large as we predicted,” Colón said. A long time coming These first images and data have been a very long time coming. The telescope that would become JWST was first dreamed up in the 1980s, and the planning and construction suffered years of budget issues and delays (SN: 10/6/21).
The telescope finally launched on December 25. It then had to unfold and assemble itself in space, travel to a gravitationally stable spot about 1.5 million kilometers from Earth, align its insectlike primary mirror made of 18 hexagonal segments and calibrate its science instruments (SN: 1/24/22). There were hundreds of possible points of failure in that process, but the telescope unfurled successfully and got to work.
“We are so thrilled that it works because there’s so much at risk,” says JWST senior project scientist John Mather of NASA’s Goddard Space Flight Center. “The world has trusted us to put our billions into this and make it go, and it works. So it’s an immense relief.” In the months following, the telescope team released teasers of imagery from calibration, which already showed hundreds of distant, never-before-seen galaxies. But the images now being released are the first full-color pictures made from the data scientists will use to start unraveling mysteries of the universe.
“It sees things that I never dreamed were out there,” Mather says.
For the telescope team, the relief in finally seeing the first images was palpable. “It was like, ‘Oh my god, we made it!’” says image processor Alyssa Pagan, also of Space Telescope Science Institute. “It seems impossible. It’s like the impossible happened.”
In light of the expected anticipation surrounding the first batch of images, the imaging team was sworn to secrecy. “I couldn’t even share it with my wife,” says Pontoppidan, leader of the team that produced the first color science images.
“You’re looking at the deepest image of the universe yet, and you’re the only one who’s seen that,” he says, of the first picture released July 11. “It’s profoundly lonely.” Soon, though, the team of scientists, image processors and science writers was seeing something new every day for weeks as the telescope downloaded the first images. “It’s a crazy experience,” Pontoppidan says. “Once in a lifetime.”
For Pagan, the timing is perfect. “It’s a very unifying thing,” she says. “The world is so polarized right now. I think it could use something that’s a little bit more universal and connecting. It’s a good perspective, to be reminded that we’re part of something so much greater and beautiful.”
JWST is just getting started as it now begins its first round of full science operations. “There’s lots more science to be done,” Mather says. “The mysteries of the universe will not come to an end anytime soon.”
There is a galaxy spinning like a record in the early universe — far earlier than any others have been seen twirling around.
Astronomers have spotted signs of rotation in the galaxy MACS1149-JD1, JD1 for short, which sits so far away that its light takes 13.3 billion years to reach Earth. “The galaxy we analyzed, JD1, is the most distant example of a rotational galaxy,” says astronomer Akio Inoue of Waseda University in Tokyo. “The origin of the rotational motion in galaxies is closely related to a question: how galaxies like the Milky Way formed,” Inoue says. “So, it is interesting to find the onset of rotation in the early universe.”
JD1 was discovered in 2012. Due to its great distance from Earth, its light had been stretched, or redshifted, into longer wavelengths, thanks to the expansion of the universe. That redshifted light revealed that JD1 existed just 500 million years after the Big Bang.
Astronomers used light from the entire galaxy to make that measurement. Now, using the Atacama Large Millimeter/submillimeter Array in Chile for about two months in 2018, Inoue and colleagues have measured more subtle differences in how that light is shifted across the galaxy’s disk. The new data show that, while all of JD1 is moving away from Earth, its northern part is moving away slower than the southern part. That’s a sign of rotation, the researchers report in the July 1 Astrophysical Journal Letters.
JD1 spins at about 180,000 kilometers per hour, roughly a quarter the spin speed of the Milky Way. The galaxy is also smaller than modern spiral galaxies. So JD1 may be just starting to spin, Inoue says.
The James Webb Space Telescope will observe JD1 in the next year to reveal more clues to how that galaxy, and others like ours, formed (SN: 10/6/21).
No beast on Earth is tougher than the tiny tardigrade. It can survive being frozen at -272° Celsius, being exposed to the vacuum of outer space and even being blasted with 500 times the dose of X-rays that would kill a human.
In other words, the creature can endure conditions that don’t even exist on Earth. This otherworldly resilience, combined with their endearing looks, has made tardigrades a favorite of animal lovers. But beyond that, researchers are looking to the microscopic animals, about the size of a dust mite, to learn how to prepare humans and crops to handle the rigors of space travel. The tardigrade’s indestructibility stems from its adaptations to its environment — which may seem surprising, since it lives in seemingly cushy places, like the cool, wet clumps of moss that dot a garden wall. In homage to such habitats, along with a pudgy appearance, some people call tardigrades water bears or, adorably, moss piglets.
But it turns out that a tardigrade’s damp, mossy home can dry out many times each year. Drying is pretty catastrophic for most living things. It damages cells in some of the same ways that freezing, vacuum and radiation do.
For one thing, drying leads to high levels of peroxides and other reactive oxygen species. These toxic molecules chisel a cell’s DNA into short fragments — just as radiation does. Drying also causes cell membranes to wrinkle and crack. And it can lead delicate proteins to unfold, rendering them as useless as crumpled paper airplanes. Tardigrades have evolved special strategies for dealing with these kinds of damage. As a tardigrade dries out, its cells gush out several strange proteins that are unlike anything found in other animals. In water, the proteins are floppy and shapeless. But as water disappears, the proteins self-assemble into long, crisscrossing fibers that fill the cell’s interior. Like Styrofoam packing peanuts, the fibers support the cell’s membranes and proteins, preventing them from breaking or unfolding.
At least two species of tardigrade also produce another protein found in no other animal on Earth. This protein, dubbed Dsup, short for “damage suppressor,” binds to DNA and may physically shield it from reactive forms of oxygen.
Emulating tardigrades could one day help humans colonize outer space. Food crops, yeast and insects could be engineered to produce tardigrade proteins, allowing these organisms to grow more efficiently on spacecraft where levels of radiation are elevated compared with on Earth.
Scientists have already inserted the gene for the Dsup protein into human cells in the lab. Many of those modified cells survived levels of X-rays or peroxide chemicals that kill ordinary cells (SN: 11/9/19, p. 13). And when inserted into tobacco plants — an experimental model for food crops — the gene for Dsup seemed to protect the plants from exposure to a DNA-damaging chemical called ethyl methanesulfonate. Plants with the extra gene grew more quickly than those without it. Plants with Dsup also incurred less DNA damage when exposed to ultraviolet radiation. Tardigrades’ “packing peanut” proteins show early signs of being protective for humans. When modified to produce those proteins, human cells became resistant to camptothecin, a cell-killing chemotherapy agent, researchers reported in the March 18 ACS Synthetic Biology. The tardigrade proteins did this by inhibiting apoptosis, a cellular self-destruct program that is often triggered by exposure to harmful chemicals or radiation.
So if humans ever succeed in reaching the stars, they may accomplish this feat, in part, by standing on the shoulders of the tiny eight-legged endurance specialists in your backyard.