The Heoliosphere

This is a story that has popped up in a variety of media sources and on the blogosphere – including Science Daily. This version of the story is at www.latimes.com/news/science/la-sci-cosmic-rays-20101001,0,454358,print,stp the web site of the Los Angeles Times, and concerns the IBEX satellite orbiting the Earth in order to study the solar system heliosphere, the invisible bubble that exists beyond the planets. The heliosphere is thought to shield the solar system from ninety per cent of cosmic rays – deflecting them. The solar wind pours out to the limits of the bubble and interaction with cosmic rays produces uncharged particles – they are effectively neutralised and stream back into the solar system. The satellite was launched in 2008 with the intention of collecting and analysing the uncharged particles. It maps the heliosphere as it circles the Earth as our planet travels around the Sun – and already it is coming up with big surprises. For example a huge loop or ribbon of high energy particles appears to exist between the centre and the outer section of the heliosphere, with an unusually bright spot in the northernmost section of the loop – almost like aurorae. However, the news story is not that but the fact that after just two years of observation scientists have discovered the heliosphere has shrunk. It has also allowed more cosmic rays to enter the solar system as a result – or this is the gloom prediction. One or the other. They are amazed by the short-scale changes they have witnessed and it is thought the lack of sun spots is probably to blame. Once activity on the Sun is reignited they expect to see further surprises – and it is amazing the amount of information about our immediate location in space that has been discovered by the plethora of cameras and telescopes now in use.