Having devoted his life to the conundrums of the cosmos, Prof Stephen Hawking has left behind a mystery of his own amid the eclectic contents of his former office. From a report: The Cambridge cosmologist, who died in 2018 at the age of 76, treasured a blackboard that became smothered with cartoons, doodles and equations at a conference he arranged in 1980. But what all the graffiti and in-jokes mean is taking some time to unravel. The blackboard -- as much a perplexing work of art as a memento from the history of physics -- goes on display for the first time on Thursday as part of a collection of office items acquired by the Science Museum in London.

The hope for Juan-Andres Leon, the curator of Stephen Hawking's office, is that surviving attenders of the conference on superspace and supergravity held in Cambridge more than 40 years ago swing by and explain what some of the sketches and comments mean. "We'll certainly try and extract their interpretations," Leon said. Joining the blackboard in a temporary display called Stephen Hawking at Work is a rare copy of the physicist's 1966 PhD thesis, his wheelchair, a formal bet that information swallowed by a black hole is lost for ever, and a host of celebrity memorabilia, including a personalised jacket given to him by the creators of the Simpsons for his many appearances on the show.

Our nearest neighboring star, Proxima Centauri, may be harboring an extensive solar system, as scientists believe they've found a third planet orbiting it. From a report: It's a find that re-emphasizes just how commonplace planets outside our Solar System may be -- and it provides us with a third possible world nearby to study and potentially explore. Located a little more than 4 light-years from Earth, Proxima Centauri has long captured the imagination of scientists and sci-fi enthusiasts as a prime place to visit if we ever venture far outside our Solar System. The celestial object became even more intriguing in 2016 when astronomers found a planet orbiting around it. Called Proxima b, the planet is located in the star's habitable zone, where temperatures may be just right for water to pool on the surface. Just a few years later, a second planet, called Proxima c, was discovered around the star, too. With the discovery of this third likely exoplanet, called Proxima d, Proxima Centauri is possibly home to a wide array of worlds. While we do not have the means to travel to Proxima Centauri yet in any kind of reasonable time frame, these planets might be the first places we'd visit if we ever do develop such a capability. For now, their close proximity to Earth makes them prime candidates for follow-up study and observations. Astronomers say they could help us in our ever-evolving quest to understand how planets form around distant stars.

An anonymous reader quotes a report from Gizmodo: Researchers in Canada say they've come up with two simple physical techniques to help prevent a common cause of dizziness and fainting. In a small trial, they found that these maneuvers, which involve nothing more than moving your lower limbs, could effectively reduce the symptoms of initial orthostatic hypotension (IOH), a condition that temporarily leaves people light headed when they stand up. [...] Though many people can experience IOH without ever registering it as a big problem, some sufferers can have repeated or severe enough episodes of IOH that it routinely affects their daily functioning. Study author Satish Raj, a heart rhythm cardiologist at the University of Calgary, and his colleagues have often seen these sorts of patients at their dysautonomia and fainting clinic. And they wondered if there was something more they could offer these patients besides lifestyle changes like drinking more water or medications.

As he explains it, when people stand up, blood flow normally shifts downward to below our chest. But in IOH, this change seems to be accompanied by a reflex, triggered by the activation of muscles as we stand up, that causes blood vessels to open widely -- and it's this combination that then causes the rapid but temporary drop in blood pressure. Based on Raj's team's earlier work, as well as other research, they hypothesized that people with IOH could short-circuit this process by activating the reflex early or by tensing the lower limb muscles as they stood, somewhat mitigating the blood pressure drop.

To test this out, they recruited 22 volunteers with IOH to try out both of the techniques they developed. One method involved pre-activating the muscles behind the reflex from a sitting position, done simply by raising the knees one at a time for up to 30 seconds. The other asked people to stand and then tense up their lower limbs, by crossing their legs and clenching their thighs and butt. As a control, the volunteers would also stand up normally. Compared to the control condition, on measures of both the volunteers' circulation and their self-reported symptoms, people's IOH improved after doing either technique. And Raj's patients in the clinic have anecdotally reported similar success after adopting the strategies. The team's findings were published Wednesday in the journal Heart Rhythm.

Elon Musk's satellite internet service Starlink just got dealt an expensive blow -- the company's currently estimating that 40 of the 49 Starlink satellites it launched on February 3rd will be destroyed because of a geomagnetic storm. The Verge reports: The storm caused "up to 50 percent higher drag than during previous launches," keeping the deployed satellites from reaching their proper orbit around the Earth. And while Starlink tried to fly them "edge-on (like a sheet of paper)" to reduce that drag, it now looks like as many as 40 of them will burn up in the Earth's atmosphere instead of reaching their destinations. SpaceX recently crossed the 2,000 satellite launch milestone, and has plans to launch 12,000 if not a great many more -- so losing 40 of them might not be a huge deal in the grand scheme of things. Still, that's the vast majority of an entire Falcon 9 rocket's Starlink launch capacity burning up in the atmosphere.

An electric shock might be just the thing to persuade a cloud to produce some rain. New research suggests that supercharging a cloud could increase the attractive forces between droplets and help raindrops to grow. Have we finally found the recipe for making rain? From a report: Electric charge is all around us. Thunderclouds literally crackle with it, but even the air we breathe has some charged aerosols and droplets in it. Giles Harrison, a meteorologist at the University of Reading, and colleagues have been investigating the electric charge of drops in non-thunderstorm clouds. In calculations led by Maarten Ambaum and published in Proceedings of the Royal Society A, they show that the greater the variation in charges, the stronger the attraction between droplets. "This advances our understanding of how charge influences drop growth and brings a new aspect to answering the age-old question: why does it rain?" says Harrison. Last year Harrison and his colleagues, who have been funded by the United Arab Emirates to research rain enhancement, flew drones equipped with ionisers into clouds and experimented with releasing positive and negative charges into the air. The new results will help them fine-tune these experiments, potentially to find ways to hasten the formation of rain where it is needed.

European scientists say they have made a major breakthrough in their quest to develop practical nuclear fusion -- the energy process that powers the stars. tomhath writes: The UK-based JET laboratory has smashed its own world record for the amount of energy it can extract by squeezing together two forms of hydrogen. If nuclear fusion can be successfully recreated on Earth it holds out the potential of virtually unlimited supplies of low-carbon, low-radiation energy. The experiments produced 59 megajoules of energy over five seconds (11 megawatts of power). This is more than double what was achieved in similar tests back in 1997. It's not a massive energy output - only enough to boil about 60 kettles' worth of water. But the significance is that it validates design choices that have been made for an even bigger fusion reactor now being constructed in France. "The JET experiments put us a step closer to fusion power," said Dr Joe Milnes, the head of operations at the reactor lab. "We've demonstrated that we can create a mini star inside of our machine and hold it there for five seconds and get high performance, which really takes us into a new realm."

A group of Brown University physicists has developed a technique that can potentially generate millions of random digits per second by harnessing the behavior of skyrmions -- tiny magnetic anomalies that arise in certain two-dimensional materials. Phys.Org reports: Their research, published in Nature Communications, reveals previously unexplored dynamics of single skyrmions, the researchers say. Discovered around a half-decade ago, skyrmions have sparked interest in physics as a path toward next-generation computing devices that take advantage of the magnetic properties of particles -- a field known as spintronics. [...] Skyrmions arise from the "spin" of electrons in ultra-thin materials. Spin can be thought of as the tiny magnetic moment of each electron, which points up, down or somewhere in between. Some two-dimensional materials, in their lowest energy states, have a property called perpendicular magnetic anisotropy -- meaning the spins of electrons all point in a direction perpendicular to the film. When these materials are excited with electricity or a magnetic field, some of the electron spins flip as the energy of the system rises. When that happens, the spins of surrounding electrons are perturbed to some extent, forming a magnetic whirlpool surrounding the flipped electron -- a skyrmion.

Skyrmions, which are generally about 1 micrometer (a millionth of a meter) or smaller in diameter, behave a bit like a kind of particle, zipping across the material from side to side. And once they're formed, they're very difficult to get rid of. Because they're so robust, researchers are interested in using their movement to perform computations and to store data. This new study shows that in addition to the global movement of skyrmions across a material, the local behavior of individual skyrmions can also be useful. For the study, which was led by Brown postdoctoral fellow Kang Wang, the researchers fabricated magnetic thin films using a technique that produced subtle defects in the material's atomic lattice. When skyrmions form in the material, these defects, which the researchers call pinning centers, hold the skyrmions firmly in place rather than allowing them to move as they normally would.

The researchers found that when a skyrmion is held in place, they fluctuate randomly in size. With one section of the skyrmion held tightly to one pinning center, the rest of the skyrmion jumps back and forth, wrapping around two nearby pinning centers, one closer and one farther away. The change in skyrmion size is measured through what's known as the anomalous Hall effect, which is a voltage that propagates across the material. This voltage is sensitive to the perpendicular component of electron spins. When the skyrmion size changes, the voltage changes to an extent that is easily measured. Those random voltage changes can be used to produce a string of random digits. The researchers estimate that by optimizing the defect-spacing in their device, they can produce as many as 10 million random digits per second, providing a new and highly efficient method of producing true random numbers.

NASA on Monday announced that it has selected the aerospace company Lockheed Martin to build the Mars Ascent Vehicle (MAV), a small rocket that will launch pristine Red Planet samples back toward Earth a decade or so from now. Space.com reports: Mars Sample Return is a joint effort of NASA and the European Space Agency (ESA). The project is already well underway, thanks to NASA's Perseverance rover, which landed on the Red Planet in February 2021.The six-wheeled robot has collected a handful of samples thus far and will eventually snag several dozen more, if all goes according to plan. The next big steps are scheduled to come in the mid-2020s, with the launch of two additional missions -- the NASA-led Sample Retrieval Lander (SRL) and ESA's Earth Return Orbiter (ERO).

SRL will deliver an ESA "fetch rover" and the MAV to the Martian surface. The fetch rover will carry the collected samples from Perseverance -- or the spot(s) where Perseverance has cached them -- to the MAV, which will then launch them into orbit around the Red Planet. A container holding the samples will then meet up with the ERO, which will haul it home to Earth, perhaps as early as 2031. Once the samples are down on the ground, scientists in well-equipped labs around the world will study them for signs of ancient Mars life, clues about the planet's evolutionary history and other topics of interest, NASA officials have said. [...] The newly announced MAV contract has a potential value of $194 million, NASA officials said in today's statement. The contracted work will begin on Feb. 25 and run for six years. During this time, Lockheed Martin will build multiple MAV test units as well as the flight unit. "Committing to the Mars Ascent Vehicle represents an early and concrete step to hammer out the details of this ambitious project not just to land on Mars, but to take off from it," Thomas Zurbuchen, the associate administrator for science at NASA Headquarters, said in a statement. "We are nearing the end of the conceptual phase for this Mars Sample Return mission, and the pieces are coming together to bring home the first samples from another planet," Zurbuchen added. "Once on Earth, they can be studied by state-of-the-art tools too complex to transport into space."

sciencehabit shares a report from Science.org: Three men paralyzed in motorcycle accidents have become the first success stories for a new spinal stimulation device that could enable faster and easier recoveries than its predecessors. The men, who had no sensation or control over their legs, were able to take supported steps within 1 day of turning on the electrical stimulation, and could stroll outside with a walker after a few months, researchers report today. The nerve-stimulating device doesn't cure spinal cord injury, and it likely won't eliminate wheelchair use, but it raises hopes that the assistive technology is practical enough for widespread use.

For now, sending commands to the device is cumbersome. Users must select their desired movement on a tablet, which sends Bluetooth commands to a transmitter worn around the waist. That device must be positioned next to a 'pulse generator' implanted in the abdomen, which then activates electrodes along the spine. Setting up to use the stimulation takes 5 to 10 minutes. But the next generation of devices should allow users to activate the pulse generator by giving voice commands to a smartwatch. The company behind the technology plans to test this newer mobility system in a multisite clinical trial of 70 to 100 participants that the team hopes will lead to U.S. regulatory approval. The researchers reported their findings in the journal Nature Medicine.

magzteel shares a report: For almost five years, an international consortium of scientists was chasing clouds, determined to solve a problem that bedeviled climate-change forecasts for a generation: How do these wisps of water vapor affect global warming? They reworked 2.1 million lines of supercomputer code used to explore the future of climate change, adding more-intricate equations for clouds and hundreds of other improvements. They tested the equations, debugged them and tested again. The scientists would find that even the best tools at hand can't model climates with the sureness the world needs as rising temperatures impact almost every region. When they ran the updated simulation in 2018, the conclusion jolted them: Earth's atmosphere was much more sensitive to greenhouse gases than decades of previous models had predicted, and future temperatures could be much higher than feared -- perhaps even beyond hope of practical remedy. "We thought this was really strange," said Gokhan Danabasoglu, chief scientist for the climate-model project at the Mesa Laboratory in Boulder at the National Center for Atmospheric Research, or NCAR. "If that number was correct, that was really bad news." At least 20 older, simpler global-climate models disagreed with the new one at NCAR, an open-source model called the Community Earth System Model 2, or CESM2, funded mainly by the U.S. National Science Foundation and arguably the world's most influential climate program. Then, one by one, a dozen climate-modeling groups around the world produced similar forecasts. "It was not just us," Dr. Danabasoglu said.

The scientists soon concluded their new calculations had been thrown off kilter by the physics of clouds in a warming world, which may amplify or damp climate change. "The old way is just wrong, we know that," said Andrew Gettelman, a physicist at NCAR who specializes in clouds and helped develop the CESM2 model. "I think our higher sensitivity is wrong too. It's probably a consequence of other things we did by making clouds better and more realistic. You solve one problem and create another." Since then the CESM2 scientists have been reworking their climate-change algorithms using a deluge of new information about the effects of rising temperatures to better understand the physics at work. They have abandoned their most extreme calculations of climate sensitivity, but their more recent projections of future global warming are still dire -- and still in flux. As world leaders consider how to limit greenhouse gases, they depend heavily on what computer climate models predict. But as algorithms and the computer they run on become more powerful -- able to crunch far more data and do better simulations -- that very complexity has left climate scientists grappling with mismatches among competing computer models.

"Scientists have made the first steps to develop an atlas of world cancer, hoping it will bring us closer to a cure," reports the Telegraph.

"A map showing stark differences in the incidence of 10 types of cancer between Spain and Portugal has sparked a race to pinpoint causes and risk factors people should avoid." It shows huge differences for people living only a short distance apart, sometimes across the border between Spain and Portugal, and others occurring within the same country. Scientists say it will take years to solve the puzzle completely but are confident that the map provides the pieces. There are easier questions and more complex riddles. But it all points to environmental factors — as opposed to genetics — playing a major role in causing cancers.

The lung cancer map tells a clear story of far higher levels of smoking tobacco in Spain than in Portugal, with the latter country showing a consistent hue of dark blue for a lower risk of mortality, while Spain has large areas lit up in red, at least on the map representing men. Twenty per cent of Spanish adults are daily smokers, compared with just over 11 per cent in Portugal. But the data from cancer of the larynx, also linked to smoking, tells a vastly different story, with a high mortality risk for men shown straddling the border in southern Portugal and south western Spain, as well as patches in the north of both countries. "The lung cancer and smoking connection is very clear, so why in other cancers that have a strong link with tobacco are we seeing such surprising differences?" asks Pablo Fernández-Navarro, the lead co-ordinator of the atlas from the Spanish side.

"This is what is so fantastic. If whole countries had uniform levels of mortality, the maps would be in plain colours. Given that it is not the case, now we have to investigate and explain these differences, eliminating one factor after another," Fernández-Navarro told The Telegraph.

In the case of larynx cancer, the Spanish epidemiologist says the map confirms that smoking is by no means the only risk factor, and that other elements must also be at work, from alcohol intake to levels of pollutants such as asbestos or petrochemicals in the environment.
Thanks to Slashdot reader Bruce66423 for sharing the link.

Scientific American reports: These are boom times for astronomers hunting black holes. The biggest ones — supermassive black holes that can weigh billions of suns — have been found at the centers of most every galaxy, and we have even managed to image one. Meanwhile, researchers now routinely detect gravitational waves rippling through the universe from smaller merging black holes. Closer to home, we have witnessed the dramatic celestial fireworks produced when the Milky Way's own supermassive black hole and its more diminutive cousins feed on gas clouds or even entire stars. Never before, though, have we seen a long-predicted phenomenon: an isolated black hole drifting aimlessly through space, born and flung out from the collapsing core of a massive star.

Until now.

Scientists have announced the first-ever unambiguous discovery of a free-floating black hole, a rogue wanderer in the void some 5,000 light-years from Earth. The result, which appeared January 31 on the arXiv preprint server but has not yet been peer-reviewed, represents the culmination of more than a decade of ardent searching. "It's super exciting," says Marina Rejkuba from the European Southern Observatory in Germany, a co-author on the paper. "We can actually prove that isolated black holes are there." This discovery may be just the start; ongoing surveys and upcoming missions are expected to find dozens or even hundreds more of the dark, lonely travelers. "It's the tip of the iceberg," says Kareem El-Badry from the Harvard-Smithsonian Center for Astrophysics, who was not involved in the paper....

The odds of seeing such an event for an isolated black hole were slim, but given that millions of stellar-mass black holes are predicted to be drifting through our galaxy, some might turn up in sufficiently broad and deep surveys of the sky.... This black hole's mass offers further evidence that astrophysicists' formation models are correct — that solitary black holes can rise from the ashes of especially hefty stellar progenitors.... Rogue stellar-mass black holes, long predicted but only now observationally confirmed, might well be sufficiently common in our galaxy to support demographic studies of their population. Pinning down their true abundance, masses and other properties could shore up our still-incomplete theories of stellar evolution — or reveal important new gaps in our understanding.
"If confirmed, this is a very exciting discovery!" adds the astronomy column at Syfy.com. "We know those black holes are out there, and this research points to how we can find them."

The precise astrometry was partly performed using the Hubble Space Telescope over a six-year interval, according to the research paper.

CNN reports that wastewater-based epidemiology "has proven to be so reliable in dozens of pilot projects across the U.S. that the government has invested millions to create the National Wastewater Surveillance System, or NWSS, a network of 400 testing sites spread across 19 states that is coordinated by the U.S. Centers for Disease Control and Prevention."

The pilot programs have already been "quietly operating behind the scenes, generating data for public health departments across the country, since September 2020." For the first time, the CDC has published data that looks at how much coronavirus is turning up in the country's wastewater. It added this testing data to its Covid-19 dashboard. Tests show that there's been a decrease in the amount of virus at two-thirds of the 255 sites reporting data from the latest 15-day period.

The NWSS includes 400 sites overall, and more than 500 more will begin submitting data in the coming weeks, the CDC says.... [G]enetic material from the virus gets flushed down the toilet into the wastewater stream, where it can be detected by the same kinds of tests labs use to detect the virus from nasal swabs: real time polymerase chain reaction tests, or RT-PCR. This kind of testing is highly sensitive. It can pick up the presence of the virus when just one person out of 100,000 in a given area, or sewershed, is infected. And because wastewater testing doesn't depend on people to realize they're sick and seek out a test, or even to have symptoms at all, it's often the earliest warning a community has that wave of Covid-19 infections is on the way. The CDC estimates that...the samples typically turn positive in an area four to six days before clinical cases show up.

"As long as people are using a toilet that's connected to a sewer, we can get information on those cases in that community," said Amy Kirby, a CDC microbiologist who leads the NWSS project... [But] this kind of testing can't signal when a community is free from the virus because the threshold of detection — how many people have to be positive in an area to show up in a water sample — isn't known. For these reasons, the CDC says, wastewater surveillance is best used along with case-based surveillance....

Kirby says wastewater monitoring will be around long after Covid is gone, too. By the end of the year, the CDC plans to expand the number of pathogens tracked on the dashboard to include influenza, a fungal superbug called Candida auris, and foodborne threats like E. coli and salmonella.

An anonymous reader shares a report from the University of Bonn in North Rhine-Westphalia, Germany: A few years ago, a novel measurement technique showed that protons are probably smaller than had been assumed since the 1990s. The discrepancy surprised the scientific community; some researchers even believed that the Standard Model of particle physics would have to be changed. Physicists at the University of Bonn and the Technical University of Darmstadt have now developed a method that allows them to analyze the results of older and more recent experiments much more comprehensively than before. This also results in a smaller proton radius from the older data. So there is probably no difference between the values -- no matter which measurement method they are based on. The study appeared in Physical Review Letters.

[...] Using this method, the physicists reanalyzed readings from older, as well as very recent, experiments -- including those that previously suggested a value of 0.88 femtometers. With their method, however, the researchers arrived at 0.84 femtometers; this is the radius that was also found in new measurements based on a completely different methodology. So the proton actually appears to be about 5 percent smaller than was assumed in the 1990s and 2000s. At the same time, the researchers' method also allows new insights into the fine structure of protons and their uncharged siblings, neutrons. So it's helping us to understand a little better the structure of the world around us -- the chair, the air, but also the stars in the night sky.

Engineers from the University of Delaware developed a method for effectively capturing 99 percent of carbon dioxide from the air using an electrochemical system powered by hydrogen, a press statement reveals. Interesting Engineering reports: The new system, outlined in a new paper in the journal Nature Energy, was actually born out of a setback in another research project. The team behind the new technology was originally working on hydroxide exchange membrane (HEM) fuel cells, a more affordable and environmentally friendly alternative to traditional acid-based fuel cells. While working on that technology, the team was faced with a serious obstacle. HEM fuel cells, they found, are very sensitive to carbon dioxide in the air, making it hard for the batteries to function properly.

Fast forward a few years later, and the researchers that once tried to combat the effects of carbon dioxide on HEM fuel cells are now using it to our advantage. "Once we dug into the mechanism, we realized the fuel cells were capturing just about every bit of carbon dioxide that came into them, and they were really good at separating it to the other side," said Brian Setzler, a co-author on the paper. The team leveraged the built-in "self-purging" process seen in HEM fuel cells to create a carbon dioxide separator that could be placed upstream from their fuel cell stacks. "It turns out our approach is very effective. We can capture 99 percent of the carbon dioxide out of the air in one pass if we have the right design and right configuration," said study lead and UD Professor Yushan Yan.

Today, the team has a more compact system that is capable of filtering greater quantities of air. According to the researchers, their soda can-sized early prototype device is capable of filtering roughly 10 liters of air per minute and of removing about 98 percent of CO2. What's more, they found that a smaller electrochemical cell measuring 2 inches by 2 inches could be used to continuously remove roughly 99 percent of CO2 found in the air flowing at a rate of approximately two liters per minute. The team's prototype is designed to scrub CO2 out of a vehicle's exhaust, though it could also be used for a number of other applications, including aircraft, spacecraft, and submarines.

An anonymous reader quotes a report from Ars Technica: The Falcon 9 reached a notable US milestone in January, equaling and then exceeding the tally of space shuttle launches. During its more than three decades in service, NASA's space shuttle launched 135 times, with 133 successes. To put the Falcon 9's flight rate into perspective, it surpassed the larger shuttle in flights in about one-third of the time. There is no way to know how many missions the Falcon 9 will ultimately fly. At its current rate, the rocket could reach 500 flights before the end of this decade. However, SpaceX is also actively working to put its own booster out of business. The success of the company's Starship project will probably ultimately determine how long the Falcon 9 will remain a workhorse. Nevertheless, it seems likely the Falcon 9 will fly for a long time yet. That is because it now provides the only means for US astronauts to get into space. And while NASA's deep-space Orion vehicle and Boeing's Starliner spacecraft should come online within the next couple of years, the Falcon 9 rocket and Crew Dragon spacecraft will very likely remain the lowest risk, and lowest cost, means of putting humans into orbit for at least the next decade.

Speaking of safety, this is where the Falcon 9 rocket has really shone of late. Since the Amos-6 failure during its static fire test, SpaceX has completed a record-setting run of 111 successful Falcon 9 missions in a row. It probably will be 112 after Thursday. There are only two other rockets with a string of successful flights comparable to the Falcon 9. One is the Soyuz-U variant of the Russian rocket, which launched 786 times from 1973 to 2017. The other is the American Delta II rocket, which recently retired. (Eventually, the Atlas V rocket could also exceed 100 consecutive successes before its retirement later this decade.) According to Wikipedia, amid its long run, the Soyuz-U rocket had a streak of 112 consecutive successful launches between July 1990 and May 1996. However this period includes the Cosmos 2243 launch in April 1993. This mission should more properly be classified as a failure. According to noted space scientist Jonathan McDowell, the control system of the rocket failed during the final phase of the Blok-I burn, and the payload was auto-destructed.

Taking this failure into account, the Soyuz-U had a run of 100 successful launches from 1983 to 1986. This happens to be the exact same number of consecutive successes by the Delta II rocket, originally designed and built by McDonnell Douglas and later flown by Boeing and United Launch Alliance. Overall the Delta II rocket launched 155 times, with two failures. Its final flight, in 2018, was the rocket's 100th consecutive successful mission. So the Falcon 9 has now exceeded both the Soyuz-U and Delta II rockets for consecutive mission successes, and apparently its low flight insurance costs reflect this. What seems remarkable about all of this is that the Falcon 9 amassed this safety record at the very same time SpaceX was experimenting with and demonstrating reuse. At the time of the Amos-6 failure in 2016, the company had yet to re-fly a single Falcon 9 first stage. Now it has pushed some of its boosters to fly 11 flights, and SpaceX has never lost a mission on a reused first stage, even though founder Elon Musk and other officials have explicitly said they are pushing the technology to find its limits.

An anonymous reader quotes a report from The New York Times: When you take a whiff of something, odor molecules sail inside your nose where they bind to proteins -- called olfactory receptors -- on cells that line your nasal cavity. These receptors trigger signals that your brain interprets as one or many smells. A team of scientists has identified the olfactory receptors for two common odor molecules: a musk found in soaps and perfumes and a compound prominent in smelly underarm sweat. The research team also discovered that more recent evolutionary changes to these olfactory receptors make people less sensitive to those odors. So if you're one of the fortunate ones who isn't overwhelmed by body odor, you should probably thank evolution. The work was published in PLoS Genetics on Thursday.

Olfactory receptors can be traced back hundreds of millions of years and are believed to be present in all vertebrates. Humans have around 800 olfactory receptor genes, but only about half of them are functional, meaning they'll be translated into proteins that hang out in the nose and detect odor molecules. But within a functional gene, minor variations can cause changes in its corresponding receptor protein, and those changes can massively affect how an odor is perceived. [...] Trans-3-methyl-2-hexenoic acid is considered one of the most pungent compounds in underarm sweat. Galaxolide is a synthetic musk often described as having a floral, woody odor that's used in perfumes and cosmetics, but also things like kitty litter. The research team was able to identify olfactory receptor variants for those odors and, in both cases, people with the more evolutionarily recent gene variant found the odors significantly less intense. The galaxolide findings were particularly striking, with some participants unable to smell the musk at all. "It's really rare to find an effect that's as large as what we saw for this one receptor on the perception of the musk odor," said Marissa Kamarck, a neuroscientist at the University of Pennsylvania who was an author of the study.

[Hiroaki Matsunami, a molecular biologist at Duke University who was not involved in the research] views this work as another example of human olfaction being more complex than people initially thought. He said that, although the major findings in the study involved just two scents, they're adding to evidence that "odorant receptors as a group have extraordinary variety." The authors think their findings support a hypothesis that has been criticized that the primate olfactory system has degenerated over evolutionary time. Kara Hoover, an anthropologist at the University of Alaska Fairbanks who was not involved in this research but who studies the evolution of human smell, is not convinced by that hypothesis in the first place. "Why is reduced intensity assumed to be degradation?" she asked. "Maybe other things are becoming more intense or odor discrimination is improving. We know too little to make these conclusions." For Dr. Hoover, these findings stirred up other evolutionary questions. "Our species is really young," she said. "Why this much variation in such a short period of time? Is there an adaptive significance?"

The International Space Station (ISS) will continue its operations until 2030 before heading for a watery grave at the most remote point in the Pacific, Nasa confirmed in a new transition plan this week. The Guardian reports: More than 30 years after its 1998 launch, the ISS will be "de-orbited" in January 2031, according to the space agency's budget estimates. Once out of orbit the space station will make a dramatic descent before splash landing in Point Nemo, which is about 2,700km from any land and has become known as the space cemetery, a final resting place for decommissioned space stations, old satellites, and other human space debris. Also known as the "Oceanic Pole of Inaccessibility" or the "South Pacific Ocean Uninhabited Area," the region around the space cemetery is known for its utter lack of human activity. It's "pretty much the farthest place from any human civilization you can find," as NASA put it. Nasa said it plans to continue future space research by buying space and time for astronaut scientists on commercial spacecraft.

A group of researchers at University College London (UCL) have used an MRI scanner to guide a tiny magnetic "seed" through the brain to heat and destroy cancer cells. Interesting Engineering reports: The novel breakthrough cancer therapy, which has been tested on mice, is called "minimally invasive image-guided ablation," or MINIMA, according to the study published in Advanced Science. It consists of ferromagnetic thermoseeds, which are basically 2mm metal spheres, that are guided to a tumor using magnetic propulsion generated by an MRI scanner and then remotely heated to kill nearby cancer cells. If this technique translates to humans, it could help to combat difficult-to-reach brain tumors by establishing "proof-of-concept" for precise treatment of cancers like glioblastoma, the most common form of brain cancer, and prostate, which could benefit from less invasive therapies.

The UCL researchers demonstrated the three major components of MINIMA to a high level of accuracy: precise seed imaging, navigation through brain tissue using a customized MRI system (tracked to within 0.3 mm accuracy), and eradicating the tumor in a mouse model by heating it. The researchers used an MRI machine to direct 2mm diameter metal spheres, which were implanted superficially into the tissue, then navigated to the tumors. Then, they were heated to destroy the cells. "Using an MRI scanner to deliver a therapy in this way allows the therapeutic seed and the tumor to be imaged throughout the procedure, ensuring the treatment is delivered with precision and without having to perform open surgery," explained lead author Rebecca Baker at the UCL Centre for Advanced Biomedical Imaging, in a press release. "This could be beneficial to patients by reducing recovery times and minimizing the chance of side effects."

An anonymous reader quotes a report from Phys.Org: A team of researchers from the University of Massachusetts Amherst recently announced in the Proceedings of the National Academy of Sciences that they had engineered a new rubber-like solid substance that has surprising qualities. It can absorb and release very large quantities of energy. And it is programmable. Taken together, this new material holds great promise for a very wide array of applications, from enabling robots to have more power without using additional energy, to new helmets and protective materials that can dissipate energy much more quickly.

"Imagine a rubber band," says Alfred Crosby, professor of polymer science and engineering at UMass Amherst and the paper's senior author. "You pull it back, and when you let it go, it flies across the room. Now imagine a super rubber band. When you stretch it past a certain point, you activate extra energy stored in the material. When you let this rubber band go, it flies for a mile." This hypothetical rubber band is made out of a new metamaterial -- a substance engineered to have a property not found in naturally occurring materials -- that combines an elastic, rubber-like substance with tiny magnets embedded in it. This new "elasto-magnetic" material takes advantage of a physical property known as a phase shift to greatly amplify the amount of energy the material can release or absorb.

A phase shift occurs when a material moves from one state to another: think of water turning into steam or liquid concrete hardening into a sidewalk. Whenever a material shifts its phase, energy is either released or absorbed. And phase shifts aren't just limited to changes between liquid, solid and gaseous states -- a shift can occur from one solid phase to another. A phase shift that releases energy can be harnessed as a power source, but getting enough energy has always been the difficult part. "To amplify energy release or absorption, you have to engineer a new structure at the molecular or even atomic level," says Crosby. However, this is challenging to do and even more difficult to do in a predictable way. But by using metamaterials, Crosby says that "we have overcome these challenges, and have not only made new materials, but also developed the design algorithms that allow these materials to be programmed with specific responses, making them predictable."