Hamilton came to her conclusions after studying the writings of female scientists over the past two and a half thousand years, and reading descriptions of women scientists by others. She analysed the diaries of scientists such as Sofie Brahe (the sister of the astronomer Tycho Brahe) and Henrietta Swan Leavitt, and compared their experiences with […]
A collision with a Near-Earth asteroid is believed to have wiped out the dinosaurs 65 million years ago. Near-Earth asteroids are usually piles of rock from the Mars-Jupiter asteroid belt whose orbit has been disturbed by a collision in the asteroid belt or by the gravitational pull of Jupiter. As asteroids are exceptionally faint visible […]
Black holes are usually detected by the effects of their vast gravitational field on the orbits of nearby astronomical objects such as stars. Naked black holes have no such material near them making it practically impossible to detect these objects. However, when a black hole drifts in front of distant star – as seen from […]
Since the US stopped testing in 1992 it has relied on the “stockpile Stewardship” programme to maintain the reliability and safety of its nuclear weapons. But a number of misconceptions were spread by the lab directors when they testified to the Senate hearings on the CTBT, argues Gottfried. He says the directors alleged that the […]
One of my initial goals when I enrolled on my teacher-training course at Warwick University in 1996 was to develop a portfolio of demonstrations that would entertain, interest and also educate a class of 30 watchful pupils. As the course progressed and the practical workshops started, the tutors shared their experiences with us “pen-poised” student […]
Adaptive-optic telescopes differ from normal telescopes by using a thin flexible primary mirror that can easily be deformed. A bright guide star near the observing area acts as a “beacon” for the telescope. As the image of the bright star is affected by turbulence, the primary mirror is distorted by computers to correct for the […]
NAUTILUS was designed to observe the gravitational waves produced by collisions between objects such as black holes or neutron stars. According to the Frascati’s group calculations, signals from such events could be masked by cosmic-ray showers. To take this effect into account they surround the cylinder with 116 cosmic ray detectors. When the aluminium cylinder […]
Bose–Einstein condensates are trapped atoms that are cooled to low temperatures and occupy the same quantum state. They are ideal for studying and manipulating quantum effects such as solitons and vortices as they occur on the macroscopic rather than the microscopic scale. In both of the new experiments the soliton waves moved through the BECs […]
Read article: Nuclear physics with lasers
About 20 years ago Toshi Tajima and John Dawson, then at the University of California at Los Angeles, suggested that laser-produced plasmas could be used to accelerate particles to high energies. The essential feature of their proposal was that the electrons would be accelerated by plasma waves moving at close to the speed of light […]
Two of the outstanding challenges in physics identified in our millennium survey last month were the nature of “dark matter” and a proper understanding of nuclear structure. This month we look at these challenges in greater detail. Dark matter is matter that does not interact with electromagnetic radiation: it cannot be seen with telescopes and […]
