June 3, 2007

Forecasting Solar Storms

A new way to predict solar storms has been developed by the physicist Arik Posner, using the SOlar and Heliospheric Observatory (SOHO), and can give as much as one hour advanced warning for astronauts in space to seek shelter. This is a very important breakthrough, especially for astronauts, because these dangerous storms had been very hard predict before.

Solar radiation storms are bursts of electrons, protons, and heavy ions accelerated by massive explosions on our Sun. Our Earth's atmosphere and magnetic field protects us from these massive bursts; even astronauts in Earth orbit, the magnetic field reaches far enough to protect them. But when, astronauts leave this field, like on future trips to the Moon and Mars, they are in danger; neither of these objects contains a global magnetic field. However, a one hour warning can be very beneficial, providing enough time to seek proper shelter until the threat is over. This warning can also help satellites as well. Solar radiation storms can cause the satellite's computers to malfunction and reboot, but prior warning can allow a safe mode to be turned on.

The most dangerous particles are ions, atoms that have lost one or more of their electrons. They can damage tissue, break strands of DNA, and lead to diseases like cancer. Posner's way to detect these are to use electrons which are always detected before the ions. This had been previously known, but Posner used this information to forecast solar storms.

In all storms, a mix of electrons, ions, and protons are released, and the electrons, being the smallest particles, reach Earth first. Posner discovered that by measuring the "rise time and intensity of the initial electron surge," he could be able to tell how many ions are arriving and when.

Posner came to this conclusion by using the COSTEP (COmprehensive SupraThermal and Energetic Particle analyzer) on the SOHO spacecraft. This device counts the particles coming from the sun and measures their energies. Posner constructed a predictive matrix using the record of the numerous solar storms recorded by COSTEP from 1996 to 2002. To test this matrix, Posner tested it on COSTEP data from 2003; it successfully predicted all of the solar storms that took place in 2003, with it providing advanced warnings from anywhere between 7 and 74 minutes. However, the method is not yet perfect, providing false alarms for weak storms or no storms at all. Posner is perfecting this method with the massive amounts of data available from COSTEP, which was launched in 1995.

This method is under consideration by Johnson Space Center for future lunar missions. It will help protect astronauts from these dangerous storms, helping mankind reach further into space.

For more information, visit:

No comments:

Post a Comment