Innholdsfortegnelse for January/February 2020 i Discover

Israel Shoots for the Moon The lunar lander Beresheet made history this year, though not exactly how its creators intended. Israeli nonprofit SpaceIL, teaming up with state-owned defense company Israel Aerospace Industries, built and operated the craft. SpaceIL was founded for one main purpose: getting to the moon. It was a response to Google’s Lunar XPRIZE, which in 2007 promised $20 million to a company that could land gently on the moon and complete a small series of tasks. No team had claimed the prize by the time it expired, after repeated extensions, in 2018. The Beresheet mission continued anyway, launching Feb. 22 on a Falcon 9 rocket made by U.S. company SpaceX. It entered lunar orbit on April 4, making it the first privately funded spacecraft — and Israel…

Scientists adding human brain genes to monkeys — it’s the kind of thing you’d see in a movie like Rise of the Planet of the Apes. But Chinese researchers have done just that, improving the short-term memories of the monkeys in a study published in March in the Chinese journal National Science Review. While some experts downplayed the effects as minor, concerns linger over where the research may lead. The goal of the work, led by geneticist Bing Su of Kunming Institute of Zoology, was to investigate how a gene linked to brain size, MCPH1, might contribute to the evolution of the organ in humans. All primates have some variation of this gene. However, compared with other primates, our brains are larger, more advanced and slower to develop; the researchers…

Since the end of the space shuttle program in 2011, the U.S. has used Russian Soyuz spacecraft every time it wants to, well, shuttle humans to and from space. While NASA is busy working on its own solution, the agency has increasingly turned to private companies, such as Elon Musk’s SpaceX, to cover its off-planet transportation needs. Although SpaceX has successfully flown cargo flights for NASA since 2012 via the reusable Dragon spacecraft, the company has yet to launch humans in its so-called Crew Dragon capsule. Originally promised to launch in 2017, the program has seen multiple delays. It is, after all, rocket science, and the path has not been easy. But this year seemed different. NASA’s pre-purchased Soyuz flights run out by the end of 2019, and SpaceX —…

In February, a very real paper ran in Scientific Reports titled, “Human Mind Control of Rat Cyborg’s Continuous Locomotion with Wireless Brain-to-Brain Interface.” It described how existing technology — such as brain-brain interfaces (BBIs) and, incredibly, rat cyborgs — can work together to produce that eye-popping title. BBIs and brain-machine interfaces (BMIs) have already helped improve how people control prosthetics and other devices. But the technology can also function the other way around — instead of a brain controlling a device, a machine can alter brain patterns or “import tactile information back to the brain,” as the study’s authors put it. So, in effect, BMIs could allow for mechanically “controlling” others’ brains. Here’s how it works in practice: A human manipulator has movement-related thoughts, which a wearable EEG — a…

Nearly 37 million people have human immunodeficiency virus (HIV), the cause of AIDS. The go-to treatment for the infection, antiretroviral therapy (ART), can prevent the disease’s progression, allowing people to live longer and healthier lives. But even with ART, the virus still lingers in the body by copying itself into the DNA of infected cells. This year, researchers described a new form of ART which, in combination with CRISPR gene editing, eradicated the virus during testing on mice — a big step toward new therapeutic avenues for HIV patients. To mimic a human infection in mice, the researchers used “humanized mice,” which make human immune cells, rather than mouse immune cells. These human cells are susceptible to HIV. When the team injected the mice with the virus, they saw the…

Usually, getting to another planet is supposed to be the hardest part of the mission. Not so for NASA’s InSight lander. The probe touched down on the Red Planet in November 2018, and immediately started taking weather measurements and photographing its new permanent home. Unlike its more famous sibling missions like Opportunity and Curiosity, InSight is no rover, and will instead perform its whole mission from one location in the broad plain of Elysium Planitia near Mars’ equator. But in 2019, that mission had a major hiccup. A part of InSight’s Heat Flow and Physical Properties Package (HP3) — an instrument meant to burrow about 16 feet underground to measure how heat travels through martian soil — got stuck on Feb. 28, shortly after it began drilling. It had burrowed…

In February, an international traveler carrying the measles virus passed through Boston’s busy South Station bus terminal. Once discovered, the Boston Public Health Commission urged anyone in the person’s path who was unvaccinated — other travelers, local residents, bus drivers, station employees — to see their doctors. “Measles is the most contagious virus we know about,” says H. Cody Meissner, chief of pediatric infectious diseases at Floating Hospital for Children at Tufts Medical Center in Boston. “Hundreds of people could have been exposed.” A cough or sneeze from an infected individual can spray particles of the virus — each one only about 5 microns, barely smaller than a human red blood cell — that can remain infectious and airborne for up to two hours. Measles easily infects around 9 in…

Smaller than a sparrow, a 99-million-year-old bird preserved in amber made some very big news in July. “I’ve never seen anything like this, or even close,” says paleontologist Jingmai O’Connor of Beijing’s Institute of Vertebrate Paleontology and Paleoanthropology. O’Connor is a co-first author on the Current Biology paper that introduced the world to Elektorornis chenguangi, a new species of Cretaceous bird known from a single partial specimen. Frozen in time in a piece of Burmese amber, the single hindlimb of Elektorornis has traits not seen in any other bird, living or extinct. The animal’s third toe is extremely elongated — longer than the entire lower leg bone. And on this bizarre supertoe are strange filaments so unique they’re hard to describe, even for researchers studying them: “Imagine a scale on…

A really old rhino tooth has opened a new path toward understanding the tree of life — including, potentially, our own branch. In September, researchers detailed in Nature how, using the tooth of a 1.77-million-year-old rhino from the Republic of Georgia, they were able to revise its family tree. The team’s success has implications far beyond rhino ancestry: It’s proof of concept that it’s possible to map out evolutionary relationships between species, with confidence and on a molecular level, without DNA. Instead, the team extracted and sequenced proteins preserved in the rhino’s tooth enamel. “Protein sequences are the best proxy [for DNA],” says University of Copenhagen’s Enrico Cappellini, lead author of the study. Cappellini is a specialist in paleoproteomics, the study of ancient proteins preserved in fossils. “In a way,…

Astronomers found an entirely unexpected feature on Titan, Saturn’s largest moon, this year: a ribbon of exposed bedrock ice that wraps nearly halfway around the satellite. This unique feature came into view thanks to a recently developed analysis technique never before used on Titan. Researchers had previously spotted surprisingly diverse landscapes on the moon, from broad plains to sandy dunes and even rivers and lakes. Since the world is so cold, these features are made up of liquid methane and other organic compounds that slosh over a bedrock of solid, rock-hard ice. But it’s tough to get good observations of the surface, because the moon’s atmosphere is so dense and hazy. So instead of examining individual pixels from images and scouring them for details and data, the researchers used a…

A healthy heart needs healthy vessels to pump oxygen to the rest of the body. Cardiovascular diseases can damage these vessels, and current treatments — like grafting vessels from elsewhere in a person’s body or from synthetic sources — come with serious risks. But in March, a team of researchers announced in Science Translational Medicine that they had made vessels in the lab that, once transplanted into people, can turn into functionally living tissue. Researchers at Duke University, Yale University and biotech company Humacyte collected cells from cadavers — specifically, cells from muscles that make up blood vessels and that form vessels’ inner lining. They seeded these cells onto a biodegradable mesh scaffold, where the cells created proteins to surround the structure. Then, once the structure was built, the scientists…

This spring, astronomers revealed the first image ever taken of a black hole, bringing a decades-long effort to a dramatic conclusion. The image offers humanity its first glimpse of the gas and debris that swirl around the object’s event horizon, the point beyond which material disappears forever. A staple of science fiction has finally become visibly real. “We are delighted to be able to report to you today that we have seen what we thought was unseeable,” said Event Horizon Telescope (EHT) founding director Shep Doeleman when he announced the finding in April. The team of scientists made their announcement simultaneously in seven different countries, accompanied by a series of scientific papers published at the same time in The Astrophysical Journal Letters. The subject of the photo session was a…

One million species face extinction, more than ever before in human history, according to a U.N. report released in May. And humanity is responsible. The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) based the assessment on some 15,000 sources that consider the causes and consequences of environmental changes over the past 50 years. The findings are stark. The authors found that about 25 percent of the world’s plants and animals are vulnerable to extinction. These include over a third of marine mammals and more than 40 percent of amphibians. Even domesticated animals are at risk: Over 9 percent of domesticated mammal breeds used for food and agriculture already may have been lost. This rapid decline of the natural world endangers global food security and quality of life. For…

From Antarctica to Greenland to the Himalayas, study after study in 2019 reported the world’s ice is melting at an accelerated rate. New scientific innovations allowed researchers to better quantify mass ice losses, and their studies exposed startling trends. The new findings paint a troubling future for glaciers around the world: If current ice-loss rates continue, scientists predict the collapse of glaciers around the world before the end of the century. Wet Paws Sled dogs wade through a melting ice sheet in Greenland as researchers from the Danish Meteorological Institute travel to retrieve equipment in June. Three months earlier, a team of scientists in Denmark, the U.K. and the U.S. had published a study in Science Advances, predicting that over 25 percent of global sea level rise is due to…

In his 2013 book, Schrödinger’s Killer App, Louisiana State University theoretical physicist Jonathan Dowling predicted what he called “super exponential growth.” He was right. Back in May, during Google’s Quantum Spring Symposium, computer engineer Hartmut Neven reported the company’s quantum computing chip had been gaining power at breakneck speed. The subtext: We are venturing into an age of quantum supremacy — the point at which quantum computers outperform the best classical supercomputers in solving a well-defined problem. Engineers test the accuracy of quantum computing chips by using them to solve a problem, and then verifying the work with a classical machine. But in early 2019, that process became problematic, reported Neven, who runs Google’s Quantum Artificial Intelligence Lab. Google’s quantum chip was improving so quickly that his group had to…

Nine thousand years ago — a couple of millennia after the first humble farming villages appeared in the Middle East — Motza was a town ahead of its time, a vanguard of urban life. Home to thousands, the roughly 80-acre site was about 10 to 100 times larger than other settlements of the day. “Mega-huge,” says Hamoudi Khalaily, who co-led excavations at the site, which nestles between olive and dun-colored hills in present-day Israel. In July, after 16 months of digging, the Israel Antiquities Authority (IAA) team unveiled Motza’s grandeur. The town was a dense hub of workshops, public halls and private homes linked by roads and alleys. Evidence of art and trade was everywhere, including bountiful artifacts such as handcrafted jewelry, Red Sea shells and Anatolian volcanic glass. “You…

Where are America’s volcanoes? Hawaii, Alaska, the Pacific Northwest and Yellowstone National Park might spring to mind, but there are more than 150 potentially active volcanoes across the U.S. and its territories, including in Arizona, Utah and Colorado — and many have erupted in the geologically recent past. In 2018, the U.S. Geological Survey (USGS) identified 57 volcanoes it considers “Very High” or “High” threats based on factors such as the likelihood of future eruptions and their proximity to population hubs. For example, Washington state’s Mount Rainier is less than 60 miles from Seattle. Some of these higher-risk volcanoes pose very real dangers to large numbers of people. Others, such as those in the sparsely populated Aleutian Islands, which arc between Alaska and Russia, could pose a significant aircraft hazard.…

Quantum weirdness struck again in 2019. An experiment described in Nature in June settled a passionate debate that’s divided physicists for over a century, while also raising new questions. Researchers announced they’d tracked a quantum leap in unprecedented detail, showing that it’s possible not only to predict when a particle might jump, but also — bizarrely — reverse it mid-hop “There’s more to the story of quantum physics than we thought,” says physicist Zlatko Minev, a research scientist at IBM who led the experiment while at Yale University. The notion of a quantum jump originated in 1913, when Danish physicist Niels Bohr introduced the revolutionary idea that electrons only circle the nucleus of atoms in discrete orbits, or energy levels. Electrons jump from one level to another, Bohr hypothesized, by…

On July 1, Emory University mathematician Hao Huang quietly proved a theorem — and the mathematics and computer science worlds roared. In an elegant argument, laid out over six pages, Huang unequivocally proved the sensitivity conjecture, a thorn in the side of computer scientists for decades. The proof ignited the mathosphere. “Amazingly short and beautiful,” blogged Gil Kalai, a mathematician at the Hebrew University of Jerusalem. It “shows that people can still find simple proofs of deep, open questions,” says Cristopher Moore, a computer scientist and mathematician at the Santa Fe Institute. A long line of thinkers over nearly 30 years has tangled with the problem. But until Huang came along, it remained a mathematical itch that no one could scratch. The conjecture relates to mathematical structures called Boolean functions,…

Southern California is no stranger to earthquakes, but research published last summer shows it’s home to far more than previously thought. Seismologists at Caltech and Los Alamos National Laboratory identified 1.81 million tiny tremors hidden in data from 2008 to 2017 — roughly one every three minutes. This newly detected seismic activity has already helped scientists take steps toward fully understanding how earthquakes start. In the May study, published in Science, researchers unearthed these rumblings in a new catalog of local earthquakes. They used a technique called template matching, which requires supercomputers to comb through the shake-induced background noise of helicopters, construction and Los Angeles traffic. From that sea of squiggles, the machines can pluck out vibrations with the same shape as larger quakes. This comprehensive compilation helps resolve a…

Will 2020 be the year humans start walking around with computers in their heads? Elon Musk thinks so. Neuralink, Musk’s secretive biohacking company, launched in 2016 with the promise of implementing cutting-edge technology directly into people’s brains. At a press conference in July, the Neuralink team announced plans for a chip, dubbed the N1, that would physically attach to a user’s brain through a “neural lace” — a network of tiny threads. Each thread would send and receive electrical pulses in the brain. The company claims the tech could be helpful in the medical field, possibly giving paraplegic patients the ability to walk and people with vision loss the ability to see. But the team also wants to go beyond medical uses and potentially implant the N1 into the brain…

In 2019, Americans saw rain, rain and more rain: The 12-month period ending in June took the crown as the wettest ever recorded in the contiguous U.S. But that was the fourth time the record had been broken in 2019 — the previous 12-month precipitation record had been set in May, which had broken the record set in April, which had broken the record set in February. As climate change continues, scientists fear these record-breaking wet years could become more common. According to the National Oceanic and Atmospheric Administration, the sky over America poured almost 38 inches of water between July 2018 and June 2019 — almost 8 inches above average, according to the past 125 years of national precipitation data. Nearly the entire country experienced above-average precipitation during the…

We’re all here thanks to continents. Among rocky planets in the solar system, only ours has masses of less-dense rock that rise above surrounding crust. Yet our planet wasn’t born with them. We know that these land masses are a direct consequence of plate tectonics, when slabs of crust, continental and oceanic, interact as they move across the planet’s melted mantle. But we don’t know when or how quickly the continents formed — it’s one of the most challenging questions about Earth’s early history. Some geologists believe most of the continents popped up in the last billion years. Others think they have been forming slowly and steadily since the planet took shape some 4.6 billion years ago. Still other schools of thought suggest the land masses formed in fits and…

After years of ethical debates and breakthroughs in the lab, CRISPR has finally made its way to clinical trials. Researchers are now looking at whether the DNA-editing tool, as well as more conventional gene therapies, can effectively treat a wide array of heritable disorders and even cancers. “There’s been a convergence of the science getting better, the manufacturing getting much better, and money being available for these kinds of studies,” says Cynthia Dunbar, a senior investigator at the National Heart, Lung, and Blood Institute. “It’s truly come of age.” CRISPR-ING OUT DISEASE CRISPR — formally known as CRISPR-Cas9 — has been touted as an improvement over conventional gene therapy because of its potential precision. CRISPR (clustered regularly interspaced short palindromic repeats) is a genetic code that, contained in a strand…

Since 2008, when their fragmentary fossils first turned up in a Siberian cave, the Denisovans have been the most mysterious branch of the human family tree. The archaic humans, like Neanderthals, lived at the same time as early Homo sapiens but have been extinct for tens of thousands of years. For nearly a decade, we’ve known Denisovans from only one site, which yielded just a shard of finger bone and a few teeth from four individuals — and ancient DNA extracted from the scant remains. In 2019, however, a series of discoveries revealed our evolutionary kin in greater detail than ever, answering some questions but also presenting new mysteries. One thing is clear: The Denisovans were much more complex than we thought, occupying diverse and sometimes extreme environments spread over…

On New Year’s Day 2019, the far-flung New Horizons spacecraft, which visited Pluto in 2015, set a new record when it buzzed by the most distant object yet visited by humanity: a remote space rock nicknamed Ultima Thule. The object — officially dubbed 2014 MU69 — orbits the sun a whopping 4 billion miles from Earth, deep within the realm of frozen rocks called the Kuiper Belt. That distance meant it took more than six hours for the spacecraft’s signals — traveling at light-speed — to reach Earth. The delay will only increase as New Horizons continues speeding deeper into space at 9 miles per second. It won’t finish sending back data on the space rock until summer 2020. When the first images trickled in, they revealed Ultima Thule to…

Scott Maxwell, former Mars rover driver team lead “Put simply, I loved Opportunity, as I did her twin sister, Spirit. I was privileged to be part of a team that was ecstatically devoted to them for years. We sacrificed dinners with family, vacations, whole marriages to those rovers. And they were worth it: In exchange, they gave us a planet. They were our eyes and ears, our remote robot bodies. “The thought of saying goodbye to Opportunity fills me with mixed emotions: pride, certainly, at her enormous accomplishments, but grief and despair at her loss. And, truthfully, I think the pride will have to wait a while. There’s no room for it now.” Abby Fraeman, deputy project scientist, who first worked with the mission as a teenager “In terms of the science…

At the northern tip of the Philippine island of Luzon lies Callao Cave, an expansive, seven-chamber limestone warren. In April, researchers reported in the journal Nature that they’d uncovered the bones of a now-extinct, previously unknown human species near the far end of the first chamber. The discovery adds to growing evidence that human evolution and dispersal out of Africa is much more complicated than scientists once thought — and that we’re just starting to understand Southeast Asia’s role in that story. “There is no reason why archaeological research in the Philippines couldn’t discover several species of hominin,” Philip Piper, an archaeologist at the Australian National University who coauthored the new research, said in a statement. “It’s probably just a matter of time.” In 2007, Piper and an international team…

“It’s a big honkin’ animal.” That’s how College of Charleston paleontologist Scott Persons describes the fossil that happens to share his name. “Scotty,” named for a celebratory bottle of scotch cracked open to toast its discovery, is the biggest Tyrannosaurus rex in the fossil record — and the most elderly. The first bits of the animal surfaced back in 1991 in southwestern Saskatchewan, Canada, encased in iron-rich, extremely hard sandstone, which made excavation difficult and time-consuming. At the time, Persons notes, “no one knew how much of the animal was there, or how big it was.” It would take decades for researchers to excavate and prepare the bones for study. In fact, it wasn’t until March, when Persons and colleagues published the first full analysis of the animal in The…

So many older people experience the telltale symptoms of Alzheimer’s disease, like forgetfulness and muddled thinking. Yet postmortem autopsies often find none of the amyloid plaques or tau tangles that are hallmarks of the mind-robbing illness. Now, scientists may have solved this perplexing mystery: These patients are probably affected by a newly identified degenerative disorder that mimics Alzheimer’s and may be just as prevalent among older adults. Called LATE (limbic-predominant age-related TDP-43 encephalopathy), it mainly affects the “oldest old” — generally people older than 85. It also seems to be associated with deposits of an errant version of a protein called TDP-43, which collect in brain regions governing memory, like the hippocampus and middle frontal gyrus, as well as areas that regulate emotions and survival instincts, like the amygdala. Roughly…

Anorexia nervosa ravages bodies. The well-known eating disorder tricks people into thinking they’re overweight — to the point that they starve themselves, sometimes to death. “It’s a mammoth effort to be able to do that,” says Cynthia Bulik, a psychiatric researcher at the University of North Carolina. “Most bodies rebel against it.” Bulik co-led a genome-wide analysis that revealed genetic links between anorexia and other psychiatric disorders. Anorexia was long seen as an affliction of vanity that mostly affected white, upper-middle class teenage girls. But although more women than men are diagnosed with the condition, it can affect anyone. Worldwide, anorexia has the highest mortality rate of any psychiatric disease: Only 30 percent of sufferers fully recover. People with the disease can push themselves to a body mass index in…

The average human speaks at a rate of up to 150 words per minute, making spoken conversation one of the most effective ways to communicate. “We take for granted how effortless it is to convey so much information in such a short amount of time,” says Edward Chang, a neurosurgeon at the University of California, San Francisco. “That is, until you lose this ability from an injury.” Brain injuries such as stroke and neurological disorders like amyotrophic lateral sclerosis (ALS) can destroy vocal communication, socially isolating patients or requiring them to use prostheses. The best of these prostheses are essentially brain-controlled typewriters: A person moves a computer cursor with brain signals detected by a neural implant, painstakingly selecting one letter at a time. Eight words per minute is fast. (Perhaps…

The fungus among us is a key player in the ecosystem, breaking down organic matter to provide nutrients to other organisms. Now we know that fungi were getting down to business up to a billion years ago. Newly classified Ourasphaira giraldae from the Canadian Arctic is 900 million to 1 billion years old, pushing back the fossil record for these organisms by about 500 million years. The fungi fossils change our backstory, too. The oldest animals in the current fossil record only go back about 560 million years. (And if you’re wondering what the oldest fossil of any organism is, well, that’s hotly contested, but some researchers believe impressions on rock more than 4 billion years old represent the earliest recorded life on the planet.) “Fungi are, in the ‘tree…

What’s brown, slimy and washing up on beaches from Mexico to Africa? Sargassum — a smelly seaweed that’s been traversing the Atlantic Ocean in massive clumps over the last few years. On satellites, it looks like a single, monstrous mass, but it appears on beaches in stinky, sticky clusters. The great Atlantic Sargassum belt, as scientists have dubbed it, was identified in a paper published in July in the journal Science. Researchers first spotted it via European Space Agency satellites in 2011, when the brown algae was observed growing in massive quantities. Almost every year since, the seaweed has bloomed in the summer, deposited seeds in the winter and repeated the cycle when temperatures started to rise again. Though summer 2018 saw the largest stretch of seaweed on record —…

Between a rock and a hard place? That’s just where Lithoredo likes it. Researchers found the new-to-science shipworm, a kind of clam, in the Abatan River on the Philippines’ Bohol Island. It was a stunning sight. “It is unlike any other shipworm, both in its appearance and its unusual habits, and this was apparent from the very first moment I laid eyes on it,” says marine biologist Dan Distel, executive director of the Ocean Genome Legacy Center at Northeastern University. He’s also the senior author of the June paper describing the animal in the journal Proceedings of the Royal Society B. Shipworms got their name because they bore through wood that’s in contact with water, eating the material. They leave behind tunnels lined with the calcium carbonate that they secrete,…