New technique shows old temperatures were much hotter than thought - Ars Technica

Enlarge / Isotopes in sediment cores like these can provide indications of past temperatures.

E Alaska Scientific Party

In a paper recently published in Science, Professor Nele Meckler of the University of Bergen and colleagues argue that the climate between around 35 and 60 million years ago may have been considerably warmer than we thought. Their finding suggests that a given level of CO₂ might produce more warming than prior work indicated, and it hints that the ocean circulated differently during that warm, ice-free climate.

Their conclusions come from new measurements of carbon and oxygen isotopes found in the shells of tiny creatures, called benthic foraminifera or “forams,” that lived on the seafloor at the time. Earlier work with similar samples had estimated temperatures using oxygen isotopes—a technique that could be confused by changes in how much water was locked away in ice at the poles and, to a lesser extent, variations in ocean salinity. The new study used a technique that registers temperatures more reliably and produced much warmer numbers.

A newer, clearer thermometer

Benthic foram oxygen isotopes have been a mainstay of ancient global climate studies, with the latest most detailed record extending back 60 million years. Deep ocean temperatures reflect ocean surface temperatures over timescales longer than about 1,000 years because the global “conveyor belt” of ocean circulation turns over on that timescale. Oxygen isotopes in that water reflect ocean surface temperature, and by extension global climate, because water with the heavier isotope oxygen-18 is a bit harder to evaporate than water with oxygen-16; when the sea is warmer and there’s more evaporation, oxygen-18 builds up in the oceans.

This isotope buildup is calibrated to temperature, but that calibration requires knowing ocean salinity and how much water is locked up in ice caps. “The global [oxygen isotope] curve… has always had this semi-hidden uncertainty due to the dual influences of temperature and ice volume that we can now resolve using clumped isotopes,” said Sierra Petersen of the University of Michigan, who was not involved in Meckler’s study.

The clumped isotope method removes the need to make that assumption about how much water is locked away in ice because it simultaneously measures the levels of carbon-13 found in the same sample of calcium carbonate in a foram shell. Thermodynamics favors “clumping” of heavier isotopes in calcium carbonate in cold water, but as the water gets warmer, entropy increasingly exerts its influence, and the heavier isotopes become more scattered in the shell material. The degree of isotope clumping is calibrated to temperature in the lab for a variety of materials, enabling clumped isotope measurements to yield temperature measurements in deep time.

The new method indicates that between 57 and 52 million years ago, the North Atlantic abyss was about 20°C. That’s a big difference from the oxygen isotope data, which yielded temperatures of 12–14°C. “That's a whole lot warmer,” said Meckler. For comparison, today’s equivalent is around 1–2°C.

A hotter greenhouse?

Comparing these new temperatures to the CO₂ levels prevalent at the time produced a bit of a surprise. “Perhaps most striking is the evidence this study provides for tight coupling between geologically brief periods of high CO₂ and deep ocean temperature,” said John Eiler of Caltech, who pioneered the use of clumped isotopes to measure ancient temperatures but was not part of Meckler’s study.

The Intergovernmental Panel on Climate Change's best estimate is that doubling our CO₂ from preindustrial levels will result in 3°C of global warming, but the uncertainty remains large—it could be between 2.5°C and 4°C for that same increase in CO₂. If the value is closer to 4ºC, Earth will warm more for the same amount of CO₂ in the air.

Meckler’s warmer temperatures suggest that CO₂’s capacity to warm during that time in Earth’s past was higher than was found in earlier studies. “This would lead to a higher climate sensitivity to atmospheric CO₂,” the paper says.

Alternatively, reconstructions of atmospheric CO₂ levels at the time may underestimate those past gas concentrations. “There's quite a lot of uncertainty still in the CO₂ reconstructions,” Meckler said. She also noted that the researchers don’t yet have global coverage with their data.

“I do want to want to put a caveat here that we have only looked at the Atlantic Ocean so far, so it could be that the Atlantic Ocean is doing something special,” Meckler told Ars. “This increased sensitivity to CO₂ would only be the case if this was really a global signal—we don't know that yet.”

Signs of weird ocean circulation

Meckler’s team also uncovered large, multi-million-year swings in ocean-bottom temperature.

They found surprisingly cool temperatures 55 million years ago, sandwiched between super-warm temperatures 57 and 52 million years ago. Meckler told Ars she was “very puzzled” by such large temperature swings, with cool temperatures showing up shortly after a well-known global warming event called the “Paleocene Eocene Thermal Maximum” or “PETM.” The PETM occurred 56 million years ago; unfortunately, the team does not have data covering the PETM itself.

The fact that these 7–8°C temperature swings are not seen in the oxygen isotope data suggests that both temperature and salinity were changing—a hint that ocean currents may have reorganized at the time. This is because exchanging warm salty water with cooler, fresher water causes the salinity to cancel out the temperature signal in the oxygen isotope data, but not in the new clumped isotope data. This would explain why the temperature swings appear in just one of the methods.

“There could be changes in the connectivity between the North Atlantic and the Arctic for tectonic reasons,” Meckler said. “I'm wondering if there's kind of switches between a more high-latitude colder and fresh water mass and a lower latitude warmer and saline water mass.”

A tectonic cause makes sense since the Arctic Ocean was much more cut off from the global ocean and less salty then, and a plume of hot rock beneath Earth’s crust affected seabed topography in the North Atlantic at the time. But it could also be that global ocean circulation operated differently due to the hot climate. “During those conditions where you have greenhouse climates, you don't have ice sheets, and you have… more intense hydrological cycles,” Meckler told Ars, “so the system might be operating quite differently under those conditions.”

As scientists reach further and further back in time for climates that can inform us about our own future, figuring out how the oceans behaved at those times becomes ever more important. “If you can have these big changes in ocean circulation, that is something we need to understand,” said Meckler. “What does that mean for how… the climate system reacts to changes in tectonics but also changes in CO₂?”

Eiler highlighted that aspect of the study, saying, “This is a highly significant study that both advances our understanding of the deep ocean during periods of sustained globally warm climate and challenges longstanding interpretations of the temperature structure of the oceans during 'greenhouse' eras.”

Meckler’s team is already working on adding detail to their currently sparse temperature record, something that other scientists eagerly anticipate. “I hope that this excellent work can be reproduced across multiple ocean basins to identify previously hidden patterns of changing [seawater oxygen isotopes] and temperature through space and time,” said Petersen.

Science, 2022. DOI: 10.1126/science.abk0604

Howard Lee is a freelance science writer focusing on geology and climate change in deep time. He holds a B.Sc. in geology and M.Sc. in remote sensing, both from the University of London, UK.

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NASA taps SpaceX for 5 more astronaut missions worth $1.4 billion - CNBC

The SpaceX Falcon 9 rocket, carrying astronauts Doug Hurley and Bob Behnken in the Crew Dragon capsule, lifts off from Kennedy Space Center, Fla., on Saturday, May 30, 2020. The SpaceX Demo-2 mission is the first crewed launch of an orbital spaceflight from the U.S. in nearly a decade.

Joe Burbank | Orlando Sentinel | Getty Images

NASA on Wednesday announced it has awarded five more astronaut missions to Elon Musk's SpaceX, with a contract worth an additional $1.4 billion to the company.

The extra flights fall under NASA's Commercial Crew program, which delivers astronauts and cargo to and from the International Space Station. SpaceX is currently on its fourth operational human spaceflight for the agency.

SpaceX's Crew Dragon spacecraft has been competing with Boeing and its Starliner capsule for contracts under Commercial Crew. While both companies have now been awarded nearly $5 billion to develop and launch their respective capsules, SpaceX has won 14 missions and Boeing has garnered six. The latter has yet to launch astronauts with Starliner.

Due in part to the fixed-price nature of NASA's contracts for the program, Boeing has absorbed $688 million in costs from delays and additional work on the capsule. After successfully completing an uncrewed Starliner flight to the ISS in May, the company now aims to carry astronauts for the first time in February.

The 20 flights awarded to date cover crew missions until 2030 when the ISS is expected to be retired from use.

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To Prevent a Martian Plague, NASA Needs to Build a Very Special Lab - The New York Times

When Carl Sagan imagined sending humans to Mars in his book “The Cosmic Connection,” published in 1973, he posed a problem beyond such a mission’s cost and complexity: the possibility that life already existed on the red planet and that it might not play nice.

“It is possible that on Mars there are pathogens,” he wrote, “organisms which, if transported to the terrestrial environment, might do enormous biological damage — a Martian plague.”

Michael Crichton imagined a related scenario in his novel “The Andromeda Strain.”

Such situations, in which extraterrestrial samples contain dangerous tagalong organisms, are examples of backward contamination, or the risk of material from other worlds harming Earth’s biosphere.

“The likelihood that such pathogens exist is probably small,” Sagan wrote, “but we cannot take even a small risk with a billion lives.”

Scientists have long considered Sagan’s warnings in mostly hypothetical terms. But over the approaching decade, they will start to act concretely on backward contamination risks. NASA and the European Space Agency are gearing up for a shared mission called Mars Sample Return. A rover on the red planet is currently scooping up material that will be collected by other spacecraft and eventually returned to Earth.

No one can say for sure that such material will not contain tiny Martians. If it does, no one can yet say for sure they are not harmful to Earthlings.

With such concerns in mind, NASA must act as if samples from Mars could spawn the next pandemic. “Because it is not a zero-percent chance, we are doing our due diligence to make sure that there’s no possibility of contamination,” said Andrea Harrington, the Mars sample curator for NASA. Thus, the agency plans to handle the returned samples similarly to how the Centers for Disease Control and Prevention handles ebola: carefully.

“Carefully,” in this case, means that once the Mars samples drop to Earth, they must be initially held in a structure called the Sample Receiving Facility. The mission’s planners say the structure should meet a standard known as “Biosafety Level 4,” or BSL-4, which means it is capable of safely containing the most dangerous pathogens known to science. But it also has to be pristine: functionally, a giant cleanroom that prevents substances on Earth from contaminating the samples from Mars.

The agency has little time to waste: If the sample return mission occurs on time — admittedly a big “if” — Mars rocks could land on Earth by the mid 2030s. It could take about as much time to build a facility that can safely contain the Martian materials, and that is if it is built on schedule, without disruption from political or public challenges.

Because no existing lab was both contained and clean enough for NASA, four scientists, including Dr. Harrington, went on a tour of some of the planet’s most dangerous facilities. She was joined by three colleagues, and they called themselves “NASA Tiger Team RAMA.” While this moniker sounds like the name of a military scouting party, it is an acronym out of the first names of the team members — Richard Mattingly of NASA’s Jet Propulsion Laboratory; Andrea Harrington; Michael Calaway, a contractor for the Johnson Space Center; and Alvin Smith, also of the Jet Propulsion Laboratory.

The group visited hot spots like the National Emerging Infectious Diseases Laboratories in Boston, the U.S. Army Medical Research Institute of Infectious Diseases at Fort Detrick in Maryland, and the Centers for Disease Control and Prevention’s ominously and vaguely named Building 18 in Atlanta.

In total, the team visited 18 facilities that handled biological horrors, maintain ultra-cleanrooms or manufacture innovative equipment for either purpose. Members hoped to figure out what has worked at existing labs and what a NASA facility could appropriate or optimize to keep humanity safe.

To scientists like Dr. Harrington, the hurry and hurdles are worth it. “This will be the first sample return mission from another planet,” she said. The first time another world has met humans, in other words, because humans introduced them.

🪨🔴🚀

Annie Mulligan for The New York Times

Materials from around the solar system have come to Earth for study before: moon rocks and dust from American, Soviet and Chinese missions; samples from two asteroids collected by Japanese probes; and particles from solar wind and a comet gathered by spacecraft. But Mars presents what NASA deems “significant” backward contamination risk, so samples from the red planet fall under a legal category called “Restricted Earth-Return.”

“We have to treat those samples as if they contain hazardous biological materials,” said Nick Benardini, the planetary protection officer at NASA. Dr. Benardini oversees policies and programs that try to prevent Earth’s microbes from contaminating planets or moons in our solar system and extraterrestrial material from hurting Earth.

John Rummel, who served two stints in the office between 1987 and 2008, thinks it is right for the space agency to take the risks seriously, even if they are slim and seem like science fiction. “There are significant unknowns with respect to the biological potential,” he said. “A place like Mars is a planet. We don’t know how it works.”

Part of the point of Mars Sample Return is, of course, to figure out how the planet works — something that cannot be properly done on site because scientists and their myriad instruments cannot travel there yet. The mission has already begun. NASA’s Perseverance spacecraft, which arrived on Mars in 2021, is gathering and caching samples for future pickup. The samples will then be shuttled by the same rover or a robotic helicopter to a lander with a rocket. The rocket will then shoot them to Mars orbit, where a European-built spacecraft will catch the material and fly it back toward Earth.

Once the spacecraft approaches this pale blue dot, optimistically in 2033, the samples will fall to the desert of the expansive Utah Test and Training Range, Earth’s own Martian landscape. Then, scientists can study the samples with the heavy instrumentation that Earth labs allow.

Tiger Team RAMA’s job was to figure out how to make the risk of contamination more of an opportunity than a problem. Their goal was to research what existing contained and clean facilities offered and what the space agency might have to invent.

“We wanted to understand what the state of the state was,” Dr. Harrington said.

To find out, the team visited seven high-containment labs in the United States, one in Britain and one in Singapore as well as super-clean space labs in Japan and Europe. They also visited manufacturers of equipment in these facilities, and those of modular labs.

The biggest technological challenge is that the Sample Receiving Facility must meet two crossed purposes. “Earth doesn’t touch the sample,” Dr. Meyer said. That is the goal of a pristine, clean facility: Keeping substances on Earth from contaminating Martian materials and from giving false signals to scientific studies.

“And the samples don’t touch Earth,” he continued — the backward contamination. The function of a high-containment lab: keeping what is inside, inside.

Cleanrooms require positive air pressure, which means the pressure inside is higher than that outside. Air always flows, then, from the inside to the outside — from higher pressure to lower pressure. It’s just what air does, because physics. Particles are forced out, but do not force their way in.

High-containment labs, though, work the opposite way. They maintain negative air pressure, with lower pressure inside their walls than outside. Particles can waft in, but they cannot sneak out.

NASA needs both positive-pressure space to keep the samples clean and negative-pressure space to keep the samples contained. It is hard to integrate those conditions into the same physical space. It may require creative, concentric structures and sophisticated ventilation systems. No lab on Earth has done it at the scale Mars Sample Return requires because no lab has ever needed to. “We’re not surprised that this doesn’t exist,” Dr. Harrington said.

The best Tiger Team RAMA could do was to see how clean and contained facilities had kept themselves that way and to hope to determine how to best combine them.

Inside the BSL-4 labs the team visited, high efficiency particulate air, or HEPA, filters were ubiquitous. The team learned about sterilization practices, like bathing instruments in gaseous hydrogen peroxide vapors, which killed contaminants on a surface. Work still must be done to find the right way to sterilize the alien material. “Research to understand decontamination, in the context of these samples, is currently underway,” Dr. Harrington said.

In terms of structure, the Sample Receiving Facility could have floors, ceilings and walls coated with epoxy, like BSL-4 labs and cleanrooms sometimes do. The pristine room where scientists constructed a European Mars rover, by contrast, had walls made of welded stainless steel, a material also approved for BSL-4 facility infrastructure. Both materials could work for NASA’s dual purposes.

Tiger Team RAMA also investigated the instruments in Earth-centric cleanrooms that scientists could use to manipulate Martian samples: Microscopes, gloveboxes and robotics like “micromanipulators” let researchers handle materials with precision and without hand-to-sample contact. Scientists remotely studied substances in pure-nitrogen environments, to avoid degrading them, which NASA will need to do as well.

But problems popped up in the details, showing where the state of the state would not work well for NASA. Many of the existing labs were less than 1,000 square feet — way too small for the scale the mission requires. Elevated thresholds or narrow doorways made it hard to get equipment in and out. And existing BSL-4 labs are the Hotels California of bio-facilities: What checks in does not typically leave, at least not without extensive — and sometimes destructive — decontamination. As such, they usually have less instrumentation than a normal lab would. And part of the point of Mars Sample Return is to be able to take advantage of sophisticated scientific devices.

In the end, the team presented a few possibilities to NASA of what shape a Mars sample facility could take: The agency could alter an existing BSL-4 lab to be more pristine. Or, likely requiring more money and time, the agency could build a new brick-and-mortar facility from the Earth-ground up, uniquely designed for its purposes. NASA is also considering middle-ground options, like building a cheaper, modular high-containment facility and plunking it within a harder-shell building.

“There’s a lot that is still on the table that we’re looking at,” Dr. Harrington said.

Whatever NASA decides, the team’s investigation suggested that the process of designing and building a sample study site could take 8 to 12 years — pushing up against the timeline for the actual sample return. Given that, team members recommended that NASA spool up certain plans approximately now.

🪂🌎🔬

Part of the reason to avoid delay is that there will almost certainly be setbacks. The labs that Tiger Team RAMA visited faced bureaucratic hangups, spawning from new regulatory requirements, the vagaries of government money, construction difficulties and imperfect public engagement.

The potential for tardiness presented “significant programmatic risk” to the Mars Sample Return, the team determined. After all, the return is likely to be more complicated, in regards to paperwork, than that of purely terrestrial projects.

NASA wants its project to comply with international planetary-protection policies as well as its own complementary ones. The Sample Receiving Facility would also have to be approved through the National Environmental Policy Act process, which would require producing an environmental-impact statement. The spacecraft and its at-home facility may, additionally, have to deal with National Security Presidential Directive 25, which rules over scientific and technological experiments that could have big environmental effects. This is not to neglect official interest from the Department of Agriculture, the Department of Health and Human Services with the National Institutes of Health and the Centers for Disease Control and Prevention, the Department of Homeland Security and the Occupational Safety and Health Administration, and potentially other state and local governments.

But engaging with the public, not just government agencies, was also key to a project’s success, the team found. Being transparent with the public, Dr. Rummel said, is key not just to gaining public support but to keeping the effort accountable and safe. “Total openness is the only thing that’s going to make this work, which means that you have to do the right thing,” he said.

“If you thought you had any of this that you had to keep secret, then you shouldn’t be doing it,” he added.

The facility’s builders will have to consider public interest, not just research, when they communicate. When Scott Hanton, editorial director of the publication Lab Manager, thinks about the perception and communication challenges NASA will face with the Sample Receiving Facility, two more acronyms come to mind: NIMBY and WIIFM. Not In My Backyard and What’s in It For Me, which have to be balanced.

The answer to the latter, Dr. Hanton thinks, has to come from a resident’s personal viewpoint. “Not just from the scientist’s perspective of learning something new,” he said. “But why should the neighborhood, the region, the state, the country, embark on this investment and this risk?”

Having community advisory groups that purposefully include vocal critics — which he calls putting “a bandit on the train” — could create good faith.

Dr. Hanton nevertheless sees, in this extraterrestrial risk, a terrestrial boon. “It feels to me like it’s a new problem,” he said. “It’s going to need a new answer.” NASA’s investment in building a secure facility could result in better biolabs in general.

“There’s going to be very interesting technical challenges,” he said, “that could provide, frankly, more benefit to humankind than whatever they learn from the sample.”

Dr. Harrington is, of course, excited about the samples. Mars is a geological and environmental time capsule, revealing what Earth may have been like eons ago. “We’ll really be able to tell a lot about the Earth’s evolution,” Dr. Harrington said.

It could bring us a small step closer to understanding how, say, a planet produces beings that produce a spacecraft that goes to another world and then brings that world back to this one.

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Arctic lakes are vanishing in surprise climate finding - Phys.org

An aerial view of a large Arctic lake, nearly completely dry. Credit: David Swanson/National Park Service

The Arctic is no stranger to loss. As the region warms nearly four times faster than the rest of the world, glaciers collapse, wildlife suffers and habitats continue to disappear at a record pace.

Now, a new threat has become apparent: Arctic lakes are drying up, according to research published in the journal Nature Climate Change. The study, led by University of Florida Department of Biology postdoctoral researcher Elizabeth Webb, flashes a new warning light on the global climate dashboard.

Webb's research reveals that over the past 20 years, Arctic lakes have shrunk or dried completely across the pan-Arctic, a region spanning the northern parts of Canada, Russia, Greenland, Scandinavia and Alaska. The findings offer clues about why the mass drying is happening and how the loss can be slowed.

The vanishing lakes act as cornerstones of the Arctic ecosystem. They provide a critical source of fresh water for local Indigenous communities and industries. Threatened and endangered species, including migratory birds and aquatic creatures, also rely on the lake habitats for survival.

The lake decline comes as a surprise. Scientists had predicted that climate change would initially expand lakes across the tundra, due to land surface changes resulting from melting ground ice, with eventual drying in the mid-21st or 22nd century. Instead, it appears that thawing permafrost, the frozen soil that blankets the Arctic, may drain lakes and outweigh this expansion effect, says Webb. The team theorized that thawing permafrost may decrease lake area by creating drainage channels and increasing soil erosion into the lakes.

"Our findings suggest that permafrost thaw is occurring even faster than we as a community had anticipated," Webb said. "It also indicates that the region is likely on a trajectory toward more landscape-scale drainage in the future."

An aerial view of a large Arctic lake, nearly completely dry. Credit: David Swanson/National Park Service

In addition to rising temperatures, the study also revealed that increases in autumn rainfall cause permafrost degradation and lake drainage. "It might seem counterintuitive that increasing rainfall reduces surface water," said Jeremy Lichstein, Webb's advisor and a co-author of the study. "But it turns out the physical explanation was already in the scientific literature: rainwater carries heat into the soil and accelerates permafrost thaw, which can open up underground channels that drain the surface."

If accelerated permafrost thaw is to blame, that's unwelcome news. The Arctic permafrost is a natural warehouse of preserved organic matter and planet-warming gases.

"Permafrost soils store nearly two times as much carbon as the atmosphere," Webb said. "There's a lot of ongoing research suggesting that as permafrost thaws, this carbon is vulnerable to being released to the atmosphere in the form of methane and carbon dioxide."

There is a silver lining in the researcher's findings. Previous models of lake dynamics predicted lake expansion, which thaws the surrounding permafrost. But because lakes are drying, permafrost near the lakes is likely not thawing as fast.

"It's not immediately clear exactly what the trade-offs are, but we do know that lake expansion causes carbon losses orders of magnitude higher than occurs in surrounding regions," Webb said.

To achieve their results, Webb's team used satellite data to identify broad trends in surface water change across the Arctic. Known as remote sensing, satellite imagery helps answer broad-scale questions, says Webb.

An aerial view of Arctic lakes showing one significantly drained. Credit: David Swanson/National Park Service

"One of the things that I really like about using remote sensing is that you can answer what seemed like impossibly big questions—we have the ability to answer them now," Webb said. "It's only in the past five, 10 years that we've had the computing power and resources to pull this off."

The research team used a machine-learning approach to examine the climate change mechanisms responsible for lake area change. By harnessing large ensembles of satellite images to assess patterns of surface water loss, they were able to analyze decades of data across the Arctic. Their work relied on robust programs, including Google Earth Engine and the Python platform on UF's HiPerGator supercomputer, to query large data sets and run models.

Webb initially set out to explore a different topic altogether: Arctic albedo, or surface reflectivity. Webb's earlier work in Environmental Research Letters showed that surface water is an important driver of albedo change, but she struggled to locate studies that detailed why the surface waters were changing in the first place. "I wrote the paper I wanted to cite for my albedo work," she said.

To curtail the lakes' demise, recent research in Frontiers in Environmental Science shows that perhaps the best way to save permafrost is by cutting fossil fuel emissions. Reducing carbon emissions could put the planet back on track by limiting global temperature rise.

"The snowball is already rolling," Webb said, stating that we need to act now to slow these changes. "It's not going to work to keep on doing what we're doing."

---

Explore further

Western Siberian rivers and lakes emit greenhouse gases into the atmosphere

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More information: Elizabeth E. Webb et al, Permafrost thaw drives surface water decline across lake-rich regions of the Arctic, Nature Climate Change (2022). DOI: 10.1038/s41558-022-01455-w

E E Webb et al, Surface water, vegetation, and fire as drivers of the terrestrial Arctic-boreal albedo feedback, Environmental Research Letters (2021). DOI: 10.1088/1748-9326/ac14ea

Benjamin W. Abbott et al, We Must Stop Fossil Fuel Emissions to Protect Permafrost Ecosystems, Frontiers in Environmental Science (2022). DOI: 10.3389/fenvs.2022.889428

Permafrost Discovery Gateway: arcticdata.io/catalog/portals/ … frost/Imagery-Viewer

Provided by University of Florida

Citation: Arctic lakes are vanishing in surprise climate finding (2022, August 30) retrieved 31 August 2022 from https://ift.tt/wJaTs0q

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Guy Stumbles Upon Remains of Massive Dinosaur in His Backyard - CNET

An unassuming backyard in central Portugal has turned into an excavation site for the remains of what could be a record-setting dinosaur.  

The excitement started in 2017, when a man in the city of Pombal spotted fragments of fossilized bones while digging up his garden to build an extension. He contacted researchers with the stunning find, and since then, paleontologists have been busy at the site unearthing fossilized fragments of what they believe could be the largest sauropod found in Europe yet.

Sauropods, which count among the biggest animals to have lived on land, had small heads atop long necks, long tails and four thick legs. They roved Earth 150 million years ago, reaching staggering heights of 39 feet (12 meters) and lengths of 82 feet (25 meters).   

Earlier this month, the research team from Portugal and Spain collected vertebrae of the possible brachiosaurid sauropod from the garden, as well as ribs that include a whopper around 10 feet (3 meters) long. The way the fragments are situated leaves the researchers hopeful more reptilian treasures await at the Pombal site.  

"It is not usual to find all the ribs of an animal like this, let alone in this position, maintaining their original anatomical position," Elisabete Malafaia, a postdoctoral researcher at the Faculty of Sciences of the University of Lisbon, said in a statement. "This mode of preservation is relatively uncommon in the fossil record of dinosaurs, in particular sauropods, from the Portuguese Upper Jurassic." 

The researchers will continue to excavate in the Pombal garden, and possibly beyond, to better understand the region's fossil record of Late Jurassic vertebrates. And the owner of the house will no doubt be on high alert next time he goes outside to plant a few perennials.  

Not the typical garden find. 

Faculty of Sciences of the University of Lisbon

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SpaceX Falcon 9 Starlink launch from Space Force Station - Florida Today

Hubble still delivering as James Webb telescope snaps early universe images - Business Insider

The Hubble Space Telescope launched in 1990 and has provided humanity a front-row seat to the cosmos for more than three decades.

NASA

• Since its launch in 1990, the Hubble Space Telescope has made revolutionary achievements in astronomy.
• The new James Webb Space Telescope is popular, but Hubble has skills, like capturing visible and ultraviolet light, that Webb doesn't.
• The two telescopes will team up to study the cosmos in even greater detail. 

For three decades, the Hubble Space Telescope has delivered breathtaking cosmic views.

As the world raves about NASA's new James Webb Space Telescope, aging Hubble continues to be an astronomical workhorse, providing important observations of the universe, while Webb soaks up the spotlight.

But as a pair, the telescopes are even more powerful than they are alone. Together, the space-based telescopes will give astronomers a more complete view and understanding of galaxies, stars, and planets than ever before.

"The Webb Space Telescope is good news for astronomy, and good news for the Hubble Space Telescope as well, since Webb and Hubble enhance and complement each other's unique capabilities," Jennifer Wiseman, senior project scientist for the Hubble Space Telescope at NASA's Goddard Space Flight Center, told Insider.

"Hubble's science return is expected to be strong, and even enhanced throughout this decade as Webb and Hubble unveil the universe together."

Through Hubble's looking glass

Hubble being deployed from Discovery in 1990.

NASA/IMAX

Since Galileo Galilei constructed his telescope in 1609, astronomers have turned these tools to the sky. Astronomers developed these instruments significantly over time, allowing them to peer even deeper into the universe.

But their observations were constrained by Earth's atmosphere, which absorbs light before it reaches ground-based telescopes. Enter space-based telescopes. By sitting high above the distortion of Earth's atmosphere and away from light-polluted cities, observatories like Hubble provide, as NASA puts it, "an unobstructed view of the universe." 

Hubble launched on the space shuttle Discovery on April 24, 1990. Though it was originally scheduled for only 15 years of service, it still zips through space about 340 miles above Earth's surface, circling the planet every 97 minutes.

"Hubble is in good technical condition, even 32 years after its launch, with a strong suite of science instruments on board," Wiseman said.

The Pillars of Creation in the Eagle Nebula, taken by the Hubble Space Telescope in 1995.

NASA, Jeff Hester, and Paul Scowen (Arizona State University)

Over the years, Hubble's images have played a significant part in our understanding of the universe. It provided evidence of supermassive black holes at the centers of galaxies and measurement of the expansion rate of the universe. Hubble also helped discover and characterize the mysterious dark energy causing that expansion by pulling galaxies apart. Among its most iconic achievements is its Pillars of Creation image, taken in 1995, which shows newly formed stars glowing in the Eagle Nebula.

And Hubble's still taking stunning pictures, even after Webb began delivering images from its scientific observations in July. Recently, Hubble snapped an image of star-studded NGC 6540, a globular cluster in the constellation Sagittarius. 

A globular cluster NGC 6540 in the constellation Sagittarius, which was captured by the Hubble Space Telescope.

ESA/Hubble & NASA, R. Cohen

Webb's infrared gaze

Both Webb and Hubble are space-based telescopes, but they differ in many ways. Hubble sees ultraviolet light, visible light, and a small slice of infrared, while Webb will primarily look at the universe in infrared.

Webb — which is 100 times more powerful than Hubble — will be able to peer at objects whose light was emitted more than 13.5 billion years ago, which Hubble can't see. This is because this light has been shifted into the infrared wavelengths that Webb is specifically designed to detect. 

But because Webb has been designed this way, it will also miss celestial objects in the visible and ultraviolet light that Hubble can see.

"In fact, Hubble is the only major class observatory that can access UV wavelengths," Wiseman said.

A deep field image from the Hubble space telescope, left, and a deep field image from the James Webb Space Telescope, right.

NASA/STScI; NASA/ESA/CSA/STScI

A telescopic twosome

While Webb has been referred to as Hubble's successor, the two space-based observatories will be teaming up to unveil the universe together.

Wiseman points to how they'll provide insights into how stars are born within the clouds of cosmic dust and scattered throughout most galaxies. "Hubble, for example, can detect and analyze in detail the hot blue and UV light blazing from star-forming nebulae in nearby galaxies," Wiseman said, adding, "That can be compared to the vigor of star formation in the early universe as detected with Webb."

The two space-based telescopes will also combine their gazes to peer at the atmospheres of other worlds, looking for signs they might harbor life. 

Astronomers typically look for the ingredients that sustain earthly life — liquid water, a continuous source of energy, carbon, and other elements — when hunting for life-supporting planets. In 2001, Hubble made the first direct measurement of an exoplanet's atmosphere. 

"In our own galaxy, the understanding of planets within and beyond our own solar system will be greatly enhanced with the Webb and Hubble combo," Wiseman said, adding, "Signatures of water, methane, and other atmospheric constituents will be identified using the combined spectroscopic capabilities of Webb and Hubble."

In 2001, Hubble made the first direct detection of an atmosphere of world orbiting a star beyond our solar system. Artist's impression of the planet, which orbits a star called HD 209458.

G. Bacon (STScI/AVL)

And though Webb may be seen as the shiny new toy in astronomy, Hubble's unique capabilities in capturing visible and ultraviolet light still make it a sought-after tool for understanding the cosmos. "Hubble is actually at its peak scientific performance now," Wiseman said. That's thanks to a team of NASA technical experts on the ground who monitor and quickly address any technical challenges that arise, she added.

"The number of proposals from scientists around the world who want to use Hubble has risen to over 1,000 per year, with only the top fraction of these selected for actual observations," Wiseman said, adding, "Many of these complement proposed Webb observations."

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Lightning strikes Artemis 1 launch pad 2 days before liftoff (video) - Space.com

This is why launch pads have lightning towers.

Lightning crackled today (Aug. 27) over Launch Pad 39B at NASA's Kennedy Space Center in Florida, which will host the highly anticipated liftoff of the agency's Artemis 1 moon mission on Monday morning (Aug. 29). 

The bolts came close to the Artemis 1 stack — a Space Launch System (SLS) megarocket topped by an Orion crew capsule — with three even hitting Pad 39B's lightning towers.

Related: NASA's Artemis 1 moon mission: Live updates
More: NASA's Artemis 1 moon mission explained in photos

Lightning strikes next to Launch Complex 39B at Kennedy Space Center a few moments ago as NASA’s Space Launch System rocket and Artemis I await their Monday launch during a two-hour window opening at 8:33 a.m. EDT. pic.twitter.com/UsfBX1Q2u8August 27, 2022

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There's no cause for alarm; the towers were doing their job, shunting dangerous strikes away from valuable spaceflight hardware. One of 39B's three towers was similarly struck in early April during an Artemis 1 fueling test, for example, and the SLS and Orion emerged unscathed.

In a blog post update (opens in new tab) this evening, NASA officials said the three strikes today were likely "of low magnitude." Still, the agency is investigating whether they may have affected the Artemis 1 stack or Pad 39B.

"A weather team has begun an assessment that includes collecting voltage and current data, as well as imagery," NASA officials wrote in the update. "The data will be shared with a team of experts on electromagnetic environment efforts who will determine if any constraints on vehicle or ground systems were violated. Engineers will conduct a walkdown at the pad tonight, and if needed, conduct additional assessments with subsystems experts."

Artemis 1 is the first mission of NASA's Artemis program of lunar exploration, as well as the debut flight of the SLS. The powerful rocket will launch Orion on an uncrewed mission to lunar orbit that will last six weeks from liftoff to splashdown. The main goal is to demonstrate that both vehicles are ready to start launching astronauts to the moon and other deep-space destinations.

Related stories:

The weather isn't great on the Space Coast today, as the lightning strikes show. But it's expected to clear up considerably by launch day; weather forecasters with the U.S. Space Force say there's a 70% chance that Mother Nature will cooperate on Monday morning.

If the weather or technical issues nix that liftoff attempt, however, NASA has two backup opportunities in the current launch window to shoot for — Sept. 2 and Sept. 5.

Editor's note: This story was updated at 6:45 p.m. EDT on Aug. 27 to include information from the NASA blog post update.

Mike Wall is the author of "Out There (opens in new tab)" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall (opens in new tab). Follow us on Twitter @Spacedotcom (opens in new tab) or on Facebook (opens in new tab).  

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Mucus Is So Handy That We Evolve It Over And Over Again, Finds Study - ScienceAlert

The animal kingdom is practically dripping in mucus.

Amphibians, snails, and slugs are among the more famous masters of mucus, but even the loneliest microorganism can ooze a viscous slime from time to time.

In our own species, mucus is produced in the mouth, the nose, the throat, the lungs, the gut, the cervix, and the urinary tract, all for a variety of purposes.

Yet the origin of the world's slime is a mystery.

Despite the many similarities between mucuses, many forms have evolved in parallel and not in a branching, tree-like way.

Across glands and between mammals, a small study has found many mucus genes do not in fact share a common ancestor.

This is unusual because most genes with similar functions originate from a shared ancestral gene that is passed down through the generations because it bestows benefits to survival.

Even in our own species, the genes that encode for mucus proteins belong to several families. One secretes gel-forming mucus proteins, while another produces mucus proteins bound to a cell's membrane. There are also 'orphan' genes that encode for mucus production that don't quite fit anywhere else.

Each of these separate lineages probably evolved independently, and researchers now think they've figured out where they came from.

When comparing mucus-encoding genes, known as mucin genes, across 49 mammal species, the team found non-mucin proteins can evolve into slimy, mucin proteins when short repeated chains of amino acids (protein building blocks) are added again.

Among all the mucin genes studied, such random repeats were counted 15 different times.

In other words, some genes in mammals that encode for non-mucin proteins lean towards sliminess over time. Those proteins that are rich in the organic acid proline are most likely to go gooey with the generations, according to the authors of the current study.

"I don't think it was previously known that protein function can evolve this way, from a protein gaining repeated sequences," says evolutionary biologist Omer Gokcumen from the University at Buffalo.

"A protein that isn't a mucin becomes a mucin just by gaining repeats. This is an important way that evolution makes slime. It's an evolutionary trick, and we now document this happening over and over again."

The authors chanced upon their discovery when studying human saliva. During experiments, they noticed one particular mucin gene in humans had similarities to another seen in mice.

When they tried to find a common ancestry, however, they failed.

The mucin gene in mice appeared to have evolved independently, although a portion of the gene shared a structure seen in the genes responsible for human tears, which aren't considered mucus.

"We think that somehow that tear gene ends up repurposed," explains Gokcumen.

"It gains the repeats that give it the mucin function, and it's now abundantly expressed in mouse and rat saliva."

If Gokcumen and his colleagues are right, their results offer scientists a new genetic evolutionary mechanism – the formation of a new gene function without the usual process of a gene duplication event.

This parallel series of mutations in unrelated genes resulting in the same function is an example of convergent evolution (where selective pressure molds the same function from unrelated biological origins, like bat and bird wings) happening on the genetic level.

"If these mucins keep evolving from non-mucins over and over again in different species at different times, it suggests that there is some sort of adaptive pressure that makes it beneficial," explains evolutionary geneticist Petar Pajic from the University at Buffalo.

"And then, at the other end of the spectrum, maybe if this mechanism goes 'off the rails' – happening too much, or in the wrong tissue – then maybe it can lead to disease like certain cancers or mucosal illnesses."

While studying mucus might not sound like the most magical of scientific endeavors, it's hardly a pursuit to sniff at.

The study was published in Science Advances.

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Artemis I Path to the Pad: Roll to the Pad - NASA

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NASA's Webb telescope captures first evidence of carbon dioxide on an exoplanet - CNN

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(CNN)NASA's James Webb Space Telescope has captured the first clear evidence of carbon dioxide in the atmosphere of an exoplanet, a planet outside our solar system.

The exoplanet, WASP-39b, is a hot gas giant orbiting a sunlike star that is 700 light-years from Earth and part of a larger Webb investigation that includes two other transiting planets, according to NASA. Understanding the atmospheric makeup of planets like WASP-39b is critical for knowing their origins and how they evolved, the agency noted in a news release.

This illustration shows what exoplanet WASP-39 b could look like, based on current understanding of the planet.

"Carbon dioxide molecules are sensitive tracers of the story of planet formation," said Mike Line, an associate professor in Arizona State University's School of Earth and Space Exploration, in the news release. Line is a member of the JWST Transiting Exoplanet Community Early Release Science team, which conducted the investigation.

The team made the carbon dioxide observation using the telescope's Near-Infrared Spectrograph -- one of Webb's four scientific instruments -- to observe WASP-39b's atmosphere. Their research is part of the Early Release Science Program, an initiative designed to provide data from the telescope to the exoplanet research community as soon as possible, guiding further scientific study and discovery.

This latest finding has been accepted for publication in the journal Nature.

"By measuring this carbon dioxide feature, we can determine how much solid versus how much gaseous material was used to form this gas giant planet," Line added. "In the coming decade, JWST will make this measurement for a variety of planets, providing insight into the details of how planets form and the uniqueness of our own solar system."

A new era in exoplanet research

The highly sensitive Webb telescope launched on Christmas Day 2021 toward its current orbit 1.5 million kilometers (nearly 932,000 miles) from Earth. By observing the universe with longer wavelengths of light than other space telescopes use, Webb can study the beginning of time more closely, hunt for unobserved formations among the first galaxies, and peer inside dust clouds where stars and planetary systems are currently forming.

In the captured spectrum of the planet's atmosphere, the researchers saw a small hill between 4.1 and 4.6 microns -- a "clear signal of carbon dioxide," said team leader Natalie Batalha, a professor of astronomy and astrophysics at the University of California at Santa Cruz, in the release. (A micron is a unit of length equal to one millionth of a meter.)

"Depending on the atmosphere's composition, thickness, and cloudiness, it absorbs some colors of light more than others -- making the planet appear larger," said team member Munazza Alam, a postdoctoral fellow in the Earth & Planets Laboratory at the Carnegie Institution for Science. "We can analyze these miniscule differences in the size of the planet to reveal the atmosphere's chemical makeup."

Access to this part of the light spectrum -- which the Webb telescope makes possible -- is crucial for measuring abundances of gases such as methane and water, as well as carbon dioxide, which are thought to exist in many exoplanets, according to NASA. Because individual gases absorb different combinations of colors, researchers can examine "small differences in brightness of the transmitted light across a spectrum of wavelengths to determine exactly what an atmosphere is made of," according to NASA.

Previously, NASA's Hubble and Spitzer telescopes discovered water vapor, sodium and potassium in the planet's atmosphere. "Previous observations of this planet with Hubble and Spitzer had given us tantalizing hints that carbon dioxide could be present," Batalha said. "The data from JWST showed an unequivocal carbon dioxide feature that was so prominent it was practically shouting at us."

"As soon as the data appeared on my screen, the whopping carbon dioxide feature grabbed me," said team member Zafar Rustamkulov, a graduate student of in the Morton K. Blaustein Department of Earth & Planetary Sciences at Johns Hopkins University, in a news release. "It was a special moment, crossing an important threshold in exoplanet sciences," he added.

Discovered in 2011, WASP-39b's mass is about the same as Saturn's and roughly a fourth of Jupiter's, while its diameter is 1.3 times greater than Jupiter's. Since the exoplanet orbits very close to its star, it completes one circuit in slightly over four Earth days.

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Scientists discover fossils of giant sea lizard that ruled the oceans 66 million years ago - Phys.org

Artist's representation of Thalassotitan atrox. Credit: Andrey Atuchin

Researchers have discovered a huge new mosasaur from Morocco, named Thalassotitan atrox, which filled the apex predator niche. With massive jaws and teeth like those of killer whales, Thalassotitan hunted other marine reptiles—plesiosaurs, sea turtles, and other mosasaurs.

At the end of the Cretaceous period, 66 million years ago, sea monsters really existed. While dinosaurs flourished on land, the seas were ruled by the mosasaurs, giant marine reptiles.

Mosasaurs weren't dinosaurs, but enormous marine lizards growing up to 12 meters (40 feet) in length. They were distant relatives of modern iguanas and monitor lizards.

Mosasaurs looked like a Komodo dragon with flippers instead of legs, and a shark-like tail fin. Mosasaurs became larger and more specialized in the last 25 million years of the Cretaceous, taking niches once filled by marine reptiles like plesiosaurs and ichthyosaurs. Some evolved to eat small prey like fish and squid. Others crushed ammonites and clams. The new mosasaur, named Thalassotitan atrox, evolved to prey on all the other marine reptiles.

The remains of the new species were dug up in Morocco, about an hour outside Casablanca. Here, near the end of the Cretaceous, the Atlantic flooded northern Africa. Nutrient rich waters upwelling from the depths fed blooms of plankton. Those fed small fish, feeding larger fish, which fed mosasaurs and plesiosaurs—and so on, with these marine reptiles becoming food for the giant, carnivorous Thalassotitan.

Nick Longrich with the mosasaur fossil. Credit: Nick Longrich

Thalassotitan, had an enormous skull measuring 1.4 meters (5 feet long), and grew to nearly 30 feet (9 meters) long, the size of a killer whale. While most mosasaurs had long jaws and slender teeth for catching fish, Thalassotitan had a short, wide muzzle and massive, conical teeth like those of an orca. These let it seize and rip apart huge prey. These adaptations suggest Thalassotitan was an apex predator, sitting at the top of the food chain. The giant mosasaur occupied the same ecological niche as today's killer whales and great white sharks.

Thalassotitan's teeth are often broken and worn, however eating fish wouldn't have produced this sort of tooth wear. Instead, this suggests that the giant mosasaur attacked other marine reptiles, chipping, breaking, and grinding its teeth as it bit into their bones and tore them apart. Some teeth are so heavily damaged they have been almost ground down to the root.

Fossilized remains of prey

Remarkably, possible remains of Thalassotitan's victims have been discovered. Fossils from the same beds show damage from acids, with teeth and bone eaten away. Fossils with this peculiar damage include large predatory fish, a sea turtle, a half-meter long plesiosaur head, and jaws and skulls of at least three different mosasaur species. They would have been digested in Thalassotitan's stomach before it spat out their bones.

Size comparison of Thalassotitan atrox. Credit: Nick Longrich

"It's circumstantial evidence," said Dr. Nick Longrich, Senior Lecturer from the Milner Center for Evolution at the University of Bath and lead author on the study, published in Cretaceous Research.

"We can't say for certain which species of animal ate all these other mosasaurs. But we have the bones of marine reptiles killed and eaten by a large predator.

"And in the same location, we find Thalassotitan, a species that fits the profile of the killer—it's a mosasaur specialized to prey on other marine reptiles. That's probably not a coincidence."

Thalassotitan was a threat to everything in the oceans—including other Thalassotitan. The huge mosasaurs bear injuries sustained in violent combat with other mosasaurs, with injuries to their face and jaws sustained in fights. Other mosasaurs show similar injuries, but in Thalassotitan these wounds were exceptionally common, suggesting frequent, intense fights over feeding grounds or mates.

"Thalassotitan was an amazing, terrifying animal," said Dr. Nick Longrich, who led the study. "Imagine a Komodo Dragon crossed with a great white shark crossed with a T. rex crossed with a killer whale."

The new mosasaur lived in the final million years of the Age of Dinosaurs, a contemporary of animals like T. rex and Triceratops. Along with recent discoveries of mosasaurs from Morocco, it suggests that mosasaurs weren't in decline before the asteroid impact that drove the Cretaceous mass extinction. Instead, they flourished.

Map of distribution of Thalassotitan. Credit: Nick Longrich

Professor Nour-Eddine Jalil, a co-author on the paper from the Museum of Natural History in Paris, said: "The phosphate fossils of Morocco offer an unparalleled window on the paleobiodiversity at the end of Cretaceous.

"They tell us how life was rich and diversified just before the end of the 'dinosaur era," where animals had to specialize to have a place in their ecosystems. Thalassotitan completes the picture by taking on the role of the megapredator at the top of the food chain."

"There's so much more to be done," said Longrich. "Morocco has one of the richest and most diverse marine faunas known from the Cretaceous. We're just getting started understanding the diversity and the biology of the mosasaurs."

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Giant sea lizard fossil shows diversity of life before asteroid hit

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More information: Nicholas R. Longrich et al, Thalassotitan atrox, a giant predatory mosasaurid (Squamata) from the Upper Maastrichtian Phosphates of Morocco, Cretaceous Research (2022). DOI: 10.1016/j.cretres.2022.105315

Dr. Longrich has written a blog about the research here: https://www.nicklongrich.com/blog/thalassotitan-the-killer-mosasaur

Provided by University of Bath

Citation: Scientists discover fossils of giant sea lizard that ruled the oceans 66 million years ago (2022, August 24) retrieved 24 August 2022 from https://ift.tt/9acyo7L

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