Sommaire pour August 2020 de BBC Science Focus Magazine

Ride and dine At the risk of sounding at best a bit weird and at worst completely barking, I have always been fascinated by cheese, ever since I was forced to watch White Christmas as a child and Bing Crosby explained how different cheeses can affect your dreams. I have, in the past, eaten particularly pungent cheeses at bedtime in the hope of dreaming the winning lottery numbers. In your July issue (p66), Dr Farrimond explained why some people like strong cheeses and why we have a ‘taste’ for danger foods. This idea linked to the dopamines mentioned in the piece on rollercoasters in that same issue (p70). Perhaps I could launch a gourmet thrill experience in partnership with a theme park. Puffer fish (illegal in the UK), then a…

Venus is home to at least 37 recently active volcanic structures, a study by researchers at the University of Maryland and the Institute of Geophysics at ETH Zurich has found. This is the first evidence that the interior of the planet is still geologically active. Previous studies have discovered evidence of a warm interior and ring-like structures known as coronae. Coronae form when plumes of hot material deep inside the planet rise through the mantle layer and crust, in a manner similar to the way that mantle plumes formed the volcanic Hawaiian Islands. It was originally thought that they were signs of ancient activity, and that the planet had cooled enough to slow down the geological activity in the planet’s interior, hardening the crust so much that any warm material…

Astrophysicists have suggested that the hypothetical Planet Nine could be a tiny black hole, and they’ve proposed a way to find out if this is really the case. “We do not know exactly where to look for Planet Nine” Planet Nine has never been seen directly, but the existence of a ninth planet orbiting our Sun could explain certain features of the outer Solar System, such as the clustering together of icy rocks called ‘trans-Neptunian objects’ with similarly tilted orbits. Last year, scientists in the UK and US suggested that Planet Nine could instead be a primordial black hole. These as-yet-unseen black holes are thought to have formed a fraction of a second after the Big Bang. If Planet Nine was such an entity, it would be about the size…

WHAT DID THEY DO? Researchers at UCL and Newcastle University trained monkeys to pull a weighted handle using one arm, and gradually increased the weight over 12 weeks. Each day, they stimulated the monkeys’ motor cortices (the motor cortex is the part of the brain that is involved in movement) and measured the electrical activity in their arm muscles. WHY DID THEY DO THAT? The brain controls movements using two major neural highways connected to the spinal cord: the corticospinal tract (CST) and reticulospinal tract (RST). When people start working out, they initially get stronger by increasing connections in the nervous system, not by growing bigger muscles, but the details of which connections change were unknown. WHAT DID THEY FIND? The more the monkeys trained, the more the electrical response…

Between 2000 and 2017, levels of the potent greenhouse gas methane barrelled up toward pathways that climate models suggest will lead to between 3°C and 4°C of warming before the end of this century, researchers at Stanford University have found. Increases are being driven primarily by the growth of emissions from coal mining, oil and natural gas production, cattle and sheep ranching, and landfills, which could lead to an increase in natural disasters, including wildfires, droughts and floods. Methane is a colourless, odourless gas that is 28 times more powerful than carbon dioxide at trapping heat over a 100-year period. In 2017, the Earth’s atmosphere absorbed nearly 600 million tons of methane, a 9 per cent rise since the early 2000s, with more than half of all emissions coming from…

In February this year, the Solar Orbiter craft was launched aboard an Atlas V rocket from Cape Canaveral, Florida. With six remote-sensing telescopes and four in-situ instruments, the probe is on a mission to image and monitor the Sun and its surrounding environment. Led by the European Space Agency (ESA) and aided by NASA, the project soon encountered a number of challenges due to the coronavirus pandemic. However, in mid-June the team announced that the probe was ready to start performing science, and it’s already delivering the goods. In mid-July, ESA released this set of images from a distance of 77 million kilometres from the Sun - the closestever photographs of our star. The probe is now in its cruise phase and will continue travelling towards the Sun. In late…

Statues and sculptures have always been used to convey information and ideas. They have formed a part of our cultural sensibilities and urban design for as long as we remember, but there are always periods in history when these become more prominent than others. Public memorials are erected to mark regeneration and rejuvenation of a city or a country, and to celebrate heroes who we believe have been instrumental in shaping our collective national identity. The foundation for a unique nationalistic identity, and crucial to people’s sense of belonging, is collective memory. The notion of collective memory was first postulated by French philosopher Maurice Halbwachs. Halbwachs asserted that it is in society that we acquire most of our memories, that there exists a collective memory, and “it is to the…

The Earth is in trouble. Dying crops and deadly dust storms are putting the planet under strain, leaving the human race in grave need of a new home. In a desperate attempt to find one, a team of brave astronauts led by Joseph Cooper venture into a wormhole near Saturn, emerging light-years away on Miller’s planet - an ocean world orbiting a supermassive black hole known as Gargantua. So goes the plot of the 2014 Hollywood epic Interstellar. But according to recent research, this idea might not be as far-fetched as it first appears. The ability to spot other planets in space has made staggering progress in the last quarter of a century. We now know of more than 4,000 exoplanets - worlds beyond our Solar System orbiting distant stars.…

THE LOCKDOWN HAS MEANT MY STEP COUNT HAS DROPPED FROM 10,000 TO 7,000. SHOULD I BE WORRIED? There’s no denying that walking is good for your health, but there’s nothing magic about the number 10, 000. This figure is thought to have come from a Japanese pedometer called ‘manpo-kei’ (literally ‘10, 000 steps meter’), marketed as a device for the health-conscious in the run-up to the 1964 Tokyo Olympics. The 10, 000 steps target has probably stuck around because it’s easy to measure and easy to remember. But a 2019 study led by researchers at the Harvard Medical School measured the step counts of almost 17, 000 women over four years and found that the benefits tapered off well before 10,000 steps. The least active women averaged about 2, 700…

Hubble bubble HUBBLE SPACE TELESCOPE This brightly coloured, glowing bubble of gas and dust is the planetary nebula, NGC 7027. It measures just 0.2 by 0.1 light-years in size, and is one of the smallest and brightest planetary nebulae. It is located some 3,000 light-years away in the Cygnus constellation. Planetary nebulae are formed when ageing stars shed their outer layers of gas into space. New images from the Hubble Space Telescope will allow researchers to study NGC 7027 in the near-ultraviolet wavelength for the first time, which may help unlock some of the mysteries of this object. One theory is that a closely orbiting binary star has been sloughing off material for thousands of years, seen here as blue rings, but now the nebula has entered a more violent…

Dinosaurs and flying pterosaurs are some of the largest animals that ever lived, but a newly described fossil from Madagascar suggests that their ancestors were surprisingly small. The fossilised reptile, which lived around 237 million years ago, has been named Kongonaphon kely, or ‘tiny bug slayer’ (derived from both Ancient Greek and the Malagasy language of Madagascar). The creature stood only 10 centimetres tall - about the size of a coffee cup. K. kely dates from the time in the Triassic when the dinosaurs and pterosaurs, which both belong to a group called ‘Ornithodira’, branched into separate evolutionary paths. “There’s a general perception of dinosaurs as being giants,” said Dr Christian Kammerer, a palaeontology curator at the North Carolina Museum of Natural Sciences, who took part in the research. “But…

The natural ability of some maize plants to resist insect attack could be harnessed as a biological pesticide, according to new research led by Keele University. Pests can cause devastating losses to crops, but some maize plants will send out a chemical signal when a ‘stemborer’ moth has laid its eggs on the plant, in order to recruit parasitic wasps that lay their eggs in the moth caterpillars. To find out more about the genetics behind the defence mechanism, Keele University’s Prof Toby Bruce, in collaboration with the International Centre of Insect Physiology and Ecology, and the International Crops Research Institute for the Semi-Arid Tropics in Kenya, investigated the genetics of 146 types of maize plants. The plants included traditional varieties of maize (known as ‘landraces’), as well as inbred…

You might be able to apply black make-up, dye your hair a dusky tone and drape yourself in black leather, but you’ll never be as goth as some species of deep-sea fish. A team of scientists from Duke University and the Smithsonian National Museum of Natural History have found that the skin of some deep-sea fish absorbs more than 99.95 per cent of the light that hits them, making them appear ultra-black. In the dark environment in which they live, where even a tiny bit of reflected light can attract unwanted attention, this intense black colour improves their chances of survival. Duke University’s Dr Karen Osborn, who co-led the research, first discovered the incredible properties of the fish when she tried to photograph some of the specimens that she’d brought…

The oceans are the biggest, wildest, least understood part of the planet. But we’re getting to know them better every day, thanks to a host of technologies that are fathoming the depths in new and inventive ways. Some researchers are capturing things from the sea and transporting them into the lab to study in detail; others are rigging the oceans with novel sensors and devices, or probing them with algorithms. Together, these approaches are offering brand new views of the underwater world, at a time when it’s never been more important to decipher the inner workings of the oceans. From coral reefs to deep-dwelling jellies, the oceans’ living inhabitants face greater threats from human activities than ever before. The seas are polluted and overfished, marine habitats are being destroyed, and…

HOW CAN I SPOT THE INTERNATIONAL SPACE STATION? WHEN: ALL YEAR ROUND At any given moment, there are up to six humans orbiting 400km above our heads in a huge science laboratory. The International Space Station (ISS) is the Earth’s biggest artificial satellite, and it’s also a very good reflector of sunlight, making it the brightest object in our sky after the Sun and the Moon. Spotting the ISS with the naked eye is one of the most fun and rewarding stargazing activities - you just need to know when and where to look. The ISS is travelling at a speed of around 28,000km/h (planes, by comparison, fly at around 900km/h), so it whizzes around the Earth once every 90 minutes, and crosses the sky in six minutes or less.…

HOW DOES EVOLUTION WORK? HOW DO WE KNOW THAT HUMANS EVOLVED FROM APES? The evolutionary changes we see occurring over a few decades are modest: a cricket that evolves to be silent is still a cricket. When evolution unfolds over longer timescales – thousands or millions of years – it can lead to much larger changes in physical appearance. This is why a microbe that lived billions of years ago ultimately evolved into every species alive today. By carefully assessing physical and genetic similarities, evolutionary biologists can work out which species belong in the same area of the family tree of life. Doing so suggests that humans are more closely related to chimpanzees than to any other species alive today, implying that we both evolved from the same ‘parent’ species,…

Cheesed off I note with amusement you have been talking about cheese and how brains love it (July, p66). How about those of us that cannot stand the stuff? What are we missing? To me, it is disgusting in any form, no exceptions-like eating something gone bad! Thomas Stanley What’s up with that? In April’s What Hubble Taught Us (p51), it said that astronomers are questioning why the Universe is still expanding, when it should be slowing down or at a plateau. “We still don’t really understand, ” quotes Jennifer Wiseman. Surely, unless I’m missing something, the Universe simply hasn’t reached that point. By what calculation has science deemed that we’ve reached the plateau? Murray Cornwell, Florida It’s not surprising that the Universe is still expanding, as you said. We would…

A marine bacterium has been genetically engineered to produce spider silk, which has many applications in the medical, aerospace and clothing industries. The silk that spiders use to form the spokes of their web is called dragline silk, and it’s tough, lightweight and biodegradable. It’s also biocompatible, which means it works well with living tissue and is not attacked by an animal’s immune system, making it a sought-after material. It can be used for applications such as durable materials, drug-delivery systems, implant devices, and scaffolds for tissue engineering. One spider can only produce trace amounts of spider silk, and because the arachnids are territorial and often cannibalistic, it’s not possible to breed large groups for this purpose. Teams around the world have therefore tried to find a way to generate…

As well as spending time with their close relatives, beluga whales also frequently associate with individuals they have no relation to, a study at Florida Atlantic University’s Harbor Branch Oceanographic Institute has found. Belugas make friends with others outside of their family groups, and beluga communities have similarities to human societies where social networks, support structures, cooperation and cultures involve interactions between kin and non-kin. The study brought together decades of research using molecular genetic techniques and field studies spanning 10 locations across the Arctic from Alaska to Canada and Russia to Norway. The team found that belugas form several different group types, each with associated behaviours that were consistently observed across different populations and habitats. “Unlike killer and pilot whales, and like some human societies, beluga whales don’t solely…

Back in January, when the coronavirus was very new and still confined to Wuhan, we were working on the assumption that COVID-19 was more or less an ordinary respiratory disease. The World Health Organization described the symptoms as “mainly fever, with a few cases having difficulty in breathing”, with some patients developing pneumonia. Even on 31 January when the UK’s first cases were confirmed, Prof Chris Whitty, the chief medical officer for England, described COVID-19 as a “relatively minor disease” for most people, going on to say that those who were most seriously affected would be treated “as anyone else with a respiratory disease”. As time went on, however, more and more symptoms were added to the list. “People have a very large number of different symptoms and many of…

FAIRWEATHER FRIENDS ST HELENA, SOUTH ATLANTIC OCEAN Every day at 11:15am, a team of meteorologists on the Atlantic island of St Helena release a giant latex weather balloon into the sky (previous page). They wear goggles, flash hoods and overcoats ‘just in case’, because the balloons are full of highly-explosive hydrogen (this lighterthan-air gas causes the balloon to ascend). As the balloon rises to a height of more than 30km, a mini weather station or ‘radiosonde’ attached to the balloon’s neck sends back second-by-second information on temperature, humidity, wind speed and pressure. St Helena’s meteorological station (part of which is seen in the image below, being tended by the station’s technical manager Marcos Henry) is one of 190 such stations worldwide monitoring the Earth’s upper atmosphere as part of the…

THE RED-LIPPED BATFISH The red-lipped batfish flaunts its outrageous scarlet pout with all the charisma of a 1980s goth frontman. No one knows exactly why the batfish sports its signature look, but it may help it to attract mates, or to recognise others of the same species at spawning (reproduction) sites. The red-lipped batfish lives at depths of up to 75 metres in the waters surrounding the Galapagos Islands, where it is adapted to life as a bottom dweller, living and feeding on the seafloor. It is a poor swimmer, but modified fins act as makeshift legs, helping it to ‘walk’ along the sand. Well, it’s more of a froggy waddle, but when a little more speed is required, the batfish can push off with the ‘pelvic’ fins beneath its…

A CROSS 1 A crab managed with one tongue (6) 5 We sat around - hard work (5) 9 Model is quiet at rent review (7) 10 Record vagrant going behind a lake (5) 11 Notes played together in Circle Line (5) 12 Used real tin out of military convenience (7) 13 Bishop acquires modest affliction (6) 15 Muscle radiating around the white bit (6) 18 Laugh, wrapping a pram around a jug (7) 20 Time going from left to right for a drink (5) 23 Bowl - graduate’s batting (5) 24 Lie - ours turned out stringy (7) 25 Returning, say, see off some birds (5) 26 The cricket team’s legs (6) DOWN 2 More trouble, old-fashioned at heart (5) 3 The bard worked in one dimension (7) 4…