Young stars ejecting plasma could give us clues into the Sun’s past Kyoto, Japan — Down here on Earth we don’t usually notice, but the Sun is frequently ejecting huge masses of plasma into space. These are called coronal mass ejections (CMEs). They often occur together with sudden brightenings called flares, and sometimes extend far enough to disturb Earth’s magnetosphere, generating space weather phenomena including auroras or geomagnetic storms, and even damaging power grids on occasion. Scientists believe that when…
Physicists at the University of Bonn build quantum data memory
Physicists from the University of Bonn have succeeded in taking a decisive step forward towards processing quantum information with neutral atoms: in the latest issue of the ’Physical Review Letters’ vol. 93 (2004) they describe how they managed to set up a quantum register experimentally. Their next aim is to construct a quantum gate in which two or more atoms interact with each other in a controlled way. By combining th
Scientists at the Lawrence Livermore National Laboratory have discovered a new melt curve of hydrogen, resulting in the possible existence of a novel superfluid – a brand new state of matter
As reported in the Oct. 7 edition of the journal Nature, the researchers present the results of ab initio calculations of the hydrogen melt curve at pressures up to 2 million atmospheres.
The measurement of the high-pressure phases of hydrogen has been the focus of numerous experiments
Tracking newly discovered asteroids and comets to identify their orbits is the work of a small number of observatories. Yet UK students, using the Faulkes Telescope North – a remotely operated research quality telescope dedicated for educational use – will now be swelling these ranks. The students have taken such accurate data of a number of asteroids that the telescope has been awarded an observatory code and can now submit official data to the international body that monitors asteroids and comets,
An asteroid 2.9 miles long and 1.5 miles wide zoomed past Earth Sept. 29 and came within 962,951 miles of the planet. While this might not seem like a near miss, technically it is relatively close – merely four times the distance between Earth and the moon.
But, it’s not likely that a large space rock like this one would actually hit Earth in our lifetime, says physics professor Perry Gerakines, Ph.D. “The odds that an asteroid of this magnitude would impact the Earth are in the millions t
Many accidents, especially at night, are caused by motorists having to take their eye off the road as they look down to see the car instruments. Head-up displays would be a solution, were they not so expensive and bulky. OEDIBUS has an innovative solution.
Driving at night is dangerous. Research shows that, although less than one third of all driving is done at night, over 50 per cent of the fatalities occur during this period. For pedestrians, 60 per cent of fatalities occur during the hours
Research carried out by scientists at the University of Surrey could lead to a significant decrease in the number of pedestrians and cyclists killed each year on Europe’s roads. In-car systems have significantly improved safety for drivers and passengers, and the introduction of soft bumpers and pop-up bonnets has lowered the risk of injury to pedestrians and cyclists, but a system of new sensors currently being developed, could potentially lower the fatality rate even further.
Over 6
A team of UK scientists has used, for the first time, an extremely short-pulse laser to accelerate high-energy electrons over an incredibly short distance. Current accelerators can be hundreds of metres long, this is just a millimetre long.
Earlier laser-driven accelerators were inefficient, accelerating the electrons to a wide range of energies. But scientists who wish to use these electron beams to research materials science – such as the structure of viruses and moon rock – nee
Scientists from the UK and the USA have successfully demonstrated a new technique that could help to shrink the size and cost of future particle accelerators for fundamental physics experiments and applications in materials and biomedicine.
Using the huge electric fields in laser-produced plasmas, they have accelerated beams of electrons close to the speed of light, in an important step towards the development of a working laser electron accelerator that could sit on a table top.
The electrons of a perfect metallic surface move like free waves in a plane. Nevertheless, if atomic barriers are inserted, this may restrict their movement in one dimension, forming stationary waves such as those on the water surface in a bucket.
The stationary or free behaviour of electron waves is, nevertheless, still something very intriguing, given that the barriers of atoms are very close to each other, there is no confinement, and that the electron recovers its free movement
Computer models of Earths climate have consistently linked long-term, high-magnitude variations in solar output to past climate changes. Now a closer look at earlier studies of the Sun casts doubt on evidence of such cycles of brightness, their intensity and their possible influence on Earths climate. The findings, by a solar physicist and two climate scientists funded by the National Science Foundation (NSF), appear in the October 1 issue of the journal Science.
“The relationshi
A new class of very small handheld devices can detect motion a thousand times more subtly than any tool known.
“There was nothing in the [optics] literature to predict that this would happen,” says Sandia National Laboratories researcher Dustin Carr of his groups device, which reflects a bright light from a very small moving object.
Sandia is a National Nuclear Security Administration laboratory.
Carr, who earlier gained fame as a graduate student at Cornell
Penn State researchers have developed a computer program that mimics the results when a human appraises a task as threatening and feels worried before starting.
Dr. Frank Ritter, associate professor in the School of Information Sciences and Technology (IST), says, “In this study, we used our program to mimic the results achieved by people who can be seen as having a type of math anxiety. However, the program could also be used to study the effects of feeling threatened or worried be
In a nod to scientific paradox, researchers at the University of California, Berkeley, have slowed light down in an effort to speed up network communication.
They have shown for the first time that the group velocity of light – the speed at which a laser pulse travels along a light wave – can be slowed to about 6 miles per second in semiconductors. While that speed is not exactly the pace of a turtle, it is 31,000 times slower than the 186,000 miles (or 300 million meters) per seco
A Supernova Early Warning System (SNEWS) that detects ghostlike neutrino particles that are the earliest emanations from the immense, explosive death throes of large stars will alert astronomers of the blasts before they can see the flash.
SNEWS “could allow astronomers a chance to make unprecedented observations of the very early turn-on of the supernova,” wrote the authors of an article about the new system in the September issue of the “New Journal of Physics” http://www.iop.org
Today, September 29, 2004, is undisputedly the Day of Toutatis, the famous “doomsday” asteroid.
Not since the year 1353 did this impressive “space rock” pass so close by the Earth as it does today. Visible as a fast-moving faint point of light in the southern skies, it approaches the Earth to within 1,550,000 km, or just four times the distance of the Moon. Closely watched by astronomers since its discovery in January 1989, this asteroid has been found to move in an orbit that bring
Astronomers have used an X-ray image to make the first detailed study of the behavior of high-energy particles around a fast moving pulsar. The image, from NASAs Chandra X-ray Observatory, shows the shock wave created as a pulsar plows supersonically through interstellar space. These results will provide insight into theories for the production of powerful winds of matter and antimatter by pulsars.
Chandras image of the glowing cloud, known as the Mouse, shows a stubby b