Table of contents for Issue 187 in How It Works

Whether or not we’re actively thinking about it, time permeates every aspect of our lives, big or small, just the same way it did thousands of years ago. Back then, ancient civilisations were trying to accurately measure the length of a day and track the movement of the planets in space. Egyptians invented a simple but effective water clock, while a Greek mathematician is thought to have constructed the first analogue computer, which could predict the next eclipse, among other important timings. Today we have insanely accurate atomic clocks that allow scientists to make precision observations that were impossible just a decade or two ago. You can read more about our understanding of time, starting on page 26. Enjoy the issue! SUBSCRIBE NOW WHAT WE’RE ANTICIPATING FOR EXCLUSIVE HIW NEWS…

Time is something we all take for granted, yet it can be very difficult to grasp when we think hard about it. As long ago as 400 CE, Saint Augustine remarked that he knew exactly what time was, except when he tried to explain it. Many of us might say the same thing today, and the world’s philosophers are still arguing with about the exact nature of time and how we perceive it. Fortunately, there are some aspects of the subject that we’re now able to pin down much more precisely, thanks to super-accurate timepieces and sophisticated mathematical theories. The next few pages are a guided tour of some of the most fascinating highlights. We’ll start by looking at the way our measurement of time has evolved over the centuries,…

Today you can virtually visit almost any street or landmark in the world, viewing an accurately mapped layout of its placement on the planet. When navigating new roads, real-time updates about weather and traffic conditions can keep us constantly in the know. This combines satellite and street-level imagery, incorporating huge amounts of data quickly and accurately. But before computers and satellites could lend a hand, the work of cartographers and surveyors was far more laborious and less accurate. Maps have long been an essential tool for human civilisation, helping our ancestors piece together the world around them, document borders and navigate new landscapes. The first maps of 600 BCE were carved into chunky clay tablets. As human understanding of the world grew beyond local territories, maps escalated from local representations…

Stem cells are the ‘parent’ cells from which all other cells in our bodies arise. They are nature’s building blocks, with the potential to become any type of cell – from the skin on the soles of our feet to photoreceptors in our eyes. While scientists suggested their existence as far back as 1908, it wasn’t until 1978 that they were finally discovered in umbilical cord blood. Stem cells quickly became the focus of a scientific and media frenzy. There was much speculation about their potential to solve all sorts of medical issues – from curing diseases such as Alzheimer’s to creating whole new organs – thanks to their ability to change into any cell type and therefore replace those that have been damaged or lost. But this excitement was…

Between 10 and 25 miles above our heads in the stratosphere, there is a layer of oxygen dedicated to blocking dangerous forms of solar radiation, called the ozone layer. Along with visible light, the Sun also emits rays of radiation in the form of ultraviolet (UV) light. Within UV are three different wavelengths of light, commonly referred to as UVA, UVB and UVC, each of which has different levels of energy. UVA is the least energetic light, while UVB sits in the middle and UVC is the most energetic. On their journey from the Sun and into Earth’s atmosphere, the high energy of the UVC rays is absorbed by the oxygen molecules that form the ozone layer. The lower energy wavelengths of UVA and UVB, however, can pass through ozone…

Many sports in which you throw, aim or knock down objects also require you to collect the items and reset the playing zone. But anyone who has tried their hand at indoor bowling will have seen the mechanical efficiency in which a strike is cleaned up and the lane reset. A sophisticated robotic system cycles the pins and sets them up with precision for another game. Bowling dates back over 5,000 years to the ancient Egyptians, who used stones as balls and various materials for pins. Since then, the game has evolved drastically. Before this machinery was perfected, the role of pinsetter was held by a person who stood just beyond the firing line at the back of each lane. The mechanical pinsetter that replaced this job was invented in…

AROUND THE WORLD IN 80 INVENTIONS A BOOK WITH A BIT EXTRA AUTHOR MATT RALPHS ILLUSTRATOR ROBBIE CATHRO PUBLISHER TEMPLAR PUBLISHING PRICE £16.99 / $21.65 RELEASE OUT NOW What do we mean by a bit extra? This is another title in the popular series that follows Around the World in 80 Instruments and Around the World in 80 Trees – both of which we’ve already reviewed in previous issues of How It Works. So if you’ve read either of those, you’ll understand the premise of Around the World in 80 Inventions, which is the science, tech and history behind 80 inventions from around the world – nominally, at least. Among the half and single-page entries such as the internal combustion engine, chocolate and kevlar body armour, author Matt Ralphs has…

In 2010, hundreds of people gathered at a dock in Kiel, Germany, to witness the unveiling of the MS Tûranor PlanetSolar, a solar-powered catamaran that was set to be the first of its kind to circumnavigate the globe. It took one year, seven months and seven days for Tûranor PlanetSolar to cross more than 37,296 miles to circumnavigate the globe, docking in six continents along the way and setting the record for the longest journey made by a solar-powered boat. In place of a traditional fossil-fuelled engine, this catamaran runs solely on the power of the Sun. Spread across the entire upper portion of the vessel is an array of photovoltaic cells covering 512 square metres. These power cells convert sunlight into electrical energy to charge over eight tonnes of…

During the last ice age, humans ventured into two vast and unknown continents: North and South America. For nearly a century, researchers thought they knew how this wild journey occurred. The first people to cross the Bering Land Bridge, a massive swath of land that connected Asia with North America when sea levels were lower, were the Clovis, who made the journey shortly before 13,000 years ago. According to the Clovis First theory, every Indigenous person in the Americas could be traced to this single inland migration. But in recent decades, several discoveries have revealed that humans first reached the so-called New World thousands of years before we initially thought, and probably didn’t get there by an inland route. Who were the first Americans, and how and when did they…

Scientists have taken the next big stride in nuclear fusion technology with the switch-on of the Japanese Torus-60 Super Advanced (JT-60SA), the current record holder for the world’s largest tokamak. Situated at Japan’s National Institutes for Quantum Science and Technology (QST), the tokomak has produced plasma volumes up to 135-cubic-metres and has been created in a collaboration between the European Union’s Fusion for Energy and QST. The word ‘tokamak’ comes from the Russian acronym for ‘toroidal chambers with magnetic coils’, and like others of its kind, JT-60SA generates energy by harnessing the power of nuclear fusion reactions. To achieve this, a fuel of superheated deuterium and hydrogen is injected into the doughnut-shaped vacuum chamber at the core of the machine, which is controlled by coils of superconducting magnets. A powerful…

Keratin is a protein that adds strength to many of your body’s hard and soft external tissues. It is predominantly found in the hair, nails and outer layer of skin, but is also in many other glands and organs. The molecule is much tougher than others in the body, being more resistant to tearing and scratching. Keratin is also waterproof and isn’t dissolved by acids, alkalis or most of the body’s natural chemicals. Your body produces keratin itself, but relies on you consuming enough protein as part of your diet. If you aren’t eating enough, your body struggles to make an adequate supply of keratin and you might experience brittle nails, thinning hair and dry or flaking skin. Keratin keeps your many millions of skin cells connected and working together…

In seawater worldwide, microscopic organisms called plankton are bobbing along with the current. Plankton are vital for maintaining balance, not only in marine ecosystems, but also in regulating the global climate. Plankton can be divided into two different categories: phytoplankton and zooplankton. Phytoplankton, also known as microalgae, are chlorophyll-packed organisms that operate in the ocean in a similar way to how plants live on land. To obtain their food and energy, phytoplankton perform photosynthesis. These tiny invertebrates convert sunlight and carbon dioxide dissolved in the water into energy, releasing oxygen as a byproduct. Their requirement for sunlight means that plumes of phytoplankton are found drifting near the surface, moving around the world at the mercy of ocean currents. Zooplankton, on the other hand, are microscopic organisms made up of many…

Why doesn’t NASA take parts into Earth orbit and build a spaceship to go to Mars up there, like the ISS? There are a few reasons why we haven’t sent a manned flight to a planet like Mars yet. The distance is one. At their closest Mars and Earth are still 50 million miles away, or about seven months travel time. They’ll need supplies on board for all that time. Even if advances in rocketry can reduce the time, once on Mars astronauts will have to wait up to a year and a half to return, when the orbits of the planets align just so. A spaceship big enough to contain all the necessary supplies would be too big to launch from Earth’s gravity given our current technology, so we…

The internal components of a modern car can be tricky to pinpoint at the best of times – and once they’ve been subjected to a high-speed impact, the task becomes even more difficult. That’s a problem if you’re a crash researcher who wants to examine the wreck to find out how each element has fared. There’s a risk of compromising the evidence as you pick apart the wreckage. If only there was a giant version of the kind of X-ray scanners we use to look at bones, it would be possible to get a detailed look inside the vehicle without disturbing it. The Fraunhoffer Society in Germany has such a scanner – one so big it can accommodate cars, aeroplane wings and dodgy shipping containers. This giant scanner enables users…

Every three months or so, Earth shifts from one of its four seasons into the next. This can mean a shift from summer sunshine to a colder autumn. But wherever you are in the Solar System, the seasons change in line with the planet’s movement around the Sun. As Earth zips along its 365-day solar orbit, it also spins on a fixed axis which is slightly tilted, at 23.5 degrees. Known as its obliquity, a planet’s degree of tilt determines the exposure of sunlight that reaches each of its hemispheres as it orbits the Sun. It’s measured using the planet’s axis, which runs through its poles, and an imaginary vertical line that runs through it perpendicular to the Sun’s equator, referred to as the orbital plane. When a planet is…

If you stand in front of a mirror and open your mouth wide, at the back of your throat you should be able to see two pink lumps of tissue poking out from the flesh at the sides. These are your tonsils, which are vital tools of the immune system. Tonsils work to defend the body from infection by trapping, detecting and fighting bacteria, viruses and other harmful intruders. The trapping of these infection-causing cells is assisted by the structure of the organs, as they are covered in crevices called crypts. When bacteria and viruses enter the mouth or nose, they are likely to come into contact with the tonsils. Immune cells called lymphocytes are activated in the tonsils, launching an attack before an infection can take hold. When the…

Around 40 lives are lost in the Australian Outback every year. It’s a land that only some of the most resilient of Earth’s plants and animals are capable of calling home. Aboriginal tribes have mastered survival in the Outback over the course of 65,000 years, learning to live in the unique environment and source meals from sparse and poisonous vegetation. Most tribes respect the power of nature in the Outback to give and take life, and have become wiser through each generation. Their innovative methods that utilise the resources around them include extracting parts of plants as medication for illness and animal-inflicted injuries. For example, the leaves of the emu bush are used to wash cuts, and have demonstrated similar natural strength to modern antibiotic medication. Meanwhile, the bright-orange desert…

For around 12,000 years, humans have been deliberately sowing seeds to grow plants for our species to benefit from. It’s a practice that enables communities to settle in one place and claim a patch of land as their home. Stone, bone and wood were first crafted to make digging and raking tools for agricultural purposes, and the essential pieces of equipment that most gardeners use today haven’t changed much. However, the use of stronger materials, like steel for blades, and today’s electric appliances have changed the gardening game. The average European gardener uses three powered gardening tools. As modern technology advances, more efficient garden tools reduce the time and effort required by gardeners to carry out simple gardening tasks. For example, before lawn mowers were invented in 1830, individuals would…

Many have grappled with this question since the 1930s, when it became widely accepted that black holes might exist. Einstein’s theory of general relativity tells us that all mass deforms space and time, causing paths taken by particles to bend towards the mass. At the event horizon of a black hole – the boundary in space-time through which matter and light cannot escape once crossed – the deformation of space and time is so strong, there are simply no paths that lead away from the black hole. Once matter or light has crossed the event horizon, it becomes impossible to determine what happens to it afterwards, since information from that event can never reach an outside observer. IF YOU JUMP UP ON A MOVING PLANE, WHY DON’T YOU LAND FARTHER…