Indholdsfortegnelse for March 2019 i BBC Science Focus Magazine

Here it is, your first issue of the new-look BBC Science Focus. What’s changed? We listened to your feedback and have tried to give you more of what you love. As a result, Discoveries (p15) is bigger and better, providing more insight and analysis into the news that matters. The same goes for Q&A (p75), where the changes we’ve made will let us answer your brilliant questions in more detail than before. I’d also like to introduce our new section, Reality Check (p32), where we look at the science behind the headlines. In a world where measles is making a comeback, and politicians ignore climate change because it’s snowing, it seemed vital to provide a voice of reason to cut through the nonsense. This month, we look at what you…

A moment of reflection I’m currently serving with the RAF in the Falkland Islands, and have never missed a copy since I started a subscription some 17 years ago. I managed to put a few to one side before coming out here, and much to my displeasure I noticed that in issue 326 (September) the question about whether opposing mirrors produce infinite reflections (bit.ly/mirrors_reflection) won Question Of The Month, and was awarded a Skullcandy headset... Well, I sent that very same question in some 12 or 13 years ago, but I wasn’t given the honour of Question Of The Month nor did I win a prize for ingenuity, originality or even for my handwriting ... If spending six months away from my family in the middle of nowhere defending this…

When it comes to treating brain tumours, surgeons face a major problem: how do you remove cancerous cells without damaging the healthy tissue that surrounds them? Now, a team at Georgia Institute of Technology think they have the answer – trick the tumour cells into moving in a certain direction by luring them, Pied Piper-style, out of the brain. For the past five years they’ve been developing a device they call a “tumour monorail”, and after successful trials in rats they have just been awarded ‘breakthrough status’ by the US Food and Drug Administration (FDA). The device is essentially a long, thin tube made of fine, flexible fibres that is fed through a narrow opening connecting the brain’s left and right hemispheres. It takes advantage of the fact that tumour…

WHAT DID THEY DO? Researchers at Rockefeller University, led by Leslie Vosshall, gave diet drugs to female Aedes aegypti mosquitoes. WHY DID THEY DO THAT? Unlike male A. aegypti mosquitoes, the females feed on human blood. In the process of feeding, they spread pathogenic viruses like yellow fever, dengue, Zika and chikungunya. As the flies are becoming more resistant to insecticides, the researchers think that artificially suppressing their appetites might provide an alternative way to reduce the spread of disease. WHAT DID THEY FIND? The drug inhibited biting and feeding behaviours when the mosquitoes were exposed to the scent of a human or a source of warm blood. “When they’re hungry, these mosquitoes are supermotivated. They fly toward the scent of a human the same way that we might approach…

WHAT IS 5G? 5G is the fifth generation of mobile networks, following on from 2G, 3G and 4G. But while the move from 3G to 4G was all about speeds, 5G is about so much more. Sure, 5G is extremely quick, but it’s also stable and reliable, with characteristics that will allow it to form the underlying communication networks for connected vehicles, virtual reality worlds and robotics systems. The new network’s greater capacity will allow these bandwidth-hungry applications to run simultaneously, without having the knock-on effect of slowing down the network for other users. HOW DOES IT WORK? Like its predecessors, 5G is transmitted via radio waves. It will use some frequencies that are in the 4G range, as well as a higher frequency, called millimetre wave technology. The latter…

LAZY LANGUAGE LEARNERS Scientists at the University of Bern played a made-up language and its interpretations (such as ‘tofer’ = ‘key’ and ‘guga’ = ‘elephant’) to napping test subjects. Upon waking, they couldn’t recall the words’ meanings, but were able to categorise them (they knew a tofer was something small, and a guga was something large). TRYPANOPHOBES Got a fear of needles? Help may be on the way. A team at MIT has developed a pill the size of a pea that can inject a shot of drugs directly into the stomach lining after being swallowed.…

WHY DOES THE MAGNETIC NORTH POLE MOVE, AND WHY IS IT MOVING SO QUICKLY? The magnetic field is created by the liquid outer core that starts about halfway to the centre of the Earth. You’ve got this large, convecting layer of liquid metal and, as it moves, it creates the magnetic field, but it also drags the field with it. The reason the magnetic north pole is moving is because, we think, a fast jet of liquid has formed – a sort of jet stream – at the high latitudes up around northern Canada, and it’s pushing the magnetic field in this area rapidly. If you look back at how the magnetic north pole has moved in the last hundred years or so, you’ll see that from 1900 to 1990…

Houseplants aren’t just good décor: they are also a fast and effective way to clean up the air in your home. Researchers at the State University of New York studied five different houseplants to measure their efficiency at removing volatile organic compounds (VOCs) from the air. For a good all-rounder, choose a bromeliad. These plants managed to strip more than 80 per cent of all pollutants out of the air over the course of 12 hours. But if you run a nail salon, try a dracaena: these removed 94 per cent of acetone, the source of the powerful smell of nail varnish remover. Even if you’re not the green-fingered sort, you can always buy an air purifier to do the job instead – but make sure the device you choose…

@ShuhBillSkee Prof Andy Przybylski is the director of the Oxford Internet Institute. His research has been used to inform government reports on screen time effects. @OrbenAmy Amy Orben is a PhD student who researches effects of screen time on behaviour and mental wellbeing using large datasets. @CJFerguson1111 Prof Chris Ferguson’s research largely shows that violent video games have negligible effects on our behaviour. @DrKowert Dr Rachel Kowert is a psychologist and video games expert who has produced an excellent parents’ guide to understanding the effects that video games can have on us.…

It’s 2011. I’m in New Zealand for the first time, speaking at a literary festival about my most recent book. I’m discombobulated. I’m hungry for something familiar. Something to make being this far away feel okay. I loaded up the recently launched Google Now on my phone. It read my location, the weather and time. It compared that information with what it knew I liked based on past searches, and predicted what it thought I might like, based on search results of people similar to me. When I arrived at the suggested cafe, it was exactly in my comfort zone: exposed brickwork, white subway tiles, lots of greenery, bare wood tables, Edison bulbs. I had to wait for a table, so I dived into a book that I’d brought along…

If being happy is good for your health, helping you to fight off a cold and even prolonging your life, what is happiness? We know when wefeelhappy but can we actually detect happiness inside us? Dr Mark Holder, an associate professor of psychology at the University of British Columbia in Canada, decided to find out. “I had conceptualised happiness as the opposite of depression; so if you think of a continuum, the more you move away from depression, the happier you are.” So he asked some of his students to provide him with spit and urine samples and he measured levels of two hormones – cortisol and serotonin. After all, antidepressant drugs are designed to increase serotonin levels, and high levels of cortisol have also been linked to depression. The…

DR ALASTAIR GUNN Astronomer, astrophysicist DR HELEN SCALES Oceans expert, science writer ALEX FRANKLINCHEUNG Environment/ climate expert DR CHRISTIAN JARRETT Neuroscientist, science writer DR PETER J BENTLEY Computer scientist, author DR EMMA DAVIES Chemistry expert, science writer PROF ALICE GREGORY Psychologist, sleep expert LUIS VILLAZON Science/tech writer DR KATE ADAMS GP, journalist JULES HOWARD Zoologist, science writer CHARLOTTE CORNEY Zoo director, conservationist PROF ROBERT MATTHEWS Physicist, science writer…

I CAN’T STOP SMELLING MY SOCKS. AM I WEIRD? Not at all. Many of us like to whiff smelly things. It’s a form of what psychologists call ‘benign masochism’. The minor thrill of a nasty smell has been likened to the adrenaline rush we get from rollercoasters. Even though we’ve been warned that the experience will be unpleasant, we know it won’t be seriously harmful, so it provides a way for us to test out experiences and emotions in safety. Be careful when it comes to your socks, though – they might be harbouring fungal spores. A 37-year-old man in China was hospitalised last year with a lung infection attributed to his compulsive sock-sniffing. LV MY FRIENDS CALL ME ‘HUMPTY DUMPTY’ BECAUSE I’M ALWAYS FALLING OVER. CAN MY CLUMSINESS BE…

WHAT HAS PHYSICS GOT TO DO WITH THE ORIGIN OF LIFE? Seventy-five years ago, the famous quantum physicist Erwin Schrödinger gave a series of lectures and then wrote a book called What Is Life? Schrödinger was one of the founders of quantum mechanics, which is probably the most successful scientific theory we have. At a stroke it explained the nature of matter, all the way from atomic nuclei up to stars. So here was an architect of a theory so powerful that it explained the nature of matter. Could it also explain the nature of life? In his lectures, Schrödinger had to admit that, in spite of his brilliance, he still found life very baffling, looked at through the eyes of a physicist. At the level of individual atoms inside…

AMAZON ECHO Amazon has “pretty much got it nailed” when it comes to security, according to security expert Ken Munro (see interview, right). Moreover, a big company like Amazon has a reputation on the line, so you’re more likely to get your privacy concerns addressed than if you went with a new start-up. They’ve even been asked to hand over Alexa recordings to a judge in a murder case, but won’t do so “without a valid and binding legal demand properly served on us.” Security-wise, they’ve got your back. £69.99, AMAZON.CO.UK PHILIPS AVENT SCD630/26 VIDEO BABY MONITOR Baby monitors have been hacked by criminals, allowing footage from the devices to be streamed online. This one randomly changes the frequency the monitor is using to communicate, making it harder to hack.…

CHELTENHAM SCIENCE FESTIVAL 4 – 9 JUNE 2019 Fascinating talks and hundreds of free hands-on activities exploring wellbeing, wonders of the everyday world, mysteries of the universe and cutting-edge technology set in a free-to-enter Festival village in beautiful gardens. cheltenhamfestivals.com/science01242 850270 NORWICH SCIENCE FESTIVAL 18 – 26 OCTOBER 2019 Be inspired and intrigued at Norwich Science Festival this October! Celebrate exploration, innovation and ground-breaking research through thought-provoking talks, sensational shows and hands-on experiments at The Forum and Norwich venues. norwichsciencefestival.co.uk science@theforumnorwich.co.uk SUMMER SCIENCE EXHIBITION 1 – 7 JULY 2019 The Royal Society’s annual Summer Science Exhibition offers a mind-blowing experience for anyone curious about the latest technological and scientific advances. This free, blockbuster exhibition gives visitors unparalleled access to the researchers at the frontiers of science. Discover what the city of…

We’ve all experienced that irritating feeling of being distracted from the task at hand. But don’t be too hard on your butterfly mind: our brains have evolved, for good reason, to be distractible. We prize an ability to concentrate, but we need our attention to be flexible. If we focused too tightly we’d miss the creaking floorboard that signifies an intruder, or the whiff of smoke that announces fire. Attention has proven to be much more complicated, and weirder, than it seems. If you look closely at something – a photo of a landscape, say – you probably feel that you are noticing everything when, in fact, you’re taking in just a few bits at a time. This is because the more you concentrate, the narrower your view becomes. Inattentional…

Take notes and re-read them frequently. Repetition prevents information from being forgotten because it reignites and helps solidify the neural networks that hold memories. Try the Cornell note-taking method ( lsc.cornell.edu/notes.html ): 1. Record the information of a lecture as notes 2. Devise exam-type questions based on your notes 3. Answer your questions aloud, without consulting your notes 4. Reflect on your notes and your answers 5. Review your older notes regularly Revise for an exam in a room scented with something unusual then put a bit of this scent on your wrist before the exam and sniff it if you are stuck. This is particularly effective if the material has an emotional component: in a 2011 study at Utrecht University, volunteers watched an emotionally engaging film in a room…

PETE ETCHELLS We’ve all read the headlines: screen time is bad for us. But as psychologist and video games researcher Pete reveals, the story is much more nuanced. p36 HAYLEY BENNETT Science writer Hayley explores the incredible engineering that’s allowing people to transport rockets, telescopes and Antarctic research bases. p40 MARCUS CHOWN Author and broadcaster Marcus meets the researchers who are peering deeper into the Universe than ever before. p46 ALEKS KROTOSKI Aleks, presenter of the Digital Human on BBC Radio 4, explores how we’ve become ensnared by the web’s taste makers. p58…

Moon musings With regard to the article A New Race To The Moon Has Begun in your current edition, (February, p32) the science-fiction writer, the late Robert A Heinlein, once wrote: “The laws of nature are not the exclusive property of any group or society; they belong to anyone prepared to make use of them.” At the time, he was warning of the danger of the US space program losing ground to the Japanese, but it is at least equally relevant to the Chinese. As various commentators have pointed out, a few centuries ago, the Chinese Empire sent a number of expeditions – utilising ships significantly larger than their Western equivalents – down the eastern coast of Africa. Had the expeditions continued, Western and Chinese ships could have met, somewhere…

PATIENT, LOVE THYSELF Self-compassion can calm the heart and reduce feelings of distress, according to a recent study. Volunteers were played recordings that either told them to be kind to themselves, or were more critical. Those who heard the first set had reduced heart rates. The others’ hearts beat faster and they started to sweat. According to the University of Exeter researchers, being kind to yourself relaxes the body, which can boost the immune system and help with healing.…

#MassExtinction A global review of the world’s insects carried out by Australian researchers has found that 40 per cent of all species are threatened with extinction in decades.Nearly all insects could die out within a century, they say. Chris Packham @ChrisGPackham Greed for money is driving this apocalypse. The agrochemical giants’ power over the farming lobbyists who have brainwashed the farmers into thinking that we need poisons for produce. It’s a lie and earth is dying @DaveGoulson @GeorgeMonbiot @ExtinctionR George Monbiot @GeorgeMonbiot The greatest cause of this collapse is the way we produce our food. The ecological implosion caused by current farming and fishing methods is happening even faster than climate breakdown #Allblacks Former Irish international rugby player Emmet Byrne claimed that the All Blacks are genetically superior to the…

3.8 years The metabolic age that a woman’s brain appears to be younger than a man’s of the same chronological age, according to a study at Washington University. It could explain why women tend to stay mentally sharp longer than men. 99.99% The percentage of bacteria killed in 10 litres of water by a new purification material. When exposed to light, the substance releases oxygen-based chemicals that destroy microbes. 10 hours, 33 minutes and 38 seconds The length of a day on Saturn, as determined using data recorded by NASA’s Cassini probe.…

CHIP LOVERS British chips were 2.5cm shorter last year, thanks to extreme heatwaves starving UK potato plants of water over the summer and preventing them from growing to their usual size, according to a study at the University of Leeds. CITY DRIVERS The limited availability of spaces and high parking fees in cities could make it cheaper for autonomous vehicles to cruise around slowly rather than finding somewhere to park. According to transportation planner Adam Millard-Bell at the University of California, Santa Cruz, this means they’ll be adding to urban gridlock rather than reducing it.…

Chinese scientists have cloned gene-edited primates for the first time. The team at Shanghai’s Institute of Neuroscience initially used gene-editing to disable a gene in macaque monkeys that helps control their sleep-wake cycle. In humans, mutations in this gene are linked to hypertension and depression. The macaques immediately displayed sleep loss, anxiety and ‘schizophrenia-like’ behaviours. The researchers then cloned one of the monkeys, creating five macaques with identical genomes. To clone an animal, DNA is taken from an adult cell and placed in an egg which has had its genetic material removed. When stimulated to form an embryo, the resulting monkey is identical to the original. Using genetically identical animals helps scientists because it reduces variation between the individuals in experiments. It is for similar reasons that human identical twins…

YOU’RE PRESENTING BLUE PLANET LIVE WITH LIZ BONNIN AND STEVE BACKSHALL THIS MONTH. WHAT’S THE PLAN? There are two objectives: we want to engage the audience, and we need to get close to the animals and be able to tell their stories. We’re also doing an overview of oceanographic health. For instance, the Japanese have said they’re going to resume commercial whaling in their own waters. I thought, Japan, relatively small island, so the waters they have control of will be relatively small. But I was wrong. They cover an area the size of India, and within that area there is an extraordinary diversity of whales. These sorts of issues, whether it’s welfare, exploitation, overfishing, pollution, plastics, will all be on our agenda. WHERE WILL YOU BE PRESENTING FROM? I…

Nobody likes catching a cold. But it seems that we all have a pretty effective weapon that can reduce our chances of getting one – being happy. In a study published back in 2003, over 300 volunteers in the US were knowingly infected with a virus responsible for the common cold. They were then monitored for symptoms over the next five days. The results were clear. Those with the most positive outlooks on life were three times less likely to develop cold symptoms than those who were the least happy. Other studies have reached similar conclusions. A positive mental attitude can have long-term health benefits too. In the US, the autobiographies of 180 Catholic nuns in their 20s and 30s were analysed by psychologists to see what they revealed about…

*TAKE A BATH A study at the University of Freiburg last year concluded that a warm bath twice a week is better than physical exercise for combating depression. **SWITCH TO SOAP Shower gel requires five times more energy than soap to produce, and the packaging it comes in uses 20 times more energy to manufacture. ***TURN IT DOWN As well as stripping more of your skin’s natural oils, a very hot shower brings blood to the skin’s surface, which might make you itchy. This encourages you to scratch your scalp when the skin has lost the oils that keep it flexible, potentially leading to infected abrasions.…

Sheep produce an oily substance called lanolin from their skin to waterproof their fleece. Lanolin is a mixture of up to 20,000 long-chain hydrocarbon compounds. The fleece from one sheep contains about 275ml of lanolin. Before the fleece can be spun into wool, the lanolin must be removed by washing in hot water and then centrifuging. The extracted lanolin is used in hundreds of different applications, from nipple cream to the lubricant on trombone slides. It’s also an ingredient in some moustache waxes. The artist Salvador Dalí claimed to use the same brand of moustache wax as Marcel Proust. In 2010, Dalí’s iconic, meticulously waxed moustache was voted the most famous moustache of all time.…

WHAT IS LIFE? BY ERWIN SCHRÖDINGER (£14.99, CAMBRIDGE UNIVERSITY PRESS) This laid the foundations of molecular biology, written by the physicist who co-founded quantum mechanics. I read it as a student and thought, “Yes, life is pretty weird!” GÖDEL, ESCHER, BACH: AN ETERNAL GOLDEN BRAID BY DOUGLAS HOFSTADTER (£19.99, BASIC BOOKS) This book addresses how wholes and parts can relate to each other in strange and counterintuitive ways. CONSCIOUSNESS EXPLAINED BY DANIEL DENNETT (£12.99, PENGUIN BOOKS LTD) A heroic attempt to explain – some might say explain away – the nature of consciousness. It’s written by a distinguished philosopher in a popular style. There’s much food for thought.…

WHAT RISKS COME WITH SMART GADGETS? The number one risk is invasion of privacy. If you’ve got smart cameras, or any device that’s listening to you, there’s a chance those can be hijacked and you can get spied on. We [my company, Pen Test Partners] found vulnerabilities in in-house security cameras, baby monitors and smart home assistants. We looked at an interactive kids’ doll that has a microphone and speaker, and connects to your phone via Bluetooth. When you connect to the doll there is no PIN, which means that anyone within Bluetooth range, 30, 40, 50 metres away, can connect. That means that someone outside on the street or in the next house can listen to the microphone and spy on your kids, and can talk to them as…

Make a chart of your life, divided into sections such as work, family, health and so on. Go over it regularly, considering whether anything needs attention in each area. If it does, mark that section until you have done it. Aim to keep the chart clear. By looking broadly at your life, you’ll be able to make sure that you’re not focusing on one area to the detriment of others. Read, watch or listen to something new every day. The unfamiliar subject matter will stimulate underused brain areas, making these brain cells easier to activate again in future, and helping to increase your overall attention. Take short breaks from tasks that need prolonged attention. When we’re doing the same thing for a long time, the brain interprets the continuous stimulus…

Challenge yourself with increasingly complicated problems. Eventually your brain will learn to abandon the fixed-attention strategy it uses for simple problems, and start to look at problems from multiple points of view. If you’re stuck on a puzzle, shift attention elsewhere and come back to it later. This turns off the neural firing pattern that is locking the brain into an unsuccessful approach, and allows the brain to incubate the problem, casting around unconsciously for knowledge that might be useful. When you return to the puzzle, this new information is likely to be incorporated into the problem-solving attempt. Combine problem-solving with a low-level activity such as walking or jogging. This helps to reduce focused attention because you need to use some of your conscious resources on the activity you’re performing.…

A varied diet should provide all the brain-healthy nutrients you need, but could you benefit from taking more of them? Omega-3 – the fatty acids found in fish such as herrings, sardines and mackerel – is the supplement best known as a brain-booster. But the evidence for its effects is underwhelming. A 2012 review by the Cochrane organisation – widely acknowledged as an authority on health research – found no evidence that omega-3 reduces the risk of cognitive impairment, while a 2015 meta-analysis by Canadian scientists concluded: “Omega-3 fatty acids, B vitamins, and vitamin E supplementation did not affect cognition in non-demented middle-aged and older adults.” Similarly, evidence for the herbal supplements ginseng and ginkgo biloba fails to stand up to scrutiny. The same goes for practically every other so-called…

Eye on the sky BEIJING, CHINA This isn’t a close-up of some newly discovered spider, but a bird’s-eye view of Beijing Daxing International Airport, currently under construction. The ‘eyes’ are skylights over the main hub of the terminal. The gates will be located along five spokes radiating from the centre, reducing the distance passengers have to walk: the maximum time to a gate should be eight minutes. When it opens in September 2019, its four runways will serve 72 million passengers annually. The subsequent opening of a further three runways will bring that number to over 100 million, making it the world's busiest airport. In comparison, London Heathrow served 80 million people in 2018. VISIT US FOR MORE AMAZING IMAGES: SCIENCEFOCUS BBCSCIENCEFOCUS Green screen CES,LAS VEGAS Nature and technology combine…

@StephenCWLL In an effort to stop getting behind on reading, I’ve made a cuppa and sat down for two straight hours to get through latest @sciencefocus magazine in record time. @Dolichon Nearly through Dry January and I haven’t noticed any improvement in health or well being. Does that mean I wasn’t drinking enough? It turns out that a lot of you have heard of James Clerk MaxwellÉ @sciencefocus James Clerk Maxwell: the most important physicist you probably haven’t heard of @Interesting_Ian Eh?? Never heard of? Would have thought most people would have heard of him. I haven’t heard of the majority of celebrities, but have certainly heard of Maxwell! @wfastronomer Born in India St in Edinburgh. The Physics and Astronomy Department building in Edinburgh is the James Clerk Maxwell Building,…

This is no yolk: scientists at the University of Edinburgh’s Roslin Institute have produced genetically modified hens whose eggs carry proteins that the human immune system uses to fight disease – the same proteins used to make types of drugs, including cancer medication. The research could pave the way for a cheaper means of mass-producing medicine. The technique does not harm the chickens. “This new approach is cheaper and more efficient” The researchers concentrated their efforts on two proteins: IFNalpha2a, which has powerful antiviral and anti-cancer effects; and macrophage-CSF, which is involved in the repair of damaged tissues. In both cases, once the eggs had been laid, the scientists could extract the proteins. “We are not yet producing medicines for people, but this study shows that chickens are commercially viable…

As the fireball of the Big Bang expanded and cooled, it went from white-hot to cherry-red before finally fading into invisibility. The Universe was plunged into blackness and the resulting cosmic dark age stretched on interminably. Over time, the Universe doubled in size, doubled once more, over and over again, then, one day, something extraordinary happened. The dark age came to an end. Across the entire length and breadth of the Universe, stars began switch on like lights on a Christmas tree. The first stars either came together under gravity to create the first galaxies, or were actually born in the clouds of gas and dust that made up the first galaxies. And the hunt to find these first galaxies is hotting up. One project – the Re-ionization Lensing Cluster…

I used to write articles like this one while sitting, slumped at my desk. Things changed at Christmas, when I was given a standing desk. My wife, Clare, decided my posture was terrible, and that although I intend to get up every 30 minutes and roam around, once I’ve sunk into my chair I rarely do. Many of us sit too much. We sit at work, in the car and at home, moving only to shift from one seat to another. Even if you exercise regularly, there is mounting evidence that it will not undo the damage done by prolonged sitting. So why is sitting so damaging? One thing it does is change the way our bodies process sugar. When you eat anything containing carbs, your body breaks it down…

The mind has a big role to play in how effective surgery is. One influential study, published in the prestigious British Medical Journal (BMJ), pulled together the results of more than 50 surgical trials that compared a widely used surgical technique, such cleaning out painful knee joints with salt water, with a placebo surgery. It showed that in 74 per cent of the studies, patients who just had the placebo surgery showed signs of improvement, such as reductions in pain. In fact, in 51 per cent of the trials, placebo surgery was as effective as the real thing. There are few who would doubt the importance of using placebo surgery to test out existing surgical techniques. But given that placebo surgeries do seem to work, isn’t there an argument for…

DR PAUL BARKER, BOURNEMOUTH WHEN I LOOK TO THE STARS, HOW FAR BACK AM I SEEING? All of the stars you can see with the unaided eye lie within about 4,000 light-years of us. So, at most, you are seeing stars as they appeared 4,000 years ago. All of these stars will die at some point, and astronomers have estimated that the death rate for visible stars in our Milky Way is around one star every 10,000 years. So given that we can only see 4,000 years back in time, it is unlikely (though not impossible) that any of them have died yet. In other words, choose any star in the night sky, and the chances are that you could visit it today (if you had a fast enough spaceship).…

It’s true. Last year, London Metropolitan University conducted swab tests on the self-order touchscreens in eight McDonald’s restaurants and found faecal bacteria on all of them. This isn’t because these restaurants are dirty: it’s because their customers are, and so are you. Every one of us has about 0.1 grams of poop trapped in our butt crack at any given time. This spreads to our clothes, then our hands and then to every surface we touch. You can clean the bathroom as much as you want, but bacteria are distributed as a fine mist every time you flush the toilet and will hang in the air for up to two hours, waiting to land on the next person to walk in. And your kitchen sponge, which you use to cleanthe…

WHAT I’M LISTENING TO Helen Glenny EDITORIAL ASSISTANT ASENSE OF TIME BBC RADIO 4, 3 APRIL I’d always thought of time as constant, but after talking to the BBC Radio 4 team about their upcoming show A Sense Of Time, I’m reconsidering. According to the Radio 4 team, we experience time at twice the speed of a leatherback turtle. Swifts and flies, on the other hand, process things even faster than we do, allowing them to dodge branches in a forest at speed or avoid a swatting hand. Swordfish have the process of manipulating time nailed: they can alter their sense of time by heating up or cooling down their brains. It sounds fantastic. Speed up time on a long cross-ocean commute, or slow it down when you’re…

Reality check AIR POLLUTION IN THE WORLD Real-time air quality index aqicn.org AIR POLLUTION IS KILLING US, HERE’S HOW YOU CAN STOP IT In this episode of the Science Focus podcast, pollution scientist Gary Fuller explains how bad our air is and how we can stop this invisible killer. bit.ly/stop_air_pollution THE FOUR-DAY WEEK Economist Lord Robert Skidelsky tells Helen Lewis about the four-day working week in this episode of BBC Sounds. bit.ly/four_day_working_week LOST IN A GOOD GAME BY PETE ETCHELLS (£13.64, ICON BOOKS) In this book, journey through the development of computer games, experience the highs and lows of gaming, and find out why it isn’t as antisocial as it may seem. Oldest galaxies in the Universe BIG BANG LADYBIRD EXPERT BOOK BY MARCUS CHOWN (£7.99, MICHAEL JOSEPH) This accessible…

Sometimes our brains just don’t want to play ball. Whether it’s an inability to concentrate, a tendency to forget where we left our keys, or a mental block on that final crossword clue, there are times when our minds seem to have – well – a mind of their own. Like any machine, our brains can sometimes benefit from a tune-up. Over the following 15 pages, we look at the latest thinking around six key areas of cognition, and provide some practical, science-backed tips on how to keep your mental cogs running smoothly.…

Consuming lots of B vitamins (found in whole grains, seeds, nuts and beans) may help. These aid many brain functions, including neurotransmitter production. One study found that high doses of B vitamins halved the rate of brain shrinkage in people with mild memory problems. But the jury is still out on vitamin B (see p15). Use mnemonics such as rhymes (‘30 days has September’) and acronyms (‘Richard Of York Gave Battle In Vain’) – both tried-and-tested ways of making information more memorable. Construct a mental picture of a familiar location, such as your home, and place things that you want to recall in its rooms so that you can mentally stroll through the image and spot the unfamiliar items you’ve stored there – a bit like Sherlock’s ‘mind palace’. Write…

BRAIN ZAPPERS Strapping electrodes to your skull to stimulate your brain with a buzz of electricity might sound scary, but done properly, non-invasive ‘transcranial direct-current stimulation’ (tDCS) is safe – it uses a minute charge and feels tingly but not painful. tDCS is extremely well-researched – it features in more than 2,000 studies published in mainstream academic literature – and has been found safe and tolerable, even for children. So would you benefit from tDCS? Many studies have found that it improves a wide variety of cognitive skills, and helps relieve mood disorders such as depression, but there are some studies that show minimal or no benefit. Generally, around 10 to 20 minutes of tDCS a day seems to have modest, cumulative effects. Most studies have been conducted on people…