This week’s Red Folder opens with a fantastic video (above) from the folks at Veritasium. It involves dropping a spinning basketball from the top of a very tall dam in Tasmania and watching as the ball accelerates away from the face of the dam before bouncing across the surface of the water below. In comparison, a non-spinning ball simply falls straight down. This happens because of the Magnus effect, which has also been used to create flying machines and sail-free wind-powered boats. The effect also plays an important role in ball sports such as tennis and is explained in much more detail in our article “The physics of football”.
Alien hunters: Yuri Milner (left) and friends announce the Breakthrough Initiatives. (Courtesy: Breakthrough Initiatives)
By Hamish Johnston
Earlier this week in London the billionaire physics enthusiast Yuri Milner joined forces with some of the biggest names in astronomy and astrophysics to announce a $100m initiative to search for signs of intelligent life on planets other than Earth. The money will be used to buy time on a number of telescopes to search for radio and optical signals created by alien civilizations.
Mechanics was never my favourite topic when I was studying physics for my BSc, but I think I might have been more interested if we had looked at real-world situations rather than square blocks sliding down an incline plane. A bicycle that carries on, sans rider, without toppling over for quite a long time, for example, would have got my attention. This is a rather well-known quirk of mechanics though and it isn’t even the first time we have discussed it on the blog. Indeed, Physics World‘s James Dacey, a keen cyclist, delved into the topic in 2011. This week, we spotted a a new Minute Physics video on the subject, over at ZapperZ’s Physics and Physicists blog. Watch the video to get a good, if a tiny bit rushed, explanation of the three forces that come into play to allow a bicycle at a certain speed to zip along without its human companion. As the video suggests, all is not known about the secrets of free-wheeling bicycles just yet though, and I have a feeling that we will blog about it again in the years to come.
Are countries such as the UK, the US and Canada suffering from a shortage of scientists and engineers, or are scientists and engineers struggling to find jobs there? Our US correspondent Peter Gwynne reports that, according to a recent survey, physicists in that country can expect to be rewarded with handsome salaries if they work in industry – which suggests that their skills are in great demand. However, over in the New York Review of Books, an article on “The frenzy about high-tech talent” claims that “by 2022 the [US] economy will have 22,700 non-academic openings for physicists. Yet during the preceding decade 49,700 people will have graduated with physics degrees.”
In the past few years, Physics World has publishedseveralarticles on the “STEM shortage paradox”, where reports of severe skills shortages in science, technology, engineering and mathematics (STEM) coexist with lukewarm – and sometimes borderline alarming – data on employment in these fields. Hence, conflicting reports on career prospects for physicists don’t really surprise us anymore (although this is actually slightly different to what we’ve seen before, in that rosy employment data are going up against a downbeat statement about demand, rather than vice versa). But even so, when two reports point in such different directions, it’s tempting to conclude that one of them must be wrong, or at least missing something important.
The Solarquest board, complete with planets, moons and artificial satellites.
By Margaret Harris
Last night, in honour of the New Horizons mission to Pluto, I pulled out my copy of Solarquest. This classic board game was a childhood favourite of mine, and it’s basically Monopoly in space: instead of buying properties named after streets in Atlantic City, New Jersey (or London, if you’re British), you buy planets, moons and artificial satellites. Then, when your fellow players land on an object you own, you charge them rent.
Such nostalgia is all well and good, I hear you say, but what’s it got to do with New Horizons or Pluto? Well, Solarquest’s inventors clearly took their science seriously. By board game standards, there’s quite a lot of physics in it. For example, you can’t leave a planet unless you roll a number high enough to overcome its gravitational pull, and its Monopoly-like property deed cards include facts about each planet and moon as well as their prices.
Perfect view: the sharpest image of Pluto to date taken by the New Horizons spacecraft. (Courtesy: NASA)
By Tushna Commissariat
After trundling through our solar system for more than 10 years, NASA’s New Horizons mission made its closest approach to the dwarf planet Pluto earlier today, at 12:49 BST. It was a mere 12,472 km from the planet’s surface – roughly the same distance from New York to Mumbai, India – making it the first-ever space mission to explore a world so far from Earth.
If you want to find out more about the New Horizons mission, read this recent news story by physicsworld.com editor Hamish Johnston. Above is best close-up view of this cold, unexplored world that the spacecraft sent back before its closest approach (when it was still 766,000 km from the surface), revealing in clear detail many of the planet’s surface features, including the “heart” at the bottom.
Here’s a Tuesday quiz for you. If you disagree with a colleague about something scientific, what should you do? Your choices are:
(a) Nothing. This is science, and the truth will win out no matter what I do;
(b) Take them aside and explain, privately, why you think they are wrong. Then, if they still disagree with you, get even by writing snarky anonymous reviews of their papers;
(c) Organize a panel “discussion” and tear them to shreds in front of all your colleagues;
(d) Take your case to the public by writing a popular-science book explaining the superiority of your own theory.
Okay, this is a trick question: I’m not sure any of those options is really a good idea (although I’m sure they’ve all been tried). I’d like to focus on the last one, though, because it was the subject of an interesting talk at the Science in Public conference, held last week in Physics World’s home city of Bristol.
At the end of next week millions of children in England and Wales will start their summer holidays and many parents will now be scrambling to find activities to keep their little dears occupied. Physics World can recommend a virtual trip to ILC Science Kids Club courtesy of the Tokyo Cable Network and Japan’s Advanced Accelerator Association. ILC stands for International Linear Collider, which is one of several proposed to take over when the Large Hadron Collider is eventually retired. In the first video of the series, a boy called Haru learns why scientists are keen on building accelerators from his Uncle Tomo. The video is in Japanese with English subtitles, so as well as learning about particle physics, your little tykes might even pick up a little Japanese.
When you think of cutting-edge experimental physics, you might picture the grandiose detectors of the Large Hadron Collider (LHC), or perhaps a lab-coat-wearing scientist hunched over a shiny new microscope. Sometimes, however, all you need is a bucket of sand, a balloon and a pin.
Spinning around: The air flow from the wing of a plane, made visible by using coloured smoke. (Courtesy: NASA)
By Ian Randall
If you’re as impatient as I am, the worst part about flying off for your summer vacation is the interminable hold-up that sometimes occurs right before take-off – waiting for the plane to taxi onto the runway and desperately hoping the in-flight entertainment will kick off soon. But these annoying delays may soon be cut down thanks to Georgios Vatistas and colleagues at Concordia University in Montreal. The team has developed a new mathematical airflow model to help refine the safe separation distances needed between planes during take-off and landing.
As an aeroplane moves along, the lift-generating difference in pressure between the top and bottom surfaces of its wings causes air to flow out from beneath each wing and up around the wing tip. This creates a circular vortex pattern behind each tip (pictured above), with a downwash in-between – forming a turbulent wake that can be hazardous to any craft that passes through it. If large enough, this turbulence can roll the next aircraft, faster than they can resist – leading to a crash.