Sommaire pour June 2018 de BBC Science Focus Magazine

Planetary MOT Regarding your articles on whether we should intervene and do something directly to counteract climate change (April, p70), I agree with Peter Irvine that we should. If you have an accident and damage your car, you take steps to reduce the risk of it happening again, but you also fix the car. In the same way, we have had an accident with the Earth due to our own ignorance. Therefore, as well as taking steps to prevent further overheating we should fix the Earth and cool it down by geoengineering. Roy Caswell, Bolton Cheese it In response to Michael Mosley’s article ‘Is it okay to cut out cow’s milk?’ (May, p27), I find drinking milk and soft cheeses upsets my digestive system, as does anything with whey in…

Standing at up to 2.5 metres tall, with thick, muscular legs and sharp wolverine-like claws, the giant ground sloth was not an animal to be trifled with. But it seems that didn’t stop ancient humans from hunting them. Researchers at Bournemouth University and the University of Arizona have found a series of footprints indicating that our ancestors once stalked the ferocious animals. The team found the tracks, which date back around 12,000 years, on a remote salt flat in New Mexico’s White Sands National Monument. “This wasn’t just one human footprint and one sloth footprint. Somebody was walking along, purposely putting their feet in the sloth tracks,” said the University of Arizona’s Prof Vance Holliday. “It’s pretty amazing to see that sort of fleeting evidence of behaviour. You don’t see…

In the 70-plus years since the US dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki, several studies have examined the levels of radiation to which victims were exposed, using techniques ranging from longterm studies of mutation in the DNA of survivors, to measuring the luminescence of quartz grains in brick fragments. But now a team at the University of São Paulo (USP) in Brazil has successfully completed the first such study using actual human tissue. To do this, they employed a technique called ‘electron spin resonance spectrometry’. The research was conducted by postdoctoral researcher Angela Kinoshita, under the supervision of USP’s Prof Oswaldo Baffa, and builds upon 1970s research by Prof Sérgio Mascarenhas, also of the University of São Paulo. Mascarenhas discovered that exposure to radiation leaves…

If we ever master space tourism, Uranus is unlikely to become a favourite holiday destination. Researchers have learned that its upper atmosphere is permeated by hydrogen sulphide – the gas that gives rotten eggs their distinctive stench. A team of global researchers led by Prof Patrick Irwin from the University of Oxford used the eight-metre Gemini North Telescope on Hawaii’s Mauna Kea volcano to peer into the clouds that enshroud the planet. By using infrared spectroscopy, the study of how light and matter interact, they were able to determine the chemical composition of the gases that make up the clouds. “If an unfortunate human were ever to descend through Uranus’s clouds, they would be met with very unpleasant and odiferous conditions,” said Irwin. “But that’s not the worst of it.…

1. THE CLASSIC BUT DEADLY EINSTEINROSEN WORMHOLE This is the original wormhole version investigated by Einstein. It seems to offer a shortcut through space and time, and thus the possibility of effectively travelling faster than the speed of light. But the Einstein-Rosen bridge inside the wormhole immediately collapses and traps travellers inside, unless it’s supported by some strange form of material that generates negative energy. 2. THE ENTANGLED WORMHOLE The deadly collapse of the Einstein-Rosen bridge could be prevented if the black holes forming the entrance and exit of the wormhole have a special quantum property called ‘entanglement’. This requires the two black holes to be in direct contact with each other, consuming the radiation that each spews out. But while this keeps the Einstein-Rosen bridge intact, it also means…

You get back from work, crash out on the sofa and pick a track from your favourite playlist. Without moving from that spot you start heating up the oven to cook dinner before beginning a conversation with your friend who lives on the other side of town. You do all this without ever saying a word or pressing a single button. How did anyone get anything done before brain interfaces? The idea that we could run our lives from inside our heads is, obviously, a fantasy, but there are those who are attempting to make it a reality. In 2017, SpaceX and Tesla billionaire Elon Musk announced a new venture, Neuralink. Its aim: to build a high-bandwidth, implantable brain-computer interface that will put us permanently online and allow us to…

1 JUNOCAM (hidden in this image) Takes colour images 2 GRAVITY SCIENCE Studies Jupiter’s gravitational fields 3 SOLAR PANEL Three of these power the craft 4 JOVIAN ENERGETIC PARTICLE DETECTOR INSTRUMENT (JEDI) Detects highest energy particles 5 JOVIAN AURORAL  DISTRIBUTION EXPERIMENT (JADE) Detects particles and ions that cause the auroras 6 MICROWAVE  RADIOMETER (MWR) Measures microwave emissions 7 WAVES Measures radio waves 8 MAGNETOMETER Measures magnetic field’s direction and strength all around Jupiter 9 RADIATION VAULT The craft’s systems are encased in titanium to protect them from the high radiation levels around Jupiter 10 JOVIAN INFRARED AURORAL MAPPER (JIRAM) (underside of craft) Images auroras in infrared and measures thermal output of Jupiter’s upper layers…

If you’re a music enthusiast and you aren’t already aware of DACs (digital-to-analogue FRQYHUWRUV››Ŋ›FRPSDFW›GHYLFHV› RIIHULQJ›KL›Ɠ›TXDOLW\›DXGLR›LQ›WKH› palm of your hand – then you need to be. Once you experience listening to your favourite songs via a DAC, which delivers a quality of sound – known as high-resolution audio or Hi-Res – far better than that of a CD to both headphones and home stereo systems, you’ll wonder how you ever got by with a Walkman ›UHPHPEHU›WKRVH"››RU›HYHQ›DQ›L3RG›› Whether you’re at home, at work or on the go, DACs make the sound from smartphones, computers, WDEOHWV›DQG›ODSWRSV›LQƓQLWHO\›EHWWHU›› In fact, they improve all devices with a digital output, from DAB radios and TVs to games consoles and CD and DVD players, producing greater detail and dynamics. To put it simply, DACs give you more of…

Evolution is a process, not a property. There are people with genes that give them an advantage in certain environments – for example, some people are more resistant to tuberculosis. In a densely populated city with poor living conditions, that person would be better adapted and more likely to pass that gene on. But that’s not the same as being ‘more evolved’. If that person moves to a more affluent neighbourhood, or vaccination programs eradicate the disease altogether, then the genetic advantage would disappear. It’s a common mistake to look at animals that have not changed much physically over millions of years and conclude that they are somehow less evolved. In fact, evolution has affected them just as much as every other species. It’s just that the forces of natural…

How did this project get started? Ben Kacyra was one of the early inventors of the 3D laser scanner, and in 2001 he saw the Taliban destroy the 1,500-year-old Bamiyan Buddhas in Afghanistan. Ben realised that, using his 3D laser scanners, he could create a digital memory of similarly significant sites that could be used for blueprints, education or restoration. That’s what led him to establish CyArk, a non-profit that’s been working with governments and universities for a decade, documenting hundreds of sites. Why did Google Arts and Culture get involved? On one hand, we wanted to show the breadth of at-risk heritage sites, but we also wanted to create a platform for CyArk to share their open data and create 3D models of these amazing sites. We want people…

As part of the rainforest’s vast recycling system, foraging ants will soon find any carcasses and dismantle them at speed. Photographer Nick Garbutt found this newly deceased tarantula on the forest floor in Borneo’s Danum Valley, laid it on a piece of white paper, and took these photos over the course of four hours. When a foraging ant finds a dead animal, she will lay a pheromone trail to guide her nestmates back to the carcass. When the ants arrive, they’ll cut off scraps with their jaws and carry them back to their nest. Ants are responsible for removing more than half the food resources and decaying matter from the rainforest floor, helping to keep the ecosystem healthy. “When we think of scavengers we tend to think about large, dead…

Two articles in your March issue came together to solve two kitchen questions for me in a delicious way. I love hot chocolate and am sold on the health benefits of turmeric. In Michael Mosley’s article on turmeric (March, p28), he reported that cooking with it is much better than taking a supplement. Adding fat and heating it up might make turmeric easier for the body to absorb. I’ve tried making ‘golden milk’ with turmeric but it’s hard to get the turmeric to dissolve without extra steps. A few pages later in the issue was Helen Czerski’s article on how to get cocoa powder to dissolve to make good hot chocolate (p87). Bingo! I added a teaspoon of turmeric to a tablespoon of cocoa powder in a pan with a…

Faced with a potential threat, a mouse will respond in one of three ways: either freezing (making it harder for the predator to detect it), ducking into the nearest shelter, or running for its life. Now, a team at Stanford University School of Medicine has identified two clusters of nerve cells in a mouse’s brain that control this response by sending signals to different regions. As similar circuitry is found in human brains, the discovery could potentially lead to new ways of treating phobias, anxiety disorders and post-traumatic stress disorder, they say. The researchers placed mice into a specially designed tank that simulated the approach of a bird of prey by displaying an expanding dark disc above the mice’s heads, representing the shadow of a predator as it swooped overhead.…

Accident and trauma victims with type O blood – around 45 per cent of the population – may be at significantly higher risk of dying than people with similar injuries who have less common blood types, according to new research carried out at Tokyo Medical and Dental University Hospital. “Loss of blood is the leading cause of death in patients with severe trauma, but studies on the association between different blood types and the risk of trauma death have been scarce,” Said Dr Wataru Takayama, lead author of the paper in the journal Critical Care. “We wanted to test the hypothesis that trauma survival is affected by differences in blood types.” The team studied the records of the 901 patients treated for severe trauma at two Japanese medical centres in…

More than 420 reptile species live in the mountains of Madagascar, but an expedition carried out by researchers from the Zoologische Staatssammlung in Munich has yielded a surprise: three new brightly coloured species of chameleon. The rainbow-hued Calumma uetzi was found in the remote mountains on northern Madagascar and is at its most impressive when trying to attract a mate. The males turn a flashy shade of yellow, streaked with violet and red, and if the female is unimpressed, she’ll darken her own skin to almost black. Females from another new species, Calumma juliae, were found in a threatened 15-hectare forest fragment beside one of the island’s main roads. “We hope that this area can be protected as soon as possible,” said researcher David Prötzel. “Recent imagery from Google Earth…

How life came into existence is one of science’s greatest mysteries, but a new experiment at the American Institute of Physics suggests that a handful of basic elements and some radiation might be all you need. A paper in the Journal Of Chemical Physics describes how researchers working in cryogenic conditions coated ice with molecules of carbon dioxide, methane and ammonia, and then exposed the ice to a stream of low-energy electrons, or LEEs. This mimics conditions in space, where such basic molecules can be detected in the ice found on bodies such as comets or moons, where they are subject to bombardment by various forms of radiation including gamma rays, X-rays, LEEs and solar wind particles. Following the LEE onslaught, the researchers used a spectrometry technique called ‘temperature programmed…

Want to stream real-time video of wildebeest migrating across the Serengeti, a tropical storm picking up speed in the Pacific, or the long line of traffic you’re sitting in? That’s the idea behind EarthNow, a company that’s recently received backing from Microsoft founder Bill Gates and Softbank CEO Masayoshi Son. According to EarthNow’s founder and CEO Russell Hannigan, “EarthNow is ambitious and unprecedented, but our objective is simple; we want to connect you visually with Earth in real-time. We believe the ability to see and understand the Earth live and unfiltered will help all of us better appreciate and ultimately care for our one and only home.” EarthNow cites a tonne of possible positive applications, like catching illegal fisherman, detecting forest fires as they start, tracking whale migrations, observing conflict…

Hefty, high-end fitness watches don’t just tell you how far you’ve run. They can now tell you how much altitude you've gained, how long you;ve spent dreaming and critique your golf swing. They can track heart rate at your wrist, elimating the need for a sweaty chest strap, and provide you with round-the-clock data. with so many good, low-cost fitness trackers available, we wanted to find out whether expensive models, with all their extras, are worth the price. We pit Garmin Fenix 5, a multisport model from the king of fitness watches, againts the Suunto Spartan Sport Wrist HR Baro, A feature-packed option from a stylish up-and-comer. WHAT YOU NEED TO KNOW HOW OPTICAL HEART-RATE SENSORS WORK 9TKUV›JGCTV›TCVG›UGPUQTU›WUG›QRVKEU›VQ›OGCUWTG›[QWT›RWNUG›› $NQQF›CDUQTDU›C›NQV›QH›NKIJV››UQ›HNWEVWCVKQPU›KP›NKIJV›NGXGNU› can be used to measure the rhythm of the blood flowing…

While theorists wrestle with the possibility of cosmic wormholes, researchers in Spain have succeeded in making one in the lab – by swapping gravity for magnetism. The result is a wormhole that takes magnetic fields in at one place and then allows them to magically reappear somewhere else. Alvaro Sanchez and his colleagues at the Autonomous University of Barcelona pulled off this feat by creating a sphere made from special conducting materials that respond to magnetic fields in different ways. Carefully arranged in layers, these materials have the effect of modifying the way empty space transmits magnetic fields. The result is a device that acts as a wormhole where a magnetic field enters on one side of the sphere, completely disappears once inside, and then appears again on the other.…

nce in a while, it’s worth looking up. Our busy lives mean that we’re tuned into streets, buildings, cars and kitchens – a rich world of detail at eye level or below. But we often neglect the vast amount of free space above our heads. Our atmosphere is mostly just air and water, but the visual variety of the sky is astonishing, especially when it comes to the clouds. How does such colour and complexity come from these simple ingredients? The answer is that clouds give us a sneak peek at the optical traffic above our heads – the light that wouldn’t normally make it to our eyes. There is so little to a cloud. They’re made of water droplets and ice crystals that are typically a hundredth of a…

As a child, Japanese engineer Masaaki Nagumo watched animated human-controlled robots in battle in the popular Japanese series Mobile Suit Gundam. Inspired by the show, he’s created LW-Mononofu, an 8.5-metre-tall robot that tips the scales at more than seven tonnes. Climb into LW-Mononofu’s cockpit, and you’ll find monitors and levers that control the robot’s arms and legs. It can move its upper body and walk forwards and backwards, but with a top walking speed of less than 1km/h, it’s not winning any races. That bazooka-like right arm might come in handy in combat though; it fires sponge balls at around 140km/h (87mph). Don’t expect to see LW-Mononofu charging around the Japanese countryside, though. Nagumo accidentally built the robot higher than its warehouse’s door, so it can’t leave without being dismantled.…

It’s time to remap the cosmos. ESA’s Gaia mission has produced the most detailed picture yet of the night sky, pinpointing the positions of nearly two billion stars. Launched in December 2013, the Gaia space observatory is creating a three-dimensional map of the Milky Way. After an initial data release in 2016, this second phase covers the period from 25 July 2014 to 23 May 2016, and increases the number of surveyed stars from two million to almost 1.7 billion. It also ramps up the accuracy, with a maximum precision equivalent to someone on the Earth being able to spot a coin on the surface of the Moon. As well as their positions, Gaia also measured the brightness and colour of most of the stars, the velocity across the sky…

Why is plastic such a big environmental problem? A plastic bottle normally comes from oil and it’s made of two components: one is called ethylene glycol, a very common chemical; the other is terephthalic acid. You link those together with an ester bond, and lots of ester bonds in a row generate a long chain – a polyester. Polyethylene terephthalate or PET [a common type of polyester] – the stuff plastic bottles are made of – is incredibly difficult to break down. When chemists made it around 50 years ago, they couldn’t have realised it would end up being a scourge in our oceans, lasting for hundreds of years. Where was the plastic-eating enzyme discovered? In 2016, a Japanese group spectacularly found bacteria in a recycling dump that were essentially…

Some songs feel like they’ve been written just for you. They might send a shiver down your spine, give you goosebumps or even move you to tears. Songs like these seem to reach inside you and touch something that nothing else can. And for that very reason, they might be able to treat some of the symptoms of Alzheimer’s disease. “People with dementia are confronted by a world that’s unfamiliar to them, which causes disorientation and anxiety,” said Jeff Anderson, who, along with his colleagues at the University of Utah Health, is investigating the potential for music-based treatments for Alzheimer’s. A recent study by the team suggests that songs a dementia sufferer finds emotionally resonant may alleviate their anxiety by increasing brain activity. Songs that provoke an emotional response tap…

When Chuck Yeager broke the sound barrier in the Bell X-1 in 1947, a sonic boom rang out that battered the eardrums of anyone underneath the plane’s 20-second supersonic flight path. Now, NASA has just announced funding for its latest X-plane, a commercial jet capable of flying at those same supersonic speeds (faster than the speed of sound), without the disturbing the peace below. NASA has awarded Lockheed Martin a $247.5m (£183m approx) contract to build a working example of a prototype it’s been working on for a few years: the Low Boom Flight Demonstrator. It has a long, pointy nose and small, aerodynamic wings, which should minimise the pressure waves that create the noise at supersonic speeds. NASA plans to start flying the plane by 2022, with testing over…

It takes half a million human hours to build a typical Tokyo skyscraper, and Japan’s labour crisis is making that a difficult feat. Now, though, Shimizu Corporation is developing robots to take care of as many of those hours as possible. At the Robot Laboratory in Tokyo, Shimizu Corporation is testing three new machines. The Robo-Welder has a robotic arm that it uses to weld steel, and the Robo-Buddy is a multipurpose robot that can install ceiling panels and construct floors. The third robot, Robo-Carrier, can lug one ton of plasterboard to a designated location, using lasers to navigate and recognise obstacles. Unfortunately, building site regulations mean that Robo-Carrier can only work on sites at nights and during the weekend. Robots are a feature in most types of manufacturing, with…

Ever since a trip through a wormhole was first portrayed in 2001: A Space Odyssey 50 years ago, the idea of them has captured the public imagination. And small wonder: they’re the ultimate form of cosmic travel: a way of zipping across galaxies in an instant. But while wormholes have become a staple of science fiction, among scientists they’ve been a source of endless frustration. Not because the idea is ridiculous, but because it isn’t. The astonishing fact is that wormholes are a natural consequence of current theories of gravity, and were investigated by Einstein himself over 80 years ago. Ever since, researchers have been trying to find out if such a bizarre theoretical possibility could be a reality. And now they have made a major breakthrough – one which…

In classical mythology, the god Jupiter surrounded himself in clouds to keep his antics hidden from view. Only his wife, Juno, could see through the veil to his true nature. And so it is with the NASA spacecraft of the same name. The secrets of the formation of the whole Solar System lie below Jupiter’s all-encompassing clouds, just waiting to be discovered. Theories about our Solar System formation all begin with the collapse of a giant cloud of gas and dust, otherwise known as a nebula, the majority of which formed the Sun. Like the Sun, Jupiter is mostly hydrogen and helium, so it too must have formed early on, capturing most of the leftover material after our star formed. How this happened, however, is unclear. Did a massive planetary…

Every barbecue, picnic and garden party needs a good soundtrack. Even al fresco dining can be improved with some good music to set the scene. Danish high-end loudspeaker specialist DALI has produced a new portable speaker that will satisfy all your outdoor music needs. 7KH›.$7&+›LV›WKH›EUDQGōV›ƓUVW› compact Bluetooth portable speaker. It combines innovative Danish design with the latest audio technology, creating an active loudspeaker that delivers incredibly rich sound from a compact – and super stylish – chassis. The high-quality audio is the result RI›D›&ODVV›'›DPSOLƓHU››WZR›››PP› soft-dome tweeters, and two 3.5-inch woofers located under the extruded aluminium hood. This winning combo gives the audio some real punch, but keeps things UHƓQHG››SHUIHFWO\›EDODQFHG›DQG›SLWFKHG› – even at the highest volumes. Plus, the WZR›VRXQG›SURƓOHV››RQH›IRU›IUHHVWDQGLQJ› SOD\›DQG›RQH›WR›UHŴHFW›VRXQG›EDFN› from a wall, mean you can maintain the exceptional audio quality…

Are electric cars finally about to catch on? Manufacturers are now convinced that they can build electric cars with a comparable range and speed to their petrol counterparts. The key is developing cheaper and lighter lithium-ion batteries that can store ever more energy. The technology still isn’t mainstream: in the UK, just 1.5 per cent of cars come with plugs. However, in Norway, where there are huge tax breaks and perks like being able to use bus lanes, it’s up to 29 per cent. This shows that, with government incentives, people are willing to start driving electrics, and sales are predicted to spike when the price falls to the level of a petrol equivalent – forecast to happen in the early 2020s. How do electric cars compare with petrol cars?…

01 EXPLORE BAGAN OPEN HERITAGE FREE ARTSANDCULTURE.GOOGLE.COM/PROJECT/CYARK The ancient city of Bagan was once the political, economic and cultural centre of Myanmar, with 10,000 Buddhist temples, pagodas and monasteries dotting the landscape. But the city lies in an active earthquake zone, and today, just over 2,000 of those buildings remain. Thanks to a new project called Open Heritage, you can use your smartphone, tablet, desktop computer or VR headset to fly over or wander through Bagan and explore its archaeological sites and ancient art. CyArk, a digital preservation non-profit, has collected 3D laser scans and photographic data in over 100 historically significant sites. They’ve partnered with Google Arts and Culture to create a platform to open source that info, and create models that anyone can experience, starting with Bagan. Over…