Ash, magma and lightning during an eruption of the Sakurajima volcano in southern Japan that occurred in early January Why lightning occurs in thunderstorms is a topic of research; why it occurs in volcanic eruptions is even less understood.
April 6, 2009--A new x-ray image has revealed an unusual hand-shaped nebula that brings a whole new meaning to the expression "reach for the stars." Known as B1509, the pulsar is thought to be about 1,700 years old and lies roughly 17,000 light-years from Earth. The tiny pulsar is just 12 miles (19.3 kilometers) wide. But it is spinning so fast—it makes seven complete rotations every second—that the particles it spews have created a nebula spanning 150 light-years.