29 June 2009
Sun leaves Earth wide open to cosmic rays
Posted by Jimmy under: Earth; Science .
Our sun periodically leaves Earth open to assaults from interstellar nasties in a way that most stars do not. How can this be you ask? The sun protects us by a kind of force field called heliosphere – a bubble of solar wind that extends past Pluto. As we travel through space, the solar system passes through very dense gas and dust clouds, the heliosphere can shrink until its edge is inside Earth’s orbit. The cosmic rays would damage the ozone layer, and interstellar dust could dim sunlight and trigger an ice age.
