17th century scientist Christiaan Huygens set his sights on faraway Saturn, but he may have been nearsighted.
Huygens is known, in part, for discovering Saturn’s largest moon, Titan, and deducing the shape of the planet’s rings. But by some accounts, the Dutch scientist’s telescopes produced fuzzier views than others of the time despite having well-crafted lenses.
That may be because Huygens needed glasses, astronomer Alexander Pietrow proposes March 1 in Notes and Records: the Royal Society Journal of the History of Science. To make his telescopes, Huygens combined two lenses, an objective and an eyepiece, positioned at either end of the telescope. Huygens experimented with different lenses to find combinations that, to his eye, created a sharp image, eventually creating a table to keep track of which combinations to use to obtain a given magnification. But when compared with modern-day knowledge of optics, Huygens’ calculations were a bit off, says Pietrow, of the Leibniz Institute for Astrophysics Potsdam in Germany.
One possible explanation: Huygens selected lenses based on his flawed vision. Historical records indicate that Huygens’ father was nearsighted, so it wouldn’t be surprising if Christiaan Huygens also suffered from the often-hereditary affliction.
Assuming that’s the reason for the mismatch, Pietrow calculates that Huygens had 20/70 vision: What someone with normal vision could read from 70 feet away, Huygens could read only from 20 feet. If so, that could be why Huygens’ telescopes never quite reached their potential.
Weird materials called Weyl metals might reveal the secrets of how Earth gets its magnetic field.
The substances could generate a dynamo effect, the process by which a swirling, electrically conductive material creates a magnetic field, a team of scientists reports in the Oct. 26 Physical Review Letters.
Dynamos are common in the universe, producing the magnetic fields of the Earth, the sun and other stars and galaxies. But scientists still don’t fully understand the details of how dynamos create magnetic fields. And, unfortunately, making a dynamo in the lab is no easy task, requiring researchers to rapidly spin giant tanks of a liquefied metal, such as sodium (SN: 5/18/13, p. 26). First discovered in 2015, Weyl metals are topological materials, meaning that their behavior is governed by a branch of mathematics called topology, the study of shapes like doughnuts and knots (SN: 8/22/15, p. 11). Electrons in Weyl metals move around in bizarre ways, behaving as if they are massless.
Within these materials, the researchers discovered, electrons are subject to the same set of equations that describes the behavior of liquids known to form dynamos, such as molten iron in the Earth’s outer core. The team’s calculations suggest that, under the right conditions, it should be possible to make a dynamo from solid Weyl metals.
It might be easier to create such dynamos in the lab, as they don’t require large quantities of swirling liquid metals. Instead, the electrons in a small chunk of Weyl metal could flow like a fluid, taking the place of the liquid metal. The result is still theoretical. But if the idea works, scientists may be able to use Weyl metals to reproduce the conditions that exist within the Earth, and better understand how its magnetic field forms.
When the [Atomic Energy Commission] first cast its eye on the island of Amchitka as a possible site for the testing of underground nuclear explosions, howls of anguish went up; the island is part of the Aleutians National Wildlife Refuge, created to preserve the colonies of nesting birds and some 2,500 sea otters that live there…— Science News, November 9, 1968
Update The commission said underground nuclear testing would not harm the otters, but the fears of conservationists were well-founded: A test in 1971 killed more than 900 otters on the Aleutian island. Some otters remained around Amchitka, but 602 otters were relocated in 1965–1972 to Oregon, southeast Alaska, Washington and British Columbia — areas where hunting had wiped them out. All but the Oregon population thrived, and today more than 25,000 otters live near the coastal shores where once they were extinct.
“They were sitting on the precipice,” says James Bodkin, who is a coastal ecologist at the U.S. Geological Survey. “It’s been a great conservation story.”
Neandertals are shaking off their reputation as head bangers.
Our close evolutionary cousins experienced plenty of head injuries, but no more so than late Stone Age humans did, a study suggests. Rates of fractures and other bone damage in a large sample of Neandertal and ancient Homo sapiens skulls roughly match rates previously reported for human foragers and farmers who have lived within the past 10,000 years, concludes a team led by paleoanthropologist Katerina Harvati of the University of Tübingen in Germany. Males suffered the bulk of harmful head knocks, whether they were Neandertals or ancient humans, the scientists report online November 14 in Nature.
“Our results suggest that Neandertal lifestyles were not more dangerous than those of early modern Europeans,” Harvati says.
Until recently, researchers depicted Neandertals, who inhabited Europe and Asia between around 400,000 and 40,000 years ago, as especially prone to head injuries. Serious damage to small numbers of Neandertal skulls fueled a view that these hominids led dangerous lives. Proposed causes of Neandertal noggin wounds have included fighting, attacks by cave bears and other carnivores and close-range hunting of large prey animals.
Paleoanthropologist Erik Trinkaus of Washington University in St. Louis coauthored an influential 1995 paper arguing that Neandertals incurred an unusually large number of head and upper-body injuries. Trinkaus recanted that conclusion in 2012, though. All sorts of causes, including accidents and fossilization, could have resulted in Neandertal skull damage observed in relatively small fossil samples, he contended (SN: 5/27/17, p. 13). Harvati’s study further undercuts the argument that Neandertals engaged in a lot of violent behavior, Trinkaus says.
Still, the idea that Neandertals frequently got their heads bonked during crude, close-up attacks on prey has persisted, says paleoanthropologist David Frayer of the University of Kansas in Lawrence. The new report highlights the harsh reality that, for Neandertals and ancient humans alike, “head trauma, no matter the level of technological or social complexity, or population density, was common.”
Harvati’s group analyzed data for 114 Neandertal skulls and 90 H. sapiens skulls. All of these fossils were found in Eurasia and date to between around 80,000 and 20,000 years ago. One or more head injuries appeared in nine Neandertals and 12 ancient humans. After statistically accounting for individuals’ sex, age at death, geographic locations and state of bone preservation, the investigators estimated comparable levels of skull damage in the two species. Statistical models run by the team indicate that skull injuries affected an average of 4 percent to 33 percent of Neandertals, and 2 percent to 34 percent of ancient humans.
Estimated prevalence ranges that large likely reflect factors that varied from one locality to another, such as resource availability and hunting conditions, the researchers say.
Neandertals with head wounds included more individuals under age 30 than observed among their human counterparts. Neandertals may have suffered more head injuries early in life, the researchers say. It’s also possible that Neandertals died more often from head injuries than Stone Age humans did.
Researchers have yet to establish whether Neandertals experienced especially high levels of damage to body parts other than the head, writes paleoanthropologist Marta Mirazón Lahr of the University of Cambridge in a commentary in Nature accompanying the new study.
Oceans may be shrinking — Science News, March 10, 1973
The oceans of the world may be gradually shrinking, leaking slowly away into the Earth’s mantle…. Although the oceans are constantly being slowly augmented by water carried up from Earth’s interior by volcanic activity … some process such as sea-floor spreading seems to be letting the water seep away more rapidly than it is replaced.
Update Scientists traced the ocean’s leak to subduction zones, areas where tectonic plates collide and the heavier of the two sinks into the mantle. It’s still unclear how much water has cycled between the deep ocean and mantle through the ages. A 2019 analysis suggests that sea levels have dropped by an average of up to 130 meters over the last 230 million years, in part due to Pangea’s breakup creating new subduction zones. Meanwhile, molten rock that bubbles up from the mantle as continents drift apart may “rain” water back into the ocean, scientists reported in 2022. But since Earth’s mantle can hold more water as it cools (SN: 6/13/14), the oceans’ mass might shrink by 20 percent every billion years.
THE WOODLANDS, TEXAS — Martian dirt may have all the necessary nutrients for growing rice, one of humankind’s most important foods, planetary scientist Abhilash Ramachandran reported March 13 at the Lunar and Planetary Science Conference. However, the plant may need a bit of help to survive amid perchlorate, a chemical that can be toxic to plants and has been detected on Mars’ surface (SN: 11/18/20).
“We want to send humans to Mars … but we cannot take everything there. It’s going to be expensive,” says Ramachandran, of the University of Arkansas in Fayetteville. Growing rice there would be ideal, because it’s easy to prepare, he says. “You just peel off the husk and start boiling.” Ramachandran and his colleagues grew rice plants in a Martian soil simulant made of Mojave Desert basalt. They also grew rice in pure potting mix as well as several mixtures of the potting mix and soil simulant. All pots were watered once or twice a day.
Rice plants did grow in the synthetic Mars dirt, the team found. However, the plants developed slighter shoots and wispier roots than the plants that sprouted from the potting mix and hybrid soils. Even replacing just 25 percent of the simulant with potting mix helped heaps, they found.
The researchers also tried growing rice in soil with added perchlorate. They sourced one wild rice variety and two cultivars with a genetic mutation — modified for resilience against environmental stressors like drought — and grew them in Mars-like dirt with and without perchlorate (SN: 9/24/21).
No rice plants grew amid a concentration of 3 grams of perchlorate per kilogram of soil. But when the concentration was just 1 gram per kilogram, one of the mutant lines grew both a shoot and a root, while the wild variety managed to grow a root.
The findings suggest that by tinkering with the successful mutant’s modified gene, SnRK1a, humans might eventually be able to develop a rice cultivar suitable for Mars.
A new species of hulking ancient herbivore would have overshadowed its relatives.
Fossils found in Poland belong to a new species that roamed during the Late Triassic, a period some 237 million to 201 million years ago, researchers report November 22 in Science. But unlike most of the enormous animals who lived during that time period, this new creature isn’t a dinosaur — it’s a dicynodont.
Dicynodonts are a group of ancient four-legged animals that are related to mammals’ ancestors. They’re a diverse group, but the new species is far larger than any other dicynodont found to date. The elephant-sized creature was more than 4.5 meters long and probably weighed about nine tons, the researchers estimate. Related animals didn’t become that big again until the Eocene, 150 million years later. “We think it’s one of the most unexpected fossil discoveries from the Triassic of Europe,” says study coauthor Grzegorz Niedzwiedzki, a paleontologist at Uppsala University in Sweden. “Who would have ever thought that there is a fossil record of such a giant, elephant-sized mammal cousin in this part of the world?” He and his team first described some of the bones in 2008; now they’ve made the new species — Lisowicia bojani — official.
The creature had upright forelimbs like today’s rhinoceroses and hippos, instead of the splayed front limbs seen on other Triassic dicynodonts, which were similar to the forelimbs of present-day lizards. That posture would have helped it support its massive bodyweight.
A new design for sun-powered desalination technology may lead to longer-lasting devices that produce cleaner water.
The trick boils down to preventing a device’s components from touching the saltwater. Instead, a lid of light-absorbing material rests above a partially filled basin of water, absorbing sunlight and radiating that energy to the liquid below. That evaporates the water to create pure vapor, which can be condensed into freshwater to help meet the demands of a world where billions of people lack safe drinking water (SN: 8/18/18, p. 14). This setup marks an improvement over other sun-powered desalination devices, where sunshine-absorbing materials float atop the saltwater (SN: 8/20/16, p. 22). In those devices, salt and other contaminants left behind during evaporation can degrade the material’s ability to soak up sunlight. Having water in contact with the material also prevents the material from getting hotter than about 100° Celsius or producing steam above that temperature. That limits the technology’s ability to purify the final product; killing pathogenic microbes often requires temperatures of at least 121° C.
In the new device, described online December 11 in Nature Communications, the separation between the light-absorbing lid and the water’s surface helps keep the lid clean and allows it to generate vapor tens of degrees hotter than the water’s boiling point.
The lid comprises three main components: a top layer made of a metal-ceramic composite that absorbs sunshine, a sheet of carbon foam and a bottom layer of aluminum. Heat spreads from the sunlight-absorbing layer to the aluminum, from which thermal energy radiates to the water below. When the water temperature hits about 100° C, vapor is produced. The steam rises up through holes in the aluminum and flows through the lid’s middle carbon layer, heating further along the way, until it is released in a single stream out the side of the lid. There, it can be captured and condensed.
Producing superheated steam in this way, without any gunk buildup, is “a very innovative idea,” says Jia Zhu, a materials scientist at Nanjing University in China not involved in the work. Under a lamp that mimics natural sunlight in the lab, the device evaporated 100 grams of saltwater without any salt collecting on the underside of the lid. Salt crystals formed at the bottom of the basin washed away easily. In experiments in October on a rooftop in Cambridge, Mass., researchers used a curved mirror to focus incoming sunlight onto the light-absorbing layer of the device to produce steam hotter than 146° C.
“When you can access these temperatures, you can use the steam for things like sterilization, for cooking, for cleaning, for industrial processes,” says coauthor Thomas Cooper, a mechanical engineer at York University in Toronto. A device measuring 1 square meter could generate 2.5 liters of freshwater per day in sunny regions such as the southeastern United States, and at least half that in shadier regions such as New England, Cooper estimates.
This sun-powered technology could also provide an ecofriendly alternative to reverse osmosis, a water purification process that involves pushing seawater through salt-filtering membranes (SN: 9/15/18, p. 10). Reverse osmosis, which runs on electricity, “is an energy-hungry technology,” says Qiaoqiang Gan, an engineer at the University at Buffalo in New York not involved in the work. “For resource-limited areas, remote areas or people who live on small islands, this [new device] might be a very good option for them to address their freshwater needs.” But researchers still need to investigate how affordable a commercial version of this device would be, Gan says.
SAN DIEGO — Labs growing replicas of snakes’ venom glands may one day replace snake farms.
Researchers in the Netherlands have succeeded in growing mimics of venom-producing glands from multiple species of snakes. Stem cell biologist Hans Clevers of the Hubrecht Institute in Utrecht, the Netherlands, reported the creation of these organoids on December 10 at a joint meeting of the American Society for Cell Biology and the European Molecular Biology Organization.
If scientists can extract venom from the lab-grown glands, that venom might be used to create new drugs and antidotes for bites including from snakes that aren’t currently raised on farms.
Up to 2.7 million people worldwide are estimated to be bitten by venomous snakes each year. Between about 81,000 to 138,000 people die as a result of the bite, and as many as roughly 400,000 may lose limbs or have other disabilities, according to the World Health Organization. Antivenoms are made using venom collected from snakes usually raised on farms. Venom is injected into other animals that make antibodies to the toxins. Purified versions of those antibodies can help a bitten person recover, but must be specific to the species of snake that made the bite. “If it’s a fairly rare or local snake, chances are there would be no antidote,” Clevers says.
Three postdoctoral researchers in Clevers’ lab wanted to know if they could make organoids — tissues grown from stem cells to have properties of the organs they mimic — from snakes and other nonmammalian species. The researchers started with Cape coral snakes (Aspidelaps lubricus) that were dissected from eggs just before hatching. Stem cells taken from the unhatched snakes grew into several different types of organoids, including some that make venom closely resembling the snake’s normal venom, Clevers reported at the meeting.
His team has produced venom-gland organoids from at least seven species of snakes. The organoids have survived in the lab for up to two years so far.
Clevers and colleagues hope to harvest venom from the organoids, which produce more highly concentrated venom than snakes usually make. “It’s probably going to be easier than milking a snake,” he says.
WASHINGTON — After a stunningly explosive summer, Kilauea, the world’s longest continuously erupting volcano, finally seems to have taken a break. But the scientists studying it haven’t. Reams of new data collected during an unprecedented opportunity to monitor an ongoing, accessible eruption are changing what’s known about how some volcanoes behave.
“It was hugely significant,” says Jessica Larsen, a petrologist at the University of Alaska Fairbanks, and “a departure from what Kilauea had been doing for more than 35 years.” The latest eruption started in May. By the time it had ended three months later, over 825 million cubic meters of earth had collapsed at the summit. That’s the equivalent of 300,000 Olympic-sized swimming pools, Kyle Anderson, a geophysicist with the U.S. Geologic Survey in Menlo Park, Calif., said December 11 in a news conference at the annual meeting of the American Geophysical Union.
As the summit crater deflated, magma gushed through underground tunnels, draining out through fissures along an area called the lower eastern rift zone at a rate of roughly 50 meters per day. That lava eventually covered 35.5 square kilometers of land, Anderson and his colleagues reported in a study published December 11 in Science.
The volcano also taught scientists a thing or two. Scientists previously believed that groundwater plays a big role in how a caldera collapses. When craters were drained of their magma, “cooling, cracking depressurized the caldera, allowing groundwater to seep in and create a series of explosive eruptions,” Anderson said. “But groundwater did not play a significant role in driving the explosions this summer.”
Instead, the destruction of Kilauea’s crater is what’s called a piston-style caldera collapse, he said. Sixty-two small collapse events rattled the volcano from mid-May to late August, with each collapse causing the crater to sink and pushing the surrounding land out and up. By the end, the center of the volcano sank by as much as 500 meters — more than the height of the Empire State Building.
That activity didn’t just destroy the crater. “We could see surges in the eruption rate 40 kilometers away whenever there was a collapse,” Anderson said. Life finds a way Under the sea, life moved in around the brand-new land surprisingly quickly. Using a remotely operated vehicle to explore the seafloor, researchers in September found evidence of hydrothermal activity along newly deposited lava flows about 650 meters deep. More surprising, bright yellow, potentially iron-oxidizing microbes had already moved in.
“There’s no reason why we should have expected there would be hydrothermal activity that would be alive within the first 100 days,” Chris German, a geologist at Woods Hole Oceanographic Institution in Falmouth, Mass., said at the news conference. “This is actually life here!”
The discovery suggests “how volcanism can give rise to the chemical energy that can drive primitive microbial organisms and flower a whole ecosystem,” he said.
Studying these ecosystems can provide insight into how life may form in places like Enceladus, an icy moon of Saturn. Hydrothermal activity is common where Earth’s tectonic plates meet. But alien worlds don’t show evidence of plate tectonics, though they can be volcanically active, German says. Studying how hydrothermal life forms near volcanoes that aren’t along tectonic boundaries on Earth could reveal a lot about other celestial bodies.
“This is a better analog of what we expect to them to be like,” says German, but “it is what’s least studied.”
What comes next As of December 5, Kilauea had not erupted for three months, suggesting it’s in what’s called a pause – still active but not spewing lava. Observations from previous eruptions suggest that the next phase of Kilauea’s volcanic cycle may be a quieter one. But the volcano likely won’t stay quiet forever, says Christina Neal, the head scientist at the USGS Hawaiian Volcano Observatory and a coauthor of the Science paper. “We’re in this lull and we just don’t know what is going to happen next,” she says.Life finds a way Under the sea, life moved in around the brand-new land surprisingly quickly. Using a remotely operated vehicle to explore the seafloor, researchers in September found evidence of hydrothermal activity along newly deposited lava flows about 650 meters deep. More surprising, bright yellow, potentially iron-oxidizing microbes had already moved in.
“There’s no reason why we should have expected there would be hydrothermal activity that would be alive within the first 100 days,” Chris German, a geologist at Woods Hole Oceanographic Institution in Falmouth, Mass., said at the news conference. “This is actually life here!”
The discovery suggests “how volcanism can give rise to the chemical energy that can drive primitive microbial organisms and flower a whole ecosystem,” he said.
Studying these ecosystems can provide insight into how life may form in places like Enceladus, an icy moon of Saturn. Hydrothermal activity is common where Earth’s tectonic plates meet. But alien worlds don’t show evidence of plate tectonics, though they can be volcanically active, German says. Studying how hydrothermal life forms near volcanoes that aren’t along tectonic boundaries on Earth could reveal a lot about other celestial bodies. Scientists are tracking ground swelling near the Puu Oo vent, where much of Kilauea’s lava has flowed from during the volcano’s 35-year eruption history. That inflation is an indication that magma may still be on the move deep below.
The terrain surrounding this remote region is dense with vegetation, making it a difficult area to study. But new methods tested during the 2018 eruption, such as the use of uncrewed aerial vehicles, for example, could aid in tracking the recent deformation.
Scientists are also watching the volcano next door: Mauna Loa. History has shown that Mauna Loa can act up during periods when Kilauea sleeps. For the past several years, volcanologists have kept an eye on Kilauea’s larger sister volcano, which went silent last fall, after a period with few earthquakes and intermittent deformation. “We’re seeing a little bit of inflation at Mauna Loa and some earthquake swarms where it had been active, Neal says. “So that’s another issue of concern for us going into the future.”
