Physics and Astronomy

One lump of rock is revealed as two in the distant Kuiper belt.

The stand-offish dance of two asteroids at the outer reaches of the Solar System is captivating astronomers. The two rocky objects, discovered locked in mutual orbit, could tell us about the properties of the far-flung Kuiper belt.

Christian Veillet and his team 1 studied an object called 1998 WW31 in the Kuiper belt, a sparsely populated region of space beyond the orbit of Neptune. The object w

Between now and Saturday, 20 April, you can follow via the Internet the progress of the new-found Comet SOHO-422. Usually, comets seen by the SOHO spacecraft quickly burn up in the Sun’s hot atmosphere. This one won’t, so there is still time to monitor its progress.

Like most of the hundreds of comets found with the ESA-NASA sun-watching spacecraft, SOHO-422 was first noticed by an amateur astronomer. Pictures from SOHO are made available, freely and rapidly, on the Internet. Peop

Random vibrations can generate rotation.

A simple top converts foghorn noise to one-way spin. The device raises the hope that useful energy could be collected from ambient sounds. Normally, random vibrations, which physicists and engineers call noise, produce useless random motion. You can’t move a cart from A to B by shoving it randomly in every direction.

But in the new device, made by Yaroslav Zolotaryuk of the Technical University of Denmark in Lyngby and colleagues

The first steps in a new method of detecting landmines by determining the presence of tiny quantities of the explosive TNT (trinitrotoluene) are described in research published today in the Institute of Physics publication Journal of Physics D. Markus Nolte, Alexei Privalov and Franz Fujara of Darmstadt Technical University in Germany, together with Jurgen Altmann of Dortmund University and Vladimir Anferov from the Kalingrad State University in Russia, describe in the journal how they have devised a

In the past five weeks two asteroids have passed close by Earth, at distances of 1.2 and 3 times the distance to the Moon. Another asteroid has recently been shown to be on course for a collision with Earth in 2880.

Monitoring known asteroids allows astronomers to predict which may collide with Earth. But that is only true for the asteroids we know of. What about those that lie in the asteroid blind spot between the Sun and Earth? The European Space Agency is studying ways in which its miss

Astronomers probing the intimate details of apparently quiescent stellar black holes have discovered that in reality they are dynamic, lively places, subject to flares that briefly illuminate the whole of the gas disc around the black hole. Their observations are helping to build up a picture of precisely where X-rays are generated in the gas as it heats up to extreme temperatures and swirls around under incredible gravitational forces before cascading into the black hole itself. On Friday 12 April,