The beard now feared! Visiting NBA superstar James Harden got a taste of Chinese speed with his jaw on the floor, as he sold out 10,000 bottles from his J-HARDEN brand wine within seconds during a live commerce on Tuesday night.
Harden showed up in the Chinese online celebrity CrazyXiaoyangge's livestreaming channel on Tuesday night with his personal brand J-Harden wine. Within seconds, Harden was told that 5,000 orders (436 yuan or $60 for two bottles) had been placed, meaning his 10,000 bottles were sold out at lightning speed. More than 15 million people watched the Harden live stream on Tuesday night.
Finding the China speed unbelievable, Harden shouted with excitement "no way!" Harden had to go to the computer to confirm the sales record.
Harden then added another 3,000 orders and again they were sold out within seconds.
Feeling so pumped, the NBA super star even performed a side cartwheel.
Chinese basketball fans showed much support to Harden during the livestreaming, leaving "MVP" comments all over the live stream .
Harden, in return, learned to say "woaini" - "I love you" in Chinese, to his fans during the livestreaming. And discussion on James Harden being amazed by China speed during the live commercial became trending topic on China's twitter-like Sina Weibo on Wednesday morning.
Diehard Harden fans even suggested that if the NBA star is not happy in the American basketball league, he is welcomed to joint Team China and become an influencer on the Chinese internet.
Harden, although completing a season that failed to meet expectations with Philadelphia 76ers, received broad support from Chinese fans during China summer tour, especially after he lashed out at the team's president Daryl Morey as "a liar" during a commercial event in Beijing on Monday.
"Daryl Morey is a liar and I will never be a part of an organization that he's a part of," "Let me say that again: Daryl Morey is a liar and I will never be a part of an organization that he's a part of," he said.
In October 2019, Morey then the GM for the Houston Rockets posted on Twitter a slogan used by Hong Kong rioters at the time.
He quickly drew the ire of the Chinese people and the team's Chinese fans and also triggered a backlash from business partners, including a more-than-one-year long suspension of NBA games on China Central Television (CCTV).
Just how fantastical a planet can be and still support recognizable life isn’t just a question for science fiction. Astronomers are searching the stars for otherworldly inhabitants, and they need a road map. Which planets are most likely to harbor life? That’s where geoscientists’ imaginations come in. Applying their knowledge of how our world works and what allows life to flourish, they are envisioning what kind of other planetary configurations could sustain thriving biospheres.
You don’t necessarily need an Earth-like planet to support Earth-like life, new research suggests. For decades, thinking about the best way to search for extraterrestrials has centered on a “Goldilocks” zone where temperatures are “just right” for liquid water, a key ingredient for life, to wet the surface of an Earth doppelgänger. But now it’s time to think outside the Goldilocks zone, some scientists say. Unearthly mechanisms could keep greenhouse gas levels in check and warm planets in the coldest outer reaches of a solar system. Life itself could even play a starring role in a planet’s enduring habitability. “It’s an exciting time,” says Harvard planetary scientist Robin Wordsworth. “There’s still a ton for us to learn about the way different planets behave. The Goldilocks zone is just a very rough guide, and we need to keep an open mind.”
Currency of life When it comes to habitable planets, water continues to be the currency of life. Too close to a star and all the water on a planet evaporates; too far and the planet is an icy snowball. The Goldilocks zone marks the region between those two extremes, where water can stay liquid. Every known organism requires liquid water at some point during its life cycle. Extraterrestrial life could be completely unlike anything seen on Earth, of course, but “we’ve got to start looking somewhere,” says Colin Goldblatt, a planetary scientist at the University of Victoria in Canada. “At least we know what Earth life looks like.” With the assumption that water is king, astronomers search for wet planets using powerful telescopes. The search is limited by what the telescopes can see in a planet’s atmosphere, however. Life-supporting liquid water could hide under the surface, for example, inside Jupiter’s icy moon Europa (SN: 10/4/14, p. 10). And any subterranean life, which typically wouldn’t alter the atmosphere, would probably be undetectable. Even with rovers roaming Mars, scientists can’t tell for certain whether Martian groundwater hosts life (SN: 12/26/15, p. 26). For alien life to be observable from afar, liquid water would have to be at the surface, not just concealed belowground.
With liquid surface water as a must-have for hunting extraterrestrials, astronomers estimated the extent of the habitable region more than 50 years ago. Early research confined the Goldilocks zone for our own solar system to a narrow band — one estimate placed it from 0.95 times to 1.01 times Earth’s average distance from the sun. But then scientists realized the surprising influence of Earth’s built-in temperature control system: the carbon cycle, the process by which carbon travels from the atmosphere into the Earth and back out to the atmosphere.
The carbon cycle controls how much heat-trapping carbon dioxide is in the atmosphere. Rainfall weathers exposed rocks, causing a chemical reaction that pulls CO2 from the air and into the oceans and eventually underground via plate tectonics. Volcanoes, meanwhile, spew CO2 into the atmosphere. This cycle keeps the planet’s temperatures from getting too extreme.
If the climate ever gets too cold, the carbon cycle could boost CO2 to compensate. For instance, if temperatures drop and rainfall slows, the lack of weathering will allow CO2 to build up in the atmosphere. And as volcanoes continue belching up additional CO2, temperatures will rise and rainfall will rise. And if things get so hot that glaciers melt and rainfall increases, the planet will cool as weathering accelerates and draws down more CO2 from the atmosphere. Plants and other organisms also play roles in drawing in CO2 or releasing it into the air.
This balancing act could help keep planets within a comfortable range for life, expanding the habitable zone to as wide as 0.5 to 2.0 times Earth’s distance from the sun, though these numbers are hotly contested. Thanks to the carbon cycle, Earth might still be habitable even if pushed out to Mars’ orbit, says Penn State geoscientist James Kasting.
Rocky recycling Not every planet tucked safely inside the habitable zone is necessarily life-friendly. Venus and Mars are within the habitable zone by some definitions, but neither boasts a livable surface climate. More than location is at play. Other factors such as plate tectonics may make a planet right or wrong for life. Plate tectonics is an important piece in the temperature-controlling carbon cycle, as the shifting and sinking plates that cover Earth’s surface carry carbon into Earth’s interior that later erupts from volcanoes. Some scientists propose that planets akin to Venus and Mars that lack the conditions for plate tectonics should be crossed off the “explore list” (SN: 1/23/16, p. 8). Lindy Elkins-Tanton, a planetary scientist at Arizona State University in Tempe, disagrees. On exoplanets, other processes could do the job of plate tectonics, she said last December at an American Geophysical Union meeting in San Francisco. “We’re too Earth-centric in our notion of how you can create a planetary carbon cycle,” she says. “What else can we consider?”
One alternative could be the churning of a planet’s outer layers in a way that doesn’t require giant shifting slabs. The deepest part of a terrestrial planet’s outermost shell becomes denser as pressures increase with depth. Rising molten rock from the planet’s hot interior can also add density and heat to the bottom of the shell, making the rock runnier and denser. Even just a 1 percent density change could produce globs of material dense enough to sink deeper into the planet, carrying carbon along for the ride, Elkins-Tanton proposes.
As the material sinks, it releases some water like a squeezed sponge. This carbon-containing water then seeps back toward the surface. Water loosens the bonds that hold rocks together, which lowers a rock’s melting point. If enough water accumulates, molten magma pools form and fuel volcanic eruptions. Together, these mechanisms could substitute for plate tectonics in the carbon cycle, Elkins-Tanton says. True, the process would be much slower than plate tectonics, but it could keep some planets’ climates livable, her simulations show.
Hot air Of course, the carbon cycle matters only if CO2 is the main driver of the atmospheric blanket that keeps a planet cozy enough for life-sustaining liquid water. Plenty of other greenhouse gases, such as ozone or nitrous oxide, could keep exoplanets temperate. One, however, would be particularly potent: hydrogen.
Earth used to have a lot more hydrogen in its atmosphere. In 2013, Wordsworth and planetary scientist Raymond Pierrehumbert, now at the University of Oxford, proposed that hydrogen could have kept Earth warm back when the sun was cool. They were attempting to resolve the faint young sun paradox (SN: 5/4/13, p. 30).
Early in Earth’s history, about 3.8 billion years ago, the sun shined 20 to 30 percent less brightly than it does now. Keeping the young planet warm posed a problem. Wordsworth and Pierrehumbert proposed that hydrogen, when combined with abundant nitrogen in the atmosphere, could serve as a paradox-resolving greenhouse gas. When hydrogen and nitrogen molecules collide in the air, the hydrogen molecules start wobbling differently. This wobbling increases the range of light wavelengths that hydrogen molecules absorb, amplifying the greenhouse effect. Hydrogen escaped from Earth’s atmosphere over time. But on larger rocky planets with stronger gravitational pulls, that hydrogen would stick around, Wordsworth says. With enough hydrogen and nitrogen, a planet can keep warm far outside of the CO2-based Goldilocks zone, Wordsworth says. Planets as far away from their sun as Pluto is to ours could stay above freezing. Even rogue planets alone in the cosmos with no parent star might keep warm enough to support life (SN: 4/4/15, p. 22).
The problem, however, is that these planets would need something akin to a carbon cycle to fine-tune hydrogen concentrations and prevent temperatures from getting too hot or too cold. Worse yet, at least on Earth, enterprising microbes feast on any available hydrogen for energy. Emerging life-forms could gorge on an exoplanet’s hydrogen, essentially eating the very thing keeping the planet warm enough for life. Those planets therefore might not stay habitable long enough for advanced life to evolve, Wordsworth says. The inhabitance paradox The hungry microbes might actually be good for hydrogen-wrapped planets, planetary scientist Dorian Abbot of the University of Chicago proposed at the AGU meeting in December. Higher temperatures make enzymes work faster and microbes more active. If temperatures rose, the hydrogen-chomping microbes would draw more hydrogen from the atmosphere and cool the planet. And if temperatures fell too far, microbe activity would fall and hydrogen levels would stabilize.
The ability of life, like those microbes, to fundamentally alter the climate and chemistry of its home planet poses a new paradox, Goldblatt said at the same meeting. Whether or not a planet is habitable could sometimes depend on whether life has already made itself at home there. He calls it the inhabitance paradox; the idea is an extension of the Gaia hypothesis, the proposal that organisms alter their surroundings to maintain a habitable environment. In other words, life could be a requirement for life.
The paradox showcases just how complex the hunt for habitable planets has become, Goldblatt says. “There are many other ways to support life — we just don’t know what they are yet,” he says. “Our imagination is limited to our experience. We’re going to observe other planets and see things we never have imagined.”
Most people think that autism is a disorder of the brain. But the skin may play a role, too, a new study suggests.
Nerve cells in the skin are abnormal in mice with mutations in autism-related genes, leading to poor touch perception, scientists report June 9 in Cell. This trouble sensing touch may influence the developing brain in a way that leads to social deficits and anxiety later in life.
The results raise the provocative idea that fixing abnormal senses may alleviate some of the behavioral symptoms of autism, says study coauthor David Ginty, a neuroscientist at Harvard Medical School. To explore the role of touch, Ginty and colleagues used mice that carried mutations in genes linked to autism. The genes are active in many places, including the brain. But the researchers used genetic tricks to place the mutated genes only in the peripheral nervous system — the collections of nerves outside the brain and spinal cord.
Adding mutations in a handful of autism-related genes only in peripheral nerves interfered with the mice’s sense of touch. These mice had trouble telling a smooth object from a rough one, and they had outsized reactions to harmless puffs of air. “They’re really touchy when you pick them up,” Ginty says. The sensory breakdown was caused by touch-sensing nerve cells that seemed to have trouble sending messages to the spinal cord, the researchers found.
Some mice also had behavioral deficits. Those with mutations in one of two genes — Mecp2 or Gabrb3 — in the peripheral nervous system, but not the brain, showed more signs of anxiety and interacted with other mice less than mice that didn’t have those mutations. Discovering that changes in the touch-sensing nerve cells could affect behavior was unexpected, Ginty says.
The skin’s influence seems to be important early in life. Social behaviors and anxiety didn’t suffer when the genes were first mutated in touch-sensing nerve cells during adulthood. The effect on behavior showed up only when the genes were abnormal during development, the team found.
That finding is “the most impressive part of the work,” says neuroscientist Kevin Pelphrey of George Washington University in Washington, D.C. The results emphasize how autism is an inherently developmental disorder, he says. Pelphrey and colleagues previously found that the brains of children with autism react differently to light touch, which fits with the idea that problems of touch may be involved in the disorder.
Next, Ginty and colleagues plan to figure out exactly when these genes do their important work in the peripheral nervous system. “We are now really interested in the window of time,” he says. “Presumably that window closes at some point, and we’re trying to figure out when that is.” The researchers will also explore ways to restore normal touch sensation, including drugs or genetic manipulations, that would work before the window closes.
It’s possible that other nerve cells outside the brain are affected in autism, too, says neuroscientist Aaron McGee of the University of Southern California in Los Angeles. “If you have these problems with peripheral nerves that have roles in active sensation, do you also have problems with the nerves that innervate the gut?” If so, that could help explain why people with autism often experience gut trouble.
McGee cautions that it’s difficult to compare behaviors of mice with symptoms of autism in people. But he says that the genetic experiments described in the paper are “awesome, thorough and significant.”
Pig fat has made the leap from kitchen staple to laboratory marvel for its ability to grow bone. Stem cells from the fat tissue of Yucatán minipigs grew into pieces of bone that were then successfully implanted into the pigs’ jaws, researchers report June 15 in Science Translational Medicine.
The team of bioengineers used cow bone scaffolds infused with stem cells from a minipig’s fat tissue to grow bone grafts in a special chamber in the lab. The new bones, which were personally fitted to each minipig’s jaw, fared better after six months than standard bone grafts not seeded with fat cells.
The new research brings scientists a step closer to one day using fat stem cells to repair humans’ broken or worn-out body parts.
Busy nerve cells in the brain are hungry and beckon oxygen-rich blood to replenish themselves. But active nerve cells in newborn mouse brains can’t yet make this request, and their silence leaves them hungry, scientists report June 22 in the Journal of Neuroscience.
Instead of being a dismal starvation diet, this lean time may actually spur the brain to develop properly. The new results, though, muddy the interpretation of the brain imaging technique called functional MRI when it is used on infants. Most people assume that all busy nerve cells, or neurons, signal nearby blood vessels to replenish themselves. But there were hints from fMRI studies of young children that their brains don’t always follow this rule. “The newborn brain is doing something weird,” says study coauthor Elizabeth Hillman of Columbia University.
That weirdness, she suspected, might be explained by an immature communication system in young brains. To find out, she and her colleagues looked for neuron-blood connections in mice as they grew. “What we’re trying to do is create a road map for what we think you actually should see,” Hillman says.
When 7-day-old mice were touched on their hind paws, a small group of neurons in the brain responded instantly, firing off messages in a flurry of activity. Despite this action, no fresh blood arrived, the team found. By 13 days, the nerve cell reaction got bigger, spreading across a wider stretch of the brain. Still the blood didn’t come. But by the time the mice reached adulthood, neural activity prompted an influx of blood. The results show that young mouse brains lack the ability to send blood to busy neurons, a skill that influences how the brain operates (SN: 11/14/15, p. 22).
That finding was enabled by technology that allowed the researchers to see neural activity and blood flow at the exact same time. It’s “a powerful application of cutting-edge imaging techniques,” says neuroscientist Alan Jasanoff of MIT.
Showing that oxygen demands are unheeded during early development is interesting, says neuroscientist Matthew Colonnese of George Washington University School of Medicine and Health Sciences in Washington, D.C. More studies are needed to say whether human infant brains behave similarly and, if so, how this process might sculpt the brain.
The results don’t mean that fMRI data from young children aren’t valuable, Hillman says. “What we are begging people to do is to make room for this hypothesis, and actually treat it as an opportunity.” Blood flow data might not be a good proxy for neural activity in newborns, but “it may well be measuring a change that is very important to normal brain development,” she says.
Here’s one good reason why people often take medications and use health products that don’t live up to expectations or just don’t work — digital word of mouth.
The reviews can be glowing. Take this scuttlebutt about a cholesterol treatment: “I have been using this product for 2 years. Within the first 3 – 4 months my cholesterol was down 30 points. Just got cholesterol tested last week: down from 245 to 196.”
That’s incredible. It might even be true. But the big picture is alarming: Patients’ online reviews of three over-the-counter drugs — two for lowering cholesterol and one for losing weight — greatly exaggerate how well these substances actually work for most people, says psychologist Mícheál de Barra of the University of Aberdeen in Scotland. Online reviewers portray these medications as working three to six times better than they do in clinical trials that randomly assign drugs or placebos to broad samples of volunteers, he says.
“To learn what works in medicine, you need systematically collected data, usually randomized clinical trials,” de Barra says. “It’s very risky to rely on observations and word of mouth, whether it’s electronic or in person.”
Online reviewers probably aren’t lying, at least not in most cases. Neither are online review readers unrealistically optimistic about health treatments. The problem is that people who benefit most from a medication are especially apt to post their experiences online. Review readers get bamboozled by a wave of positive recommendations that don’t accurately represent how a drug works, or doesn’t work, for people in general.
The duping doesn’t end there. Direct word of mouth about medical treatments, as well as glowing testimonials about health products in advertisements, also traffic in positively skewed information.
In some cases, science does, too. Researchers have recently raised alarms about the “file-drawer problem,” in which studies that find no statistical effects are not published (SN: 5/19/12, p. 26). Published studies reporting positive effects then look unjustifiably bulletproof.
Clinical trials can tilt results in other ways as well. Authors of published trials often fail to preregister details of what they plan to study and how they’ll measure it, enabling data manipulation, selective reporting of results and self-serving interpretations of findings. Clinical trials report patients’ “average” responses to, say, an anticholesterol drug, but do a poor job of predicting which individuals will benefit from that treatment. “Published evidence from randomized trials is already an amalgam of evidence-based medicine and hearsay,” notes Stanford University epidemiologist John Ioannidis. Online reviews are just old-fashioned word of mouth with a global bullhorn. But they offer one way to quantify the positive bias inherent in so much communication about medical treatments. Patients’ medication reviews that include numerical information, such as cholesterol levels before and after taking an anticholesterol drug, represent what Ioannidis calls “evidence-based hearsay.” Even if patients’ reviews rate treatments with a star system rather than including quantified measures of some kind, those opinions become powerful hearsay evidence for other patients, Ioannidis suspects.
De Barra evaluated 908 online reviews of two cholesterol reduction products, Benecol caramel smart chews and CholestOff, written on or before March 18, 2015. He also assessed 767 reviews of a weight-loss drug, Alli (orlistat), written on or before February 28, 2015.
Benecol reviewers reported a not-too-shabby average cholesterol decline of 45 milligrams per deciliter, versus a small average decline of 14 milligrams per deciliter in nine clinical trials. Respective numbers for CholestOff were 31 milligrams per deciliter and 13 milligrams per deciliter. Alli reviewers reported an average weight loss of about 10 kilograms after taking the drug for three months, versus an average of about two or three kilograms in two clinical trials. That disparity widened slightly after taking Alli for seven months.
Each drug garnered mainly positive reviews, some reporting effects far larger than the average, peppered with a few pans, De Barra reports in the March Social Science & Medicine.
What’s particularly concerning is that these three medications displayed small or negligible effects in clinical trials that probably already inflated how well the drugs work, Ioannidis says. So people searching for help in lowering cholesterol or shedding pounds may instead be getting a massive dose of disappointment from online reviews.
Online reviews can also exaggerate a treatment’s worst effects, whether real or alleged. Evidence-based hearsay may be particularly catchy online and in person when it’s frightening, de Barra suspects.
The anti-vaccination movement provides a potent example, due in part to the success of vaccines. When people face no immediate threat from measles or other infectious diseases, anti-vaccine stories may go viral, so to speak, thanks to misapplied but deeply felt intuitions. Two cognitive scientists, Helena Miton of Central European University in Budapest and Hugo Mercier of the Cognitive Sciences Institute in Bron, France, proposed this scenario in the November 2015 Trends in Cognitive Sciences.
However medical treatments acquire halos or horns, only well-conducted, transparent clinical trials can identify effective medical treatments, such as childhood vaccinations, and their potential side effects, Ioannidis says. But an ominous research trend is gathering steam, he warns. Researchers, professional societies, funders and lobbyists increasingly push to replace clinical trials of randomly selected volunteers with studies of interventions for select samples of people who eat certain foods, take certain drugs or behave in certain ways. The latter investigations may inflate a treatment’s effects even more than online patient reviews do, Ioannidis asserts.
Perhaps a new wave of studies showing how evidence-based hearsay misrepresents many medications will be just what the doctor ordered to resuscitate evidence-based medicine, he muses.
When you lock eyes with a baby, it’s hard to look away. For one thing, babies are fun to look at. They’re so tiny and cute and interesting. For another, babies love to stare back. I remember my babies staring at me so hard, with their eyebrows raised and unblinking eyes wide open. They would have killed in a staring contest.
This mutual adoration of staring may be for a good reason. When a baby and an adult make eye contact, their brain waves fall in sync, too, a new study finds. And those shared patterns of brain activity may actually pave the way for better communication between baby and adult: Babies make more sweet, little sounds when their eyes are locked onto an adult who is looking back. The scientists report the results online November 28 in the Proceedings of the National Academy of Sciences.
Psychologist Victoria Leong of the University of Cambridge and Nanyang Technological University in Singapore and colleagues invited infants into the lab for two experiments. In the first, the team outfitted 17 8-month-old babies with EEG caps, headwear covered with electrodes that measure the collective behavior of nerve cells across the brain. The infants watched a video in which an experimenter, also outfitted in an EEG cap, sung a nursery rhyme while looking either straight ahead at the baby, at the baby but with her head turned at a 20-degree angle, or away from the baby and with her head turned at a 20-degree angle. When the researcher looked at the baby (either facing the baby or with her head slightly turned), the babies’ brains responded, showing activity patterns that started to closely resemble those of the researcher.
The second experiment moved the test into real life. The same researcher from the video sat near 19 different babies. Again, both the babies and the researcher wore EEG caps to record their brain activity. The real-life eye contact prompted brain patterns similar to those seen in the video experiment: When eyes met, brain activity fell in sync; when eyes wandered, brain activity didn’t match as closely.
The baby’s and the adult’s brain activity appeared to get in sync by meeting in the middle. When gazes were shared, a baby’s brain waves became more like the researcher’s, and the researcher’s more like the baby’s. That finding is “giving new insights into infants’ amazing abilities to connect to, and tune in with, their adult caregivers,” Leong says.
What are simpatico brain waves actually good for, you might ask? Well, researchers don’t know exactly, but they have some ideas. When high school students’ brain waves were in sync with one another, the kids reported being more engaged in the classroom, a recent study found. And when two adults reach a mutual understanding, their brains synchronize, too, says another study. These findings hint that such synchronization lets signals flow easily between two brains, though Leong says that much more research needs to be done before scientists understand synchronization’s relevance to babies’ communication and learning. That easy signal sending is something that happened between the babies and the adult, too. When the experimenter was looking at the babies, the babies made more vocalizations. And in turn, these sweet sounds seemed to have made the experimenter’s brain waves even more similar to those of the babies.
It’s a beautiful cycle, it seems, when eyes and brains meet. And that meeting spot is probably where some interesting learning happens, for both adult and baby.
NEW ORLEANS — Jupiter’s Great Red Spot has deep roots. Data from the first pass of NASA’s Juno spacecraft over the incessant storm show that its clouds stretch at least 350 kilometers down into the planet’s atmosphere. That means the storm is about as deep as the International Space Station is high above the Earth.
Juno has been orbiting Jupiter since July 4, 2016, and it made its first close flyby of the red spot about a year later (SN Online: 7/7/17). As the spacecraft swooped 9,000 kilometers above the giant storm, Juno’s microwave radiometer peered through the deep layers of cloud, measuring the atmosphere’s temperature down hundreds of kilometers. “Juno is probing beneath these clouds, and finding the roots of the red spot,” Juno co-investigator Andrew Ingersoll of Caltech said December 11 at a news conference at the American Geophysical Union’s fall meeting. Cheng Li of Caltech presented the research at AGU on December 12. The radiometer probes different layers of the atmosphere by measuring the gas in six different microwave wavelengths. Ingersoll and his colleagues found that the gas beneath the red spot’s surface gets warmer with depth, and a warm zone at the same location as the spot was visible down to 350 kilometers The fact that the 16,000-kilometer-wide spot is warmer at the bottom than at the top could help explain the storm’s screaming wind speeds of about 120 meters per second. Warm air rises, so the internal heat could provide energy to churn the storm.
Juno principal investigator Scott Bolton of the Southwest Research Institute in San Antonio notes that the spot “goes as deep as we can see,” but it could go deeper. “I’m not sure we’ve established the true foot,” he says. On a future flyby, Juno will try to use gravity data to detect the storm at depths of thousands of kilometers. If the spot does go down that deep, theorists will struggle to explain why, Bolton says.
The only previous data on Jupiter’s interior came from the Galileo spacecraft, which ended its mission by entering Jupiter’s atmosphere at a single point in 1995. “I like to say that if aliens sent a probe to Earth and it landed in the Sahara, they would conclude the Earth is all desert,” says planetary scientist Michael Wong of Caltech, who was not involved in the new study. “Juno getting this global view gives us a new understanding of the inner workings … We have never really seen the interior of a giant planet in this way before.”
NEW ORLEANS — For the first time, scientists have definitively linked human-caused climate change to extreme weather events.
A handful of extreme events that occurred in 2016 — including a deadly heat wave that swept across Asia — simply could not have happened due to natural climate variability alone, three new studies find. The studies were part of a special issue of the Bulletin of the American Meteorological Society, also known as BAMS, released December 13. These findings are a game changer — or should at least be a conversation changer, Jeff Rosenfeld, editor in chief of BAMS, said at a news conference that coincided with the studies’ release at the American Geophysical Union’s annual meeting. “We can no longer be shy about talking about the connection between human causes of climate change and weather,” he said.
For the last six years, BAMS has published a December issue containing research on extreme weather events from the previous year that seeks to disentangle the role of anthropogenic climate change from natural variability. The goal from the start has been to find ways to improve the science of such attribution, said Stephanie Herring of the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information in Boulder, Colo., who was lead editor of the latest issue.
To date, BAMS has published 137 attribution studies. But this is the first time that any study has found that a weather event was so extreme that it was outside the bounds of natural variability — let alone three such events, Herring said.
Story continues below map In addition to the Asia heat wave, those events were the record global heat in 2016 and the growth and persistence of a large swath of high ocean temperatures, nicknamed “the Blob,” in the Bering Sea off the coast of Alaska. The unusually warm waters, which lingered for about a year and a half, have been linked to mass die-offs of birds, collapsed codfish populations in the Gulf of Alaska and altered weather patterns that brought drought to California.
Many of the other 24 studies in the new issue found a strong likelihood of human influence on extreme weather events, but stopped short of saying they were completely out of the realm of natural variability. One study found that an already strong El Niño in 2016 was probably enhanced by human influence, contributing to drought and famine conditions in southern Africa. Another reported that greenhouse gas–driven warming of sea surface temperatures in the Coral Sea was the main factor driving an increase in coral bleaching risk along the Great Barrier Reef. But not all of the studies linked 2016’s extreme events to human activity. Record-breaking rainfall in southeastern Australia between July and September, for example, was due to natural variability, one study found.
With hurricanes, wildfires and drought, 2017 is chock-full of extreme event candidates for next year’s crop of BAMS attribution studies. Already, the likelihood of human influence on the extreme rainfall from Hurricane Harvey is the subject of three independent studies, two of which were also presented at the American Geophysical Union meeting. The storm dropped about 1.3 meters of water on Houston and its surrounding areas in August. The three studies, discussed in a separate news conference December 13, found that human influence probably increased the hurricane’s total rainfall, by anywhere from at least 15 percent to at least 19 percent.
Story continues below image “I think [the BAMS studies] speak to the profound nature of the impacts we’re now seeing,” says Michael Mann, a climate scientist at Penn State who was not involved in any of the studies. But Mann says he’s concerned that many researchers are too focused on quantifying how much human influence was responsible for a particular event, rather than how human influence affects various processes on the planet. One example, he notes, is the established link between rising temperatures and increased moisture in the atmosphere that is also implicated in Hurricane Harvey’s extreme rainfall.
Another possible issue with attribution science, he says, is that the current generation of simulations simply may not be capable of capturing some of the subtle changes in the climate and oceans — a particular danger when it comes to studies that find no link to human activities. It’s a point that climate scientist Andrew King of the University of Melbourne in Australia, who authored the paper on Australia’s rainfall, also noted at the news conference.
“When we find no clear signal for climate change, there might not have been a human influence on the event, or [it might be that] the particular factors of the event that were investigated were not influenced by climate change,” he said. “It’s also possible that the given tools we have today can’t find this climate change signal.”
Rosenfeld noted that people tend to talk about the long odds of an extreme weather event happening. But with studies now saying that climate change was a necessary condition for some extreme events, discussions about long odds no longer apply, he said. “These are new weather extremes made possible by a new climate.”
The neutron star collision heard and seen around the world has failed to fade. That lingering glow could mean that a jet of bright matter created in the crash has diffused into a glowing, billowy cocoon that surrounds the merged star, researchers report online December 20 in Nature.
Gravitational waves from the collision between two ultradense stellar corpses was picked up in August by the Advanced Laser Interferometer Gravitational-Wave Observatory, LIGO, and its sister experiment in Italy, Advanced Virgo (SN: 11/11/17, p. 6). Using telescopes on the ground and in space, physicists raced to conduct follow-up observations, and found that the collision released light across the electromagnetic spectrum. Right away, the event looked unusual, says astrophysicist Kunal Mooley, who conducted the research while at the University of Oxford. Physicists think that a jet of fast-moving, bright material blasts out of the center of neutron star collisions. If that jet is aimed directly at Earth, telescopes can see it as an ephemeral flash of light called a short gamma-ray burst, or GRB. But the gamma-ray signals produced by the August collision were 10,000 times less bright than those seen in other detected short gamma-ray bursts. Even stranger, X-rays and radio waves from the event didn’t appear until about 16 days after the collision. Most short gamma-ray bursts are visible in X-rays and radio waves right away and fade over time. Astronomers thought those oddities meant the jet was facing slightly away from Earth and expected the light to fade quickly. But Mooley and colleagues continued tracking the glow with three radio telescope arrays on three continents for more than 100 days after the collision. Radio wave emissions continued to brighten for at least 93 days, and are still visible now, the team found. (X-rays were temporarily blocked when the neutron star moved behind the sun from Earth’s perspective.)
“This thing continues to rise, instead of fading into oblivion as we expected,” says astrophysicist Wen-fai Fong of Northwestern University in Evanston, Ill., who was not involved in the new study.
The finding may mean that astronomers are seeing a new kind of gamma-ray burst. Mooley and colleagues suggest that the rise in radio wave emissions could be explained if the jet slammed into a shell of neutron-rich material kicked out in the neutron star crash, transferring most of its energy to that debris and smothering the jet. That extra energy could create a glowing cocoon that keeps radiating far longer than the original blast.
The new result is “really challenging our understanding of what physics is happening from this merger,” Fong says. But, she adds, “the jury is still out on whether this is the same as the short GRBs we’ve seen over the past decade, or whether it’s something completely different,” such as a luminescent cocoon. She and her colleagues also took radio wave observations of the merged stars in the first 100 days after the collision. The team is preparing a paper with a different interpretation that includes a jet emerging from the wreckage later, she says.
Other explanations for the lingering light are possible, Mooley acknowledges. Future detections “will give us an opportunity to really study … what fraction of neutron star mergers give rise to [short] GRBs and what fraction give rise to other phenomena and explosions that we haven’t seen so far in our universe,” he says.
