You are here
Science is said to be moving faster than ever before. In fact, the pace is usually limited by the flow of information—I can’t respond to your results until I know about them, and journals are notoriously slow. The arXiv, which hosts manuscripts that may be submitted for peer review, is not. Put your preprint in today, watch it go public tomorrow... and see it get slapped down three weeks later.
Superconductivity is a hidden workhorse of today’s medical and scientific establishment. The way to get high magnetic fields is to use a very large current loop. In ordinary conductors, the imperfect conduction of electrons heats the metal, which increases the resistance of the metal. The whole feedback loop terminates when your finely designed metallic coil turns into a small glowing metallic puddle—often considered a bad thing.
In June 2013, Keith Musselman was living in the Canadian Rockies when the nearby Bow River flooded. “We were in a valley, so we were stuck for about five days,” Musselman told Ars. “The community was devastated.”
The flood was one of the costliest and most devastating natural disasters in Canada’s history, with five people killed, more than 100,000 evacuated, and extreme property damage. Heavy rainfall falling on late snow in the mountains had overwhelmed rivers and reservoirs, and Musselman, a hydrologist, realized that this kind of rain-on-snow flooding wasn’t properly understood.
“Forecasters have a good handle on what happens when rain falls,” he says. “But when that rain falls in mountains where there’s deep snow, we don’t have a good handle on what the flood volume will be.”
On Friday, a California jury hit Monsanto with $289 million in damages in a lawsuit brought by a patient suffering from terminal cancer, accepting the plaintiff's claims that his disease was caused by the company's popular herbicide, Roundup. The suit neatly sidestepped the complicated epidemiology of the active ingredient in the herbicide—glyphosate—and instead made the claim that the cancer was the result of glyphosate's interactions with other chemicals in Roundup—a claim for which there is even less evidence.
The suit is one of hundreds in progress and will almost certainly be appealed by Monsanto, which was recently purchased by chemical giant Bayer.
According to CNN, the suit was filed by a former groundskeeper for a school system near San Francisco named Dewayne Johnson. As part of his job, Johnson regularly used the popular herbicide and claimed that he suffered extensive exposure during two accidents within the past decade.
Since 1959, a unique breeding experiment has been underway in southwestern Siberia. Its founder, Dmitry Belyaev, was intrigued by the characteristics of domestication, and he observed that foxes varied in their responses to humans—some fearful, some aggressive, and a few displaying “a quiet exploratory reaction without fear or aggression.” What would happen, he wondered, if you bred just the most chilled-out foxes?
Within a few generations of doing just this, remarkable transformations were underway. The foxes were calmer and friendlier when approached—and also more baby-faced, with floppy ears, patchy coloring, and curlier tails. This group of tame foxes, along with a second group bred for their aggression, have been transformational in our understanding of domestication.
And now, genetics have entered the mix. An international team of researchers have published an exploration of the genomes of the tame, aggressive, and wild foxes, looking for clues that could illuminate the link between genes and domestication. The results point to where in the genome the most interesting differences show up, and they may help to identify genes that could be illuminating to study in more detail.
The oft controversial animal-rights group PETA has beef with the ostensibly animal-friendly Impossible Burger.
PETA, short for People for the Ethical Treatment of Animals, is fired up over the fact that the vegetarian burger’s maker, Impossible Foods, tested the safety of its faux patty on animals. Impossible Foods has openly noted that it conducted animal experiments—involving a total of 188 rats—to convince the Food and Drug Administration that the burger’s key, blood-like ingredient qualified as a safe food additive. The company was after a controversial FDA designation called “generally recognized as safe” or GRAS. The animals were sacrificed after the testing.
In a blistering blog post, PETA claimed the testing was “voluntary” and that Impossible Foods conducted the test after “disregarding advice from a PETA scientist who said that there’s no need to hurt and kill animals to test its burger.” To further scorch the burger’s name, PETA made the dubious suggestion that the burger could increase risks of cancer in consumers.
We tend to use "ice age" to mean a period where large ice sheets push south to what are now temperate regions. But from a geologist's perspective, even current conditions are part of an ice age, since large ice sheets exist at the poles. The term provides a contrast to what are called hothouse conditions, which the Earth has experienced for periods that were long enough to entirely melt the poles. The planet hasn't seen hothouse conditions for more than 2.5 million years.
But this week, headlines were full of discussion of a possible return of a hothouse Earth courtesy of climate change. The sudden worries weren't the product of any new research; instead, they were simply the product of a perspective some researchers had written on our current understanding of the climate, plus some potential risks associated with it. The perspective argued that there are multiple tipping points in the climate, and we can't rule out shooting past them even if we get emissions under control within a few decades.Hot hot hot
So how seriously should we view this risk, and why are scientists suddenly talking about it now?
Not so long ago, I attended a general physics conference where a lot of people were very excited about the Fermi Large Area Telescope. Fermi observed high-energy radiation from the galactic center and found an excess that was hard to explain. Might this be a long-awaited sign of dark matter? Early calculations seemed promising.
Now, it seems that the signal might due to pulsars and not dark matter.What did Fermi see?
The Fermi telescope watches the sky for gamma rays. These are photons with energies in the range of 10 million electron Volts (eV) up to about 300 billion eV. For comparison sake, light in the visible range is less than 10eV, while a standard X-Ray machine in a hospital has photons with an energy of about 2,000eV. So gamma rays are photons that pack a serious punch.
Six decades have passed since a University of Chicago physicist pondered why the tail of a comet, no matter the direction it traveled, always pointed away from the Sun. From this and other observations made by astronomers, Eugene Parker theorized that there must be some kind of stream of particles flowing away from the Sun. He called this the "solar wind."
It turns out that such a stream of charged particles does exist, a moving plasma of electrons, protons, and other particles that varies in density and speed. Over time, as observations mounted, astronomers moved from a position of skepticism about Parker's solar-wind idea to one of acceptance. Then, nearly 30 years ago, scientists launched their first mission, Ulysses, to make direct measurements of the phenomenon.
Astronomers have since come to realize the profound importance of this solar wind for our planet and the rest of the Solar System. For example, we now know that a few hundred million years after its formation, the early solar wind accelerated ions in the upper Martian atmosphere to an escape velocity, stripping the young planet of much of its atmosphere over time.
Welcome to Edition 1.12 of the Rocket Report! This week we have all kinds of stories about small rockets, the scoop on a Texas rocket company back from the dead, and some commercial crew launch dates that we may believe. Or maybe not.
As always, we welcome reader submissions, and if you don't want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets as well as a quick look ahead at the next three launches on the calendar.
New report quantifies surge in small rockets. In an updated report on the state of the small-satellite launch industry, Carlos Niederstrasser quantifies the increase in potential small launch vehicle contenders, defined as rockets capable of carrying up to 1000kg to low-Earth orbit. The growth has been remarkable. "The total number of efforts we are tracking... has increased from a mere 31 in 2015 to over 101 in 2018," he writes.
The neutron is a bit of a headache for physics. A neutron is an electrically neutral particle that helps glue protons together in the nucleus of atoms. Inside the atom, it is happily stable.
But a neutron alone is an unhappy beast. After about 10 minutes, it will emit an electron and an antineutrino and turn into a proton. The decay is all good, but there's a problem with the "about 10 minutes" part of things. In one set of experiments, we have determined that the half-life of a lonely neutron is 879.6s. But, in another set of experiments, we’ve found that the neutron has a half-life of 888s (these numbers might be slightly out of date now). The chance of these two being different by accident is now about one in 100,000.
Mars is mostly a red pile of mysteries. In its youth, it was clearly a very different place, even hosting oceans and lakes of liquid water. But apart from wondering whether anything living ever made Mars its home, figuring out how the Red Planet got warm enough to thaw all that water has turned out to be no small thing.
The evidence shows there probably wasn’t enough CO2 to warm up the early Martian greenhouse above the freezing point of water on its own. So might other gases have contributed? One option is simple hydrogen gas (H2). Although two-atom molecules like this typically aren’t greenhouse gases, hydrogen can absorb some infrared radiation in the moment it bounces off other molecules. And it can also react with CO2 to make some methane, which is a potent greenhouse gas.
But was there a source of hydrogen gas on Mars? A team led by Nicholas Tosca of the University of Oxford decided to follow a lead from the rocks beneath the wheels of the Curiosity rover—the mineral magnetite in a rock typical of lake-bottom sediments. The magnetite (which, not shockingly, is magnetic) would have formed within the mud, and that process can produce hydrogen.
The Environmental Protection Agency (EPA) has not been able to offer any scientific evidence for statements made by the agency's former Administrator Scott Pruitt when he went on CNBC in March 2017 and said that carbon dioxide was not known to be a major contributor to climate change.
During a live interview last year on Squawk Box, the administrator stated: “I would not agree that [carbon dioxide is] a primary contributor to the global warming that we see,” adding, “there’s a tremendous disagreement about the degree of the impact” of “human activity on the climate.”
Pruitt’s statements contradicted overwhelming scientific evidence as well as everything the EPA had published before he took office. In response, a group called Public Employees for Environmental Responsibility (PEER) formally requested any scientific documentation that might have informed Pruitt’s opinion, given the gravity of the about-face.
On Friday, when NASA announced the nine astronauts who would fly aboard the first commercial crew missions, Kathy Lueders sat among the audience clapping. Certainly for the manager of the space agency's commercial crew program, this was a happy day. But much hard work remains before the flights actually take place, and Lueders knows this more than anyone. Ultimately, she bears responsibility for ensuring that these men and women would have the safest possible flights.
“We’ve got to keep going,” she said later Friday, in an interview following the astronaut announcement ceremony. “I kind of feel like we’re having the party before the the flight.”
Manure from a high-density cattle farm that holds upward of 100,000 cows may have been the source of a deadly Escherichia coli strain that found its way onto romaine lettuce and caused a massive outbreak earlier this year. That’s according to a new hypothesis announced this week by the Food and Drug Administration.
The outbreak spanned from March to June, ultimately sickening 210 people in 36 states. Of those stricken, 96 were hospitalized, 27 suffered kidney failure, and five died.
The bacterium behind the outbreak was a particularly nasty strain of Shiga toxin-producing Escherichia coli O157:H7 that produces only Shiga toxin type 2 (Stx2), the more toxic of two types of toxins E. coli tends to carry. Stx2 causes cell death, triggers immune responses, and leads to the destruction of red blood cells, which can damage the kidneys.
A vicious species of tick originating from Eastern Asia has invaded the US and is rapidly sweeping the Eastern Seaboard, state and federal officials warn.
The tick, the Asian longhorned tick (or Haemaphysalis longicornis), has the potential to transmit an assortment of nasty diseases to humans, including an emerging virus that kills up to 30 percent of victims. So far, the tick hasn’t been found carrying any diseases in the US. It currently poses the largest threat to livestock, pets, and wild animals; the ticks can attack en masse and drain young animals of blood so quickly that they die—an execution method called exsanguination.
Key to the tick’s explosive spread and bloody blitzes is that its invasive populations tend to reproduce asexually, that is, without mating. Females drop up to 2,000 eggs over the course of two or three weeks, quickly giving rise to a ravenous army of clones. In one US population studied so far, experts encountered a massive swarm of the ticks in a single paddock, totaling well into the thousands. They speculated that the population might have a ratio of about one male to 400 females.
Spider silk is a bit of a dream material, stronger than steel by some measures yet incredibly light and flexible. Obtaining spider silk, however, is a bit of a nightmare, as most spider species are both extremely territorial and prone to cannibalism. While we have managed to identify the genes that are needed to produce silk, inserting those into other species hasn't worked out especially well, since silk formation depends on fairly precise mixtures of several proteins, as well as how the spider extrudes the fiber.
A Chinese group is now reporting some progress in overcoming at least some of these challenges. Their trick was to insert the genes into a domesticated species that already makes something like spider silk—specifically, the species that gave us the term silk. The new bit of genetic engineering has resulted in a silkworm that produces a hybrid silkworm/spider material that's not as tough but is a bit stretchier than native spider silk.More than meets the eye
If you've ever watched a spider spinning a web, silk production seems remarkably simple. But there's enough going on there to make a materials scientist dizzy. Most spiders make more than one kind of silk, as the properties that might make a good web might not be the same as the ones that would effectively arrest a fall after a spider has leapt off a tree branch. The differences come in part because silk is composed of multiple proteins, and some spiders have genes for different versions of these proteins. If they have some control over which starting materials go into their silk, a spider species can adjust its properties.
During family dinner, we have a tradition. Everyone has to summarize their day by describing three good events and, if necessary, one bad event. When my turn arrived at a recent dinner, I turned to my two eldest children and told them that my bad event was discovering that their math grades should have been higher.
I explained that I had just read a paper that claimed that people who enjoyed and were good at systemizing were also good at math. According to the paper, this was most strongly seen in people on the autism spectrum. “Hence, spawn-o-mine, I expect things to improve by at least one grade point.”
The paper in questing, entitled “Systemisers are better at maths,” represents the first attempt to try to test an old hypothesis and extend it to the general population. The hypothesis is that our brain uses two modules to try to make sense of the world. One systemizes: it looks for patterns and order and uses them to explain and predict the world. The second system is empathetic: it tries to predict and understand the world by walking in its shoes. One characteristic of autism spectrum disorder is the desire for order and patterns. This is often misinterpreted by saying that people on the spectrum lack empathy. This is simply wrong.
On Friday, Sen. Ted Cruz (R-Tex.) spent the morning at Houston's Johnson Space Center for a ceremony announcing the nine astronauts who will fly aboard NASA's first commercial crew missions. During the visit, Cruz burnished his space credentials, noting that nearly full funding for the commercial crew program by Congress coincided with his selection as chairman of the Senate committee that oversees NASA in 2015.
Recently, Sen. Cruz said that—while he does not oppose the Trump administration's plan to use the Moon as a proving ground for human exploration in deep space—NASA's goal must remain Mars, with human landings in the 2030s. "Let me be clear," he said at a committee hearing last month. "Mars is today the focal point of our national space program. And if American boots are to be the first to set foot on its surface, it will define a new generation. Generation Mars.”
With this statement in mind, Ars spoke to Cruz after Friday's ceremony in Houston. How did he think NASA could reach Mars by then, absent a large infusion of money?
Samir KC is on a mission to get people thinking differently about population growth. The basic idea of predicting future population size is so simple a child could do it. The reality of getting an accurate estimate is fiendishly complex, however, requiring intimate knowledge of how factors like education and migration will affect a given region.
“It’s very easy to do statistical extrapolation,” says KC, a professor at Shanghai University. But accuracy demands local expertise: “You need to understand a lot of things, and not everything is in the data. Only local demographers that are experts in that country can give you the right inputs.”
In a paper published in PNAS last week, KC and his colleagues show how predictions of India’s population over the next century can vary widely, depending on what data gets baked into the calculations. Population data plays a crucial role in planning for healthcare, education, and infrastructure (and in the longer term, climate change), so that variability has clear real-world implications.
Here's something you might be familiar with: a performance ends, the audience begins to applaud, and the sound becomes thunderous and continuous. But in your immediate neighborhood, everyone seems to be clapping at the same moment.
This synchronization is common in the classical world. Attach a few grandfather clocks to a wall and over the course of the day, their pendulums will start to swing in sync. In things like pendulums, the oscillators are not perfect—they lose energy over time. That energy is transmitted through vibrations to neighboring pendulums, where it is absorbed. The mutual emission and absorption of vibrations slowly brings the two pendulums into sync with each other.
Does synchronization work in a quantum system and, if so, how? This is the question a pair of researchers from Switzerland set out to answer.