Sommaire pour New Year 2021 de BBC Science Focus Magazine

On the rocks ILULISSAT, GREENLAND 2 SEPTEMBER This picture of Ilulissat’s port in Greenland raises the question of why exactly there is ice floating in the water. The answer is becoming the response to an increasing number of enquiries: climate change. Due to rising temperatures, 2021 saw Greenland experience the biggest melt of its ice sheet on record – enough to cover the entire state of Florida with five centimetres of water, according to Danish researchers. As parts of the ice sheet broke up, smaller chunks of ice ended up floating in Ilulissat’s port. As if that wasn’t concerning enough, for the first time in recorded history, rain fell onto the highest point of the Greenland ice sheet. A shot in the arm COVENTRY, UK 8 DECEMBER 2020 A round…

Two months after first taking to the skies, Spirit Of Innovation, Rolls-Royce’s allelectric plane, has hit what its makers claim to be a record-breaking top speed of 623km/h (387.4mph). The aircraft, which is part of the Rolls-Royce-led Accelerating the Electrification of Flight (ACCEL) project, smashed the previously held record for an electric plane by 213.04km/h (132mph). Rolls-Royce has submitted the data to the Fédération Aéronautique Internationale (FAI) – the World Air Sports Federation that controls and certifies world aeronautical and astronautical records – to confirm that it has broken the world record. Spirit Of Innovation achieved this feat thanks to a 400kW electric powertrain and a 6,480-cell, 750V battery. To put that into perspective, the battery has enough energy to juice up 7,500 smartphones. These drive a propeller that spins…

Around 1.2 million people in the UK are living with long COVID – a condition that sees them continue to experience COVID-19 symptoms for prolonged periods. The symptoms may persist for weeks, months and, in some cases, more than a year after the initial infection. The most common long COVID symptom reported is fatigue, which has led some to question whether the condition could be the same as chronic fatigue syndrome (CFS). Also referred to as myalgic encephalomyelitis (ME), CFS is a long-term condition that causes people to experience extreme fatigue, particularly after exercise, in addition to problems with sleeping, physical pain, and confusion known as brain fog. Scientists have yet to determine the cause of ME/CFS, but the onset of the condition in many patients follows infection with a…

For years, writers, scientists and entrepreneurs have shown us visions of our future relationships with computers and robots. These vary from the devastation of autonomous robots annihilating us, to the marvels of superhuman enhancement in robot suits. While the Terminator and Iron Man concepts push those ideas to the extreme, they highlight a clear choice in our use of technology. Should we aim for total automation with the target of greater safety and higher efficiency? Or should we aspire to augmentation – using technology to enhance our abilities without replacing us? As artificial intelligence and robotics mature enough to become integrated into everyday life, we need to start making this choice. We need to choose wisely, or we might just automate ourselves and the natural world out of existence. Humans…

WHY DO WE THINK THERE ARE BLACK HOLES IN GALAXY CENTRES AND NOT SUPERMASSIVE SUNS? The evidence for supermassive black holes (SMBHs) at the centres of most (if not all) galaxies, is both direct and indirect. Observations of ‘quasars’ – the extremely bright cores of distant galaxies – shows that they’re releasing up to a trillion times the energy of a typical star, all within a volume no bigger than the Solar System. The only mechanism that can explain this huge energy release is the conversion of gravitational energy into light by a SMBH. Any other kind of object, such as massive stars, simply cannot produce the observed amount of energy. Plus, it appears that stars of more than a few hundred solar masses are unlikely to form because radiation…

PENCILS AT THE READY! ACROSS 7 Temp, eccentric and unknown, used glass (5) 9 Washing – French articles – no longer wet (7) 10 Mission – include a large composition (7) 11 Small nuisance, getting a lot of land (5) 12 Endless flowers at home for old money (6) 13 Writer catching cold turned it into a setting agent (6) 16 Darrel’s off to the store (6) 17 Identify an index, say (6) 19 Sulked, getting a motorcycle (5) 21 A few lines on how to behave in pub (3,4) 22 Church items broken by drugs dealer (7) 23 Inventor of strange tales (5) DOWN 1 Firm clue about being forgiving (8) 2 Diet many reconsidered a very exciting thing (8) 3 Depressed by singular style of music (5) 4…

The Green Planet Sir David Attenborough travels the globe to gain a fresh understanding of the planet’s plant life. He meets the largest living things that have ever existed and the plants that hunt animals. BBC One Check Radio Times for details The Compass: Why We Play Humans are the pre-eminent playful species – from babies’ rattles through to bridge clubs for seniors. This series looks at play across cultures and through time. BBC World Service 5 January, 8pm Rethink: Population Amol Rajan is joined by expert guests to examine long-held assumptions about the number of people in the world. Are there simply too many of us everywhere, or could it be that some places just don’t have enough people? BBC Radio 4 3 January Check Radio Times for details…

From teenage social media stars to wizened old darts players, many of us are partial to a bit of bling. And according to a study carried out by researchers from Germany, Italy and Poland, it seems our ancient ancestors were too. The researchers used radiocarbon dating to determine that an intricately decorated ivory pendant found in a cave among animal bones is 41,500 years old. The object is the earliest known evidence of humans decorating jewellery to be found in Eurasia and could represent the emergence of the behaviour in human evolution, the researchers say. The pendant was first unearthed in 2010 during an excavation that took place in Stajnia Cave in southern Poland – a site known to have previously been inhabited by groups of Neanderthals and Homo sapiens.…

If all goes to plan, sometime in 2022 NASA’s Space Launch System rocket (SLS) will blast off from Cape Canaveral, Florida, for its maiden flight. The giant SLS rocket, fully 111.25m tall, is set to launch no earlier than February, but probably not until the summer, and will send an uncrewed capsule on a test mission around the far side of the Moon and back again. Known as Artemis 1, it will truly mark the beginning of humanity’s return to the Moon. The Artemis 2 mission, currently scheduled for May 2024, will repeat Artemis 1 but this time with a crew of astronauts. In their looping journey around the Moon, they’ll go further into space than any previous astronaut. Then comes the big one: Artemis 3, which will carry the…

An Asian megacity partially locked down because of pollution. Acres of farms in Africa destroyed by extreme weather. Ancient Arctic cultures disappearing with melting ice. This isn’t the future. It’s happening now. “I have a lot of problems with coughing as soon as I go out of the room,” says Mukesh Khare, professor emeritus at the Indian Institute of Technology Delhi. In November 2021 authorities in New Delhi closed schools, temporarily banned construction activities and advised people to work from home. A response to choking smog. In Africa, extreme weather has become far more common than it once was, from blistering heat and drought to erratic, torrential rainfall and the devastating floods that ensue, says Dr Catherine Nakalembe at the University of Maryland, in the US. “These extreme 1-in-30-year events…

WHICH IS BETTER: OPTIMISM OR PESSIMISM? Optimism and pessimism are fundamental traits of the human brain. With optimism, there’s the ‘Just World’ hypothesis, an ingrained assumption that the world is fair and that good actions will lead to good outcomes, and vice versa for bad ones. There’s also the ‘fading affect bias’, where memories for negative emotional experiences fade faster than positive ones. And then there’s the ‘planning fallacy’, a cognitive quirk where we constantly underestimate how long a task (such as driving to the airport) will take, regardless of how often we’ve done it before. These three traits alone show that optimism infuses our perception of past, present, and future. The same goes for pessimism, however. While our memories may skew positive, our emotion and attention systems show a…

WHAT IS THE FIBONACCI SEQUENCE? 1, 1, 2, 3, 5, 8, 13, 21… The Fibonacci sequence. Every number in the sequence is generated by adding together the two previous numbers. So the next Fibonacci number is 13 + 21 = 34. They are the simplest example of a recursive sequence where each number is generated by an equation in the previous numbers in the sequence. Hidden inside this sequence is another important number in mathematics: the golden ratio. Denoted by the Greek letter phi, it is a number like pi that has an infinite decimal expansion with no patterns. It starts phi = 1.61803… It’s defined as the ratio of a rectangle of dimensions A x B where the ratio A/B is equal to (A + B)/A. This is regarded…

In Star Wars: The Empire Strikes Back, Han Solo achieves every billionaire’s wildest dream by being frozen alive in cryogenic stasis – proof, as if it was needed, that he really is the coolest guy in the galaxy. Solo is frozen as an experiment by Darth Vader and Boba Fett (the latter returning to our screens in The Book Of Boba Fett, streaming on Disney+ from 28 December) to see if he would survive the ‘carbon freezing’ process. Fortunately, he does. But according to Gary Bryant, a physics professor at RMIT University in Melbourne, Australia, Solo wouldn’t have been so lucky in reality. “There’s no evidence of any cryoprotectant being injected into his body and there’s no human cell you can freeze without adding cryoprotectant first,” he says. This is…

More applicable advice, please I wondered if you could please pass on to Dr Michael Mosley the news that some of us are wheelchair users. He yet again writes articles on health and fitness, totally ignoring our existence. I’ve also just listened to his podcast, informing me that due to me not standing, I’ll die earlier from heart disease, diabetes and many other truly depressing things. Shall I just give up now? Tony Thanks for your letter, Tony; you make a very good point. My area of expertise does not include wheelchair users, who also tend not to feature much in the exercise research that I read. Time for that to change. I will try to do better in the future. Dr Michael Mosley, BBC Science Focus columnist WRITE IN AND…

The North Pacific Subtropical Gyre (or, as it’s more commonly known, the Great Pacific Garbage Patch) is a 79,000-tonne mass of plastic waste, covering an area of 1.5 million km2, floating between California and Hawai’i. It’s the largest of the world’s five trash-filled gyres. They form when plastic and other forms of waste are swept out to sea by surface currents, before being trapped and gathered together into great masses by rotating currents. Now, a study carried out by researchers at the Smithsonian Environmental Research Center (SERC), the University of Hawai’i and the Ocean Voyages Institute have found many coastal species – including anemones, hydroids and shrimp-like amphipods – making their homes on the North Pacific Subtropical Gyre’s mass of plastic waste. The researchers have dubbed these communities neopelagic, from…

The presence of pollutants in the air and water is associated with changes in the ratio of boys and girls born, a study led by Dr Andrey Rzhetsky of the University of Chicago, has found. It’s not clear whether these pollutants caused the change, however. Environmental factors can affect the likelihood of offspring being male or female in some non-human species. For example, in many reptiles and fish, the incubation temperature determines the sex of the eggs. Humans do have many folk tales about what affects the sex of a baby, from what the expectant parents eat, to how the baby is conceived. But although there have been some small studies, little is known for certain about what environmental factors can play a role in determining a baby’s sex. The…

Burnout is mentioned a lot these days. But what is it, exactly? A disease? A disorder? A driving-based video game? Actually, it’s none of these things (well, there is a video game but that’s not what we’re discussing here). Burnout is the phenomenon where an individual’s health (physical and mental) and functionality suffers due to them experiencing excessive stress for extended periods, specifically from their job. As such, it’s officially classed as an ‘occupational phenomenon’ (see ‘What is burnout?’, p41). There are those who may scoff at this. After all, hard work never hurt anyone, right? It’s character building! You’ve got to work hard if you want to succeed. You don’t get something for nothing, etc. Overall, there are many societal factors and assumptions that can, and do, lead people…

New Year means New Year’s resolutions and for lots of people that means taking up running or joining a gym in the hope that this will help them shed the kilos they’ve piled on over Christmas and the long months of COVID that came before. I won’t be joining them, because I hate the gym and I find that going for a run is nothing but pain, followed by relief when I stop. But I will continue to do brisk walks outdoors and sessions on my bike because I know they’re good for my overall health and may also cut my chances of developing depression. A few years ago I saw a study in the journal JAMA Psychiatry where researchers from Massachusetts General Hospital in the US analysed the health…

Deep beneath the salty ocean, the sea floor is cracked. Hot gases from the layers below bubble into the water, sustaining colonies of microbial life that are eking out an existence far from the sunkissed surface. This may sound like a scene from the bottom of Earth’s vast oceans, but it’s actually a possible description of Europa – one of the icy moons orbiting Jupiter. And thanks to the upcoming Jupiter Icy Moons Explorer (JUICE) mission, we may finally have the opportunity to find out how accurate that description is. Astrobiologists – scientists who look for signs of life beyond the confines of our planet – have long adhered to a simple mantra: follow the water. That’s because every living thing on Earth, from the tiniest bacterium to the mighty…

THE WINTER TRIANGLE WHEN: DECEMBER TO APRIL The Winter Triangle is what’s known as an asterism, basically an unofficial pattern in the night sky. Asterisms can be of any size, and can be contained within a single constellation or span several constellations (as is the case with the Winter Triangle). The triangle is formed from three bright stars visible in the winter sky; Betelgeuse in Orion the Hunter, Sirius in Canis Major the Great Dog and Procyon in Canis Minor the Little Dog. Betelgeuse is the red supergiant star that marks the northeast (upper left) corner of Orion’s main pattern. Despite being described as ‘red’, to the naked eye the star appears to be tinted orange. The centre of Orion is marked by three stars of similar brightness sitting in…