Tuesday, August 3, 2010

Today's Hot News

The Sun as You've Never Seen It Before
The sun's surface erupted early Sunday, blasting  tons of plasma into space -- and right at the Earth. Astonishing new pictures from NASA show the giant flares and clouds of ionized gas erupting from the star.

Sudden intense brightening of a small part of the Sun’s surface often near a Sunspot group is termed as Solar Eruption or Solar Flare. Flares develop in a few minutes and may last several hours, releasing intense X rays and streams of energetic particles. They appear to be connected with changes in the Sun's magnetic fields during the Solar Cycle. The ejected particles take a day or two to reach the vicinity of Earth, where they can disrupt radio communications and cause auroras and may pose a radiation hazard to astronauts.
A solar flare is a large explosion in the Sun’s atmosphere that can release as much as 6 × 1025 joules of energy. The term is also used to refer to similar phenomena in other stars, where the term stellar flare applies.
Solar flares were first observed on the Sun by Richard Christopher Carrington and independently by Richard Hodgson in 1859 as localized visible brightening of small areas within a sunspot group. Stellar flares have also been observed on a variety of other stars.
Scientific research has shown that the phenomenon of magnetic reconnection is responsible for solar flares. Magnetic reconnection is the name given to the rearrangement of magnetic lines of force when two oppositely directed magnetic fields are brought together. This rearrangement is accompanied with a sudden release of energy stored in the original oppositely directed fields.
Solar flares strongly influence the local space weather of the Earth. They produce streams of highly energetic particles in the solar and the Earth's magnetosphere that can present radiation hazards to spacecraft and astronauts.