The physics of football
No-one forgets a great goal in football. As players from 32 countries prepare for the 1998 World Cup in France, find out how top footballers strike the ball to maximum effect
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Read article: The physics of football
Challenges in the nanoworld
Sometime early in the next century the miniaturization of conventional electronic devices will grind to a halt. The inexorable progress that has seen the number of transistors on a single silicon chip increase by a factor of 16 000 over the past 24 years cannot continue indefinitely. A combination of reasons – cost, technology and […]
Fibre gives X-ray generation a boost
The efficiency with which light of one frequency is converted into a higher frequency in a nonlinear material increases when both frequencies travel through the material with the same phase velocity. This condition is known as phase matching. This technique is traditionally used in solids, but few solids are transparent at extreme ultraviolet and soft […]
Has Hubble photographed an extrasolar planet?
Terebey and colleagues believe that the new planet was in orbit around two stars – TMR-1A and -1B – before it was ejected by a gravitational slingshot mechanism. The planet then created a “light tube” as it burrowed through the dust clouds surrounding the binary star system. It was this light tube that attracted attention […]
First light for Europe’s new telescope
The VLT uses active optics to reduce the effect of atmospheric turbulence on observations. In this technique the optical quality of a star is continually monitored against a reference star and the surface of the mirror adjusted to ensure that the image remains focused at all times. Similar adjustments are made to counteract the effects […]
Isotope production comes back on-line in Canada and the US
Brookhaven will produce germanium-68, which is used to calibrate positron emission tomography (PET) scanners, and copper-67 for diagnostic and research purposes. It will also make strontium-82: this isotope decays into rubidium-82, which is widely used in studies of the heart. The recently upgraded Brookhaven Linac Isotope Producer (BLIP) accelerator will be used to produce the […]
Pakistan retaliates with nuclear tests
Sharif claimed on national television that the country had exploded five nuclear devices. Presently only two explosions -with 12 and 25 kiloton yields – have been confirmed by seismic monitoring stations. The other three tests are suspected to have been subkiloton devices. “Had India been penalised for its actions we would not have conducted these […]
World supply of medical isotopes under threat
The Chalk River lab is owned by Atomic Energy of Canada (AECL) and supplies molybdenum-99, iodine-125, iodine-131 and xenon-133 to MDS Nordion for the manufacture of radiopharmaceuticals. A derivative of molybdenum-99 – technetium 99 – is used in 90 per cent of hospital radiopharmaceutical medical procedures. This amounts to over 15 million medical procedures per […]
Salty oceans on Europa
Europa is roughly the size of the Moon and is 85% water by weight. An icy crust reflects most of the light falling on the satellite. In 1979, the Voyager spacecraft flew past Europa and discovered a series of cracks and glacier ripples (see picture) on the surface. This led astronomers to believe liquid water […]
Small in size, high on impact
Secrets of success One of the reasons for this high impact is that Scandinavian physicists specialize in niche areas. According to Ole Hansen, director of the Niels Bohr Institute at the University of Copenhagen, they prefer to identify an interesting area and build up a wealth of knowledge and expertise in it. For example, he […]
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