aug 062012
 
How Accurate are the Models of Star- and Planet Formation?

  Stars form when gravitational forces coalesce the gas and dust in interstellar clouds until the material forms clumps dense enough to become stars. Precisely how this happens, however, is still very uncertain. The infall of matter is probably not symmetric, it may be inhibited by the pressure of very hot radiation around the young [continue reading]

apr 072012
 
Measuring Magnetic Fields

Polarized light is a familiar phenomenon, as people who prefer polarized sunglasses can testify. The electric field in a beam of light can vibrate either left-right or up-down, and the scattering or reflection of light can result in the preferential absorption of one or the other of these two “polarizations.” The majority of sunlight on [continue reading]