Astronomers may have spotted some of the earliest stardust ever created in the cosmos.
Astrophysicist Nicolas Laporte of University College London and colleagues detected the dust in a galaxy seen as it was when the universe was only 600 million years old. “We are probably seeing the first stardust of the universe,” Laporte says. The observations, published online March 8 in the Astrophysical Journal Letters, could help astronomers learn more about an early period known as cosmic reionization, when ultraviolet radiation stripped electrons from hydrogen atoms. “Dust is ubiquitous in nearby and more distant galaxies, but has, until recently, been very difficult to detect in the very early universe,” says University of Edinburgh astrophysicist Michal Michalowski, who was not involved in the study. “This paper presents the most distant galaxy for which dust has been detected.”
The galaxy, called A2744_YD4, lies behind a galaxy cluster called Abell 2744. That cluster acts as a gravitational lens, magnifying and brightening the distant galaxy’s light by about a factor of two. Laporte and colleagues observed the galaxy with ALMA, the Atacama Large Millimeter/submillimeter Array in Chile, which revealed the dust. Dust in such a remote galaxy comes from supernova explosions of massive stars that were among the earliest stars in the universe. Astronomers estimate the first stars formed around 400 million years after the Big Bang, which occurred 13.8 billion years ago. Laporte and colleagues estimate that A2744_YD4’s dust, at 600 million years after the Big Bang, weighs in at about 6 million times the mass of the sun. “This means that supernova explosions are able to produce large amounts of dust very quickly,” Michalowski says. Laporte and colleagues also detected positively charged, or ionized, oxygen atoms and a signature of hydrogen, which suggest the galaxy’s gas is ionized. Cosmic reionization completely rebooted the universe so that ionized rather than neutral atoms pervaded space. Understanding this switch from neutral to ionized atoms gives clues to how stars and galaxies arose in the early universe. Finding ionized oxygen in such a remote galaxy “provides evidence that at least a fraction of cosmic reionization was caused by galaxies like A2744_YD4,” Michalowski says.
Until now, astronomers have been charting the early history of galaxies by counting them and looking at their colors, notes study coauthor Richard Ellis, a cosmologist currently on leave from University College London at the European Southern Observatory. Spotting dust in the distant universe offers a new route to determine when the earliest galaxies first formed, based on the abundances of oxygen, silicon and other heavier elements that they contain. Fewer heavy elements would point to younger and younger galaxies.
The detection of ionized oxygen could also hint that a black hole lurks at the center of A2744_YD4. Ionized oxygen, seen by the signal it emits in millimeter wavelengths, may be difficult to generate from young hot stars alone. Another strong source of ionizing radiation, such as a black hole, may be needed to account for the signature. “Unfortunately with only one emission line we cannot, for sure, claim there’s a black hole in A2744_YD4,” Ellis says.
Sea ice skylights formed by warming Arctic temperatures increasingly allow enough sunlight into the waters below to spur phytoplankton blooms, new research suggests. Such conditions, probably a rarity more than two decades ago, now extend to roughly 30 percent of the ice-covered Arctic Ocean during July, researchers report March 29 in Science Advances.
The microscopic critters need plenty of sunlight to thrive, so scientists were stunned by the discovery of a sprawling bloom below the normally sun-blocking Arctic ice in July 2011 (SN: 7/28/12, p. 17). Satellites can’t peek below the ice, though, so scientists at the time didn’t know whether the bloom was an oddity or representative of a shift in the Arctic environment.
Harvard University oceanographer Christopher Horvat and colleagues created a computer simulation of sea ice conditions from 1986 through 2015. Warming temperatures have thinned the ice, the researchers found, and increased the prevalence of meltwater pools on top of the ice that allow more light to pass through than bare or snow-covered ice.
Whether blooms are in fact more commonplace under the ice remains unclear, though, because the study didn’t consider whether there would be enough nutrients such as nitrogen and iron for budding blooms. If more blooms are lurking in the Arctic Ocean, they may already be dramatically reshaping the Arctic ecosystem. A boost in phytoplankton could alter marine food webs as well as soak up more planet-warming carbon dioxide from the environment.
Big bloom Increasingly large swaths of the ice-covered Arctic Ocean allow enough light into the waters below to support phytoplankton blooms, new research suggests. Green regions indicate bloom-friendly conditions in July over the last few decades, with darker shades representing longer duration.
Gravel devil GRAV-uhl DEV-uhl n. A whirlwind containing gravel-sized debris
Towering, crystal-filled twisters periodically swirl in a valley nestled between two volcanoes in the Andes Mountains, newly reported observations show. The odd weather events are the first record of large pieces of gravel efficiently moving across a landscape by suspension in air.
Geologist Kathleen Benison of West Virginia University in Morgantown spotted the whirlwinds during an expedition in 2007 to an otherworldly region of northern Chile. There, gypsum crystals form from evaporating volcanic pools of salty, acidic water. When the pools dry, exposing the crystals within, whirlwinds as big as half a kilometer across can sweep the crystals aloft, Benison reports online March 15 in Geology. She saw storms of crystals travel as far as five kilometers before dropping their payloads into large, dunelike piles. Over time the far-flung crystals, some as long as 27 centimeters (which geologists still classify as gravel), meld together into a massive hunk. If found in the rock record, such crystal conglomerations could help geologists identify where strong whirlwinds howled long ago, Benison proposes.
Continental drift, a theory often considered amusing but rarely important, seems about to become the focus of a revolution in geology. At the least, it has already split the geological community into those who find the evidence for it “formidable” and those who think it is not yet formidable enough to constitute a proof. — Science News, April 29, 1967
Update That continents shift is now widely accepted and explained by plate tectonics. Plenty of evidence supports the idea that the Earth’s outer layer is divided into large slabs that gradually move over the mantle. But researchers don’t agree on when the plates first began shifting. New evidence from ancient rocks found in Canada suggests the slipping and sliding didn’t get going until Earth was at least a billion years old (SN: 4/15/17, p. 8). In about 250 million years from now, the continents may drift together into a supercontinent called Amasia (SN: 1/21/17, p. 18).
Groundwater that has lingered in Earth’s depths for more than 12,000 years is surprisingly vulnerable to modern pollution from human activities. Once in place, that pollution could stick around for thousands of years, researchers report online April 25 in Nature Geoscience. Scientists previously assumed such deep waters were largely immune to contamination from the surface.
“We can’t just drill deep and expect to run away from contaminants on the land surface,” says Scott Jasechko, a study coauthor and water resources scientist at the University of Calgary in Canada. Groundwater quenches the thirst of billions of people worldwide and accounts for roughly 40 percent of the water used in agriculture. Water percolating from the surface into underground aquifers can carry pollutants such as pesticides and salt along for the ride.
Jasechko and colleagues weren’t looking for contamination when they tested water from 6,455 water wells around the world. Their goal was to use carbon dating to identify how much of that deep water was “fossil” groundwater formed more than 12,000 years ago. Previous studies had looked at average water age, rather than the age of its individual components.
While there’s no C in H2O, carbon dating can still be used to date groundwater by examining the carbon dissolved in the water. Radioactive carbon atoms decay as the water ages. After around 12,000 years, only stable carbon isotopes remain. Comparing the relative abundance of these carbon isotopes in the various wells, the researchers discovered that over half of wells more than 250 meters deep yielded mostly groundwater at least 12,000 years old. How much older is unknown. Worldwide, the researchers estimate that fossil groundwater accounts for 42 to 85 percent of water in the top kilometer of Earth’s crust. In a second measurement, the researchers looked for a common modern pollutant. They found that around half of wells containing mostly fossil groundwater had elevated traces of tritium, a radioactive hydrogen isotope spread during nuclear bomb tests that’s hazardous in very high concentrations. While the tritium levels weren’t dangerous, its presence suggests that at least some groundwater in the wells postdates the 1950s nuclear testing. That relatively young water may introduce other contaminants in addition to tritium, the researchers say. How new groundwater enters deep wells is still unclear, Jasechko says. Old and young waters could mix within an aquifer or, alternatively, the construction and use of the well itself could churn the waters together.
No matter where the young water comes from, the new technique for identifying the percentage of fossil groundwater in a well could be an important tool for communities, says Audrey Sawyer, a hydrogeologist at Ohio State University in Columbus. The study raises awareness that even in wells with mostly older water “a fraction of that same water can be pretty young and susceptible to contamination,” she says.
COLD SPRING HARBOR, N.Y. — When breast cancer spreads, it moves in gangs of ready-to-rumble tumor cells, a small genetic study suggests. Most of the mutations that drive recurrent tumors when they pop up elsewhere in the body were present in the original tumor, geneticist Elaine Mardis reported May 9 at the Biology of Genomes meeting.
For many types of cancer, it is the spread, or metastasis, of tumor cells that kills people. Because cancer that comes back and spreads after initial treatment is often deadlier than the original tumors, researchers thought most of the mutations in recurrent tumors happened after they spread. But the new findings contradict this assumption and may indicate ways to stop metastasis. Mardis, of Nationwide Children’s Hospital in Columbus, Ohio, and colleagues collected recurrent breast tumors from 16 women who died after their cancer had spread to other parts of the body. Comparing the metastasized tumors with the original breast tumors, the researchers were surprised to learn that multiple, slightly genetically different cells from the original site had broken away together and established the new tumors.
Researchers used to think cancer spread when single cells slipped away and set up shop elsewhere. But recent research in mice suggested cancer cells migrate in groups (SN: 1/10/15, p. 9). The new study doesn’t provide direct evidence of this group migration in human cancer. But genetic similarities between metastasized and original tumors suggest that multiple cells move together to remote sites.
Only two women in the study had cancer-driving mutations — both in an estrogen receptor gene called ESR1 — in their recurrent tumors not seen in the original. All of the tumors that metastasized contained mutations in the TP53 gene. Such mutations could be a warning sign that a breast cancer is prone to spread, Mardis said.
When astronomers in February announced the discovery of seven planets orbiting a supercool star, details about the outermost planet were sketchy. No more. The seventh planet is chilly and definitely no place for life, the international team reports May 22 in Nature Astronomy.
The seven-planet system, TRAPPIST-1, is 39 light-years from Earth in the constellation Aquarius. Follow-up observations of the system reveal that TRAPPIST-1h is about three-quarters the size of Earth and orbits its star in just under 19 days. The planet sits about 9.6 million kilometers from its star, which has only 8 percent of the mass of the sun. As a result, TRAPPIST-1h gets about as much starlight as the icy dwarf planet Ceres, in the asteroid belt, gets from the sun.
Such limited light makes the planet too cold (‒100° Celsius) to harbor liquid water and therefore life as we know it, the researchers report.
Tornadoes in the southeast, Earth’s magnetic field and obesity might not seem to have much in common. Well, now they do.
Under President Donald Trump’s 2018 budget proposal, federal research spending into all three areas — and many others — would decline abruptly. The president delivered his budget request to Congress on May 23, presenting the sharpest picture yet of his administration’s priorities for federal science spending. Some science and technology programs within agencies would see their funds increase, but the administration recommends extensive cuts to basic research overall. The request greatly expands on the “skinny budget” the administration released in March (SN: 4/15/17, p. 15).
Total federal research spending would be slashed by about 17 percent, Rush Holt, CEO of the American Association for the Advancement of Science, said in a conference call with reporters. “If the White House budget plan were to become law, it would devastate America’s science and technology enterprise.”
For many science agencies and programs, the outlook appears stark. Some examples:
The National Science Foundation, which funds research in all fields of science and engineering, would face an 11 percent cut. The U.S. Geological Survey’s budget would be cut by 15 percent. The National Institute of Standards and Technology, where research includes cybersecurity and nanotechnology, would face a 23 percent cut. The National Oceanic and Atmospheric Administration’s primary research arm, which investigates weather, climate and ocean resources, would be cut 32 percent. The Environmental Protection Agency’s Office of Science & Technology would be cut by 37 percent. The budget proposes a 16 percent cut for the Department of Energy’s Office of Science, the largest supporter of basic research in the physical sciences. The U.S. Centers for Disease Control and Prevention would take a 17 percent cut. Food and Drug Administration funding (not including revenue from user fees) would be cut by 30 percent. The U.S. Department of Agriculture’s Agricultural Research Service would fall 22 percent. And, as expected, the National Institutes of Health’s budget would be slashed 22 percent. Those numbers don’t mean much just yet — they are just a starting point for a long and winding route through the political process. But the details do provide more information about what programs and areas of research could be in trouble. NSF’s grant programs, for example, would lose $776 million, dropping the overall budget from $7.5 billion to $6.65 billion. As a result, the agency estimates that in fiscal year 2018, the proposed funds would support about 8,000 new research grant awards, about 800 fewer than in 2016. Among the NSF-funded programs facing potentially severe reductions are clean energy research and development and the Ocean Observatories Initiative, an array of marine and seismic sensors scattered across the Atlantic and Pacific oceans that is expected to provide some of the most detailed ocean measurements to date (SN: 10/19/13, p. 22). The project would see its NSF funding slashed by 44 percent.
A bright spot: The request leaves funding flat for LIGO, which discovered gravitational waves in 2016 (SN: 3/5/16, p. 6). Planned, continued upgrades to the project’s laser interferometer systems are still on, NSF director France Córdova said May 23 at a budget presentation at NSF headquarters in Arlington, Va. NSF has invested about $1.1 billion in the project. “It was the biggest investment NSF has made to date, and it was a big risk,” Córdova said.
Many in the scientific community say the proposed cuts would significantly undermine the nation’s global leadership role in advancing science. And they doubt the administration’s argument that the private sector would make the necessary investments in basic science research.
“Candidly, shareholders are not interested in funding research, which tends to be costly, very long-term and very risky,” said retired aerospace executive Norman Augustine during the AAAS conference call. “Research is a public good.… The rewards tend to go to the public as a whole, and therefore research really warrants government support.”
Funding for DOE’s energy programs, including research into efficiency and renewable energy, would fall about 60 percent. One of those programs, the Advanced Research Projects Agency-Energy, would be eliminated. The administration defends phasing out the roughly $300 million ARPA-E, which funds research on risky but promising energy technologies, by saying the private sector is “better positioned” to finance such research.
Within the DOE Office of Science, the biological and environmental research program, which studies climate modeling among other things, faces the steepest cut — 43 percent, a drop from $612 million to $349 million. High-energy physics research would see an 18 percent reduction, but the program for advanced scientific computing would get an 11 percent bump.
Environmental research would suffer at NOAA, with the Office of Oceanic and Atmospheric Research facing sweeping cuts. Funding for climate research would drop 19 percent, weather and air chemistry research 25 percent and ocean, coastal and Great Lakes research by 49 percent. Programs potentially shuttered include:
Air Resources Laboratory, which researches air chemistry, mercury deposition and the movement of harmful materials through the atmosphere. VORTEX-Southeast, a tornado detection and warning program for the southeastern United States. The Marine Mammal Commission, an independent agency formed in 1972 to help protect marine animals and their habitats. At USGS, the roughly $1.9 million geomagnetism program would be zeroed out. It monitors changes in Earth’s magnetic field, providing data that help NOAA and the U.S. Air Force track magnetic storms due to solar activity. Such storms can disrupt radio communication, GPS systems and, if severe enough, the electric power grid. The agency’s Climate and Land Use Change program, renamed the Land Resources program, would see a 24 percent cut. Most of the funding for a carbon sequestration research program, about $8 million, would be eliminated, with the rest, about $1.5 million, being redirected to the energy and minerals program. That division would see about a 2 percent increase overall.
Health programs and biomedical research would face big challenges under Trump’s budget. At CDC, $1.2 billion would be slashed from the agency’s overall budget. The request proposes cutting $163 million from the agency’s chronic disease prevention programs, which aim to reduce incidence of heart disease, stroke, diabetes and obesity. Prevention programs for domestic HIV/AIDS, sexually transmitted diseases and tuberculosis face a $183 million decrease in funding.
NIH’s overall budget would fall from the enacted 2017 level of $34.6 billion to $26.9 billion. Some of the most striking cuts:
National Cancer Institute — $1.2 billion National Heart, Lung and Blood Institute — $672 million. National Institute of Allergy and Infectious Diseases — $1.1 billion. National Institute of Diabetes and Digestive and Kidney Diseases — $421 million. Congress, however, recently boosted NIH funding — at least for fiscal year 2017 — providing an additional $2 billion over the next five months.
That’s an important reminder that many of the programs facing extensive reductions or elimination have allies on Capitol Hill, a potentially comforting thought for those alarmed by the president’s request. “We’re counting on Congress to, once again, say no to these recommendations,” Mary Woolley, president of the health and medical research advocacy group Research!America, said in the AAAS conference call.
Not all science agencies or programs are threatened. For instance, NASA’s planetary science division would see a funding bump. The final 2017 spending agreement, which Congress recently passed, had already increased the division’s budget from $1.63 billion to $1.85 billion. In Trump’s proposal, that number is nudged even higher, to $1.93 billion. As expected, the administration supports a flyby mission to Europa, one of Jupiter’s moons. The president has requested $425 million for the project, a 55 percent increase from the 2017 enacted level of $275 million.
“We’re pleased by our top-line number of $19.1 billion, which reflects the president’s confidence in our direction and the importance of everything we’ve been achieving,” said NASA acting administrator Robert Lightfoot.
But the agency would lose about 9 percent of its earth science budget, slightly more than expected. Grants for earth science research would be cut, and NASA’s Carbon Monitoring System, which Congress directed the space agency to form in 2010, would be axed. Five space-based earth science projects would also be eliminated. Those projects are meant, in part, to provide data to help understand various aspects of Earth’s climate and how it is changing.
Trump’s budget proposal will not get passed by Congress unchanged. Still, the administration’s lack of support for basic federal research overall has alarmed many scientists and their supporters.
“Science research has been the source of improvements in public health, in our energy, in our quality of life, in our agriculture and ability to feed ourselves and the world,” said Holt. “What we see is not just a reduction in government programs. What we see is a failure to invest in America.”
Zuul is back. But don’t bother calling the Ghostbusters. Zuul crurivastator is a dino, not a demon. A 75-million-year-old skeleton unearthed in Montana in 2014 reveals a tanklike dinosaur with a spiked club tail and a face that probably looked a lot like its cinematic namesake.
The find is the most complete fossil of an ankylosaur, a type of armored dinosaur, found in North America, researchers report May 10 in Royal Society Open Science. It includes a complete skull and tail club, plus some preserved soft tissue, says study co-author Victoria Arbour, a paleobiologist at the Royal Ontario Museum in Toronto. “It really gives us a good idea of what these animals looked like.” The bones reveal that Z. crurivastator had spikes running all the way down its tail, not just on the club itself. That arrangement means the weaponry was more than just a “massive sledgehammer,” Arbour says. The club was a formidable weapon. The term crurivastator comes from the Latin for “shin destroyer.” Arbour previously created mathematical models to calculate the force with which similar ankylosaurs might have swung their tails. These appendages provided a winning combination: good at absorbing impacts and able to smack an opponent hard enough to hurt, she says. Despite their armor and fearsome tail, ankylosaurs were plant eaters. So they probably used their tails to smack predators or compete with other ankylosaurs.
Arbour and museum colleague David Evans plan to investigate the thin sheet of fingernail-like material covering the bony plates on the tail, along with other details of the fossil that are typically lost in such old specimens. The rare, preserved soft tissue might even let scientists extract ancient proteins, Arbour says, providing insight into how these building blocks of life have changed since the days of dinos.
Having all this material in hand, she says, “kind of pushes the envelope about what we can identify in the fossil record.”
People with weakened immune systems might help scientists get a jump on the flu virus.
Some flu virus mutations popped up again and again in cancer patients with long-term infections, researchers report June 27 in eLife. And some of those mutations were the same as ones found in flu viruses circulating around the world a few years later, evolutionary virologist Jesse Bloom of the Fred Hutchinson Cancer Research Center in Seattle and colleagues discovered. The findings may eventually help vaccine developers predict flu strain evolution. “You can’t predict what’s going to happen next year,” — at least not yet, Bloom says. But monitoring infections in many people may indicate which parts of the virus are most likely to change in the future.
Most people who catch the flu get over it in about a week. Previous studies have suggested that the virus doesn’t change much within one person. It must pass through tens to hundreds of people to build up enough mutations to give it an advantage over other flu viruses, Bloom says. That makes predicting flu evolution tricky.
A coffee shop conversation alerted Bloom to a potential treasure: multiple nasal wash samples from four cancer patients who had had the flu for months in 2006 and 2007. Part of their cancer treatments had weakened all four people’s immune systems, making it hard for them to fight off the infections.
Evolutionary biologist Katherine Xue in Bloom’s lab and colleagues examined genetic material from the nasal washes, identifying mutations present in at least 5 percent of flu viruses in each person. The team tracked competition between virus variants within each person over time and compared virus evolution patterns among the patients.
Nine flu mutations popped up in at least two separate patients. Of those, five were in the virus’s hemagglutinin gene. That gene encodes a sugar-studded protein on the virus’s outer surface that helps the virus stick to and invade human cells. The immune system commonly makes antibodies against hemagglutinin that foil the strain’s ability to infect the host again. As a result, the virus has to mutate so that the protein will be different enough to evade the immune system. Four amino acids of the hemagglutinin protein were frequently changed by mutations in the cancer patients’ viruses and popped up years later in flu strains worldwide, too. Those amino acids are the 138th, 193rd, 223rd and 225th links in the chain of amino acids that make up the hemagglutinin protein.
In some cases, the mutations produced the same amino acid change in both the cancer patients’ and the global virus strains circulating after 2010. For instance, the amino acid valine was altered to isoleucine at position 223. That happened in two cancer patients in 2006 and 2007. After about 2012, nearly all viruses circulating worldwide had the same change.
In another case, those same two cancer patients’ viruses had tyrosine at position 193, but globally circulating viruses had either phenylalanine or serine at that position, the researchers found. Those results indicate that at some spots in the protein, particular changes are important, but other positions are more malleable.
Within patients, viruses carrying different amino acids seemed to directly compete against each other; as one became more frequent, the other was reduced in abundance. That’s the same sort of pattern researchers observe at the global level. Knowing which mutations commonly win competitions in immune-compromised patients may give a preview of winners in the global flu fight.
Not all of the flu mutations that arose in the cancer patients were later found in the general population, says infectious disease biologist Katia Koelle of Duke University. For instance, a mutation called L427F (changing leucine at position 427 to phenylalanine) was found in more than 75 percent of flu viruses in three of the cancer patients, but it was never seen in flu viruses circulating globally. That mutation might give flu viruses some advantage within a person, but might not be efficient at spreading from person-to-person, Koelle says. Studies that compare flu alterations in multiple people won’t immediately tell researchers how to design vaccines, she says, but could point to parts of the virus for further investigation.
Xue and Bloom say they would like to repeat the study, perhaps this time in very young children and elderly people — two groups that also have weaker immune systems than most adults.
