This is a series of images of the one-million-degree solar corona in the extreme ultraviolet taken by the SOHO’s Extreme ultraviolet Imaging Telescope (EIT) in November 2003.

In the first panel, hazardous solar activity is only minutes away. Another SOHO instrument, the Comprehensive Suprathermal and Energetic Particle Analyzer (COSTEP), monitors space for electrons from the Sun.

In the second panel, a solar flare indicates the presence of ionising radiation on the Sun. This event sets free light-speed electrons that hurtle toward Earth. At the same time, COSTEP measured electrons arriving in our planet’s neighborhood. Such fast electrons are the first sign of possibly severe particle storms.

Tens of minutes later, a major solar ion event unfolded at Earth. This can be seen in the third panel. Human explorers and spacecraft systems are particularly susceptible to ionising radiation. Energetic protons hit the sensitive charge-coupled devices (CCDs) of the EIT, resulting in a “snowstorm” effect. Humans in space would need protection at this time.

Note: The third image has been enhanced for emphasis.

Individual images that make up the composite are available below:

Image1.jpg, Image2.jpg, Image3.jpg