Astronauts venturing beyond the protective magnetic field of Earth face the direct effects of the Sun and unpredictable outbreaks of activity.
Within even one hour, explorers can be engulfed with particles that cause harmful long- or short-term health effects and put missions at risk. “Going Outside” requires a space weather warning system.
New research has shown that electrons traveling at the speed of light are always present in solar particle eruptions. These electrons – traveling much faster than the hazardous solar energetic protons – follow the magnetic lines of force from the Sun to the Earth.
Therefore, they can be used as an reliable early warning sign of hazardous radiation ahead.
Reference: Posner, A., Up to 1-hour forecasting of radiation hazards from solar energetic ion events with relativistic electrons, Space Weather, Vol. 5, S05001, doi:10.1029/2006SW000268, 2007.
This site distributes the live SOHO/COSTEP warnings. SOHO is a project of international cooperation between ESA and NASA.