Pre-existing space structures trap electrons near shocks, making acceleration more efficient.

In space, giant shock waves from the Sun can push electrons to super-fast speeds, but seeing huge surges of high-energy electrons from these shocks is rare. Scientists do not fully understand how older space structures help cause these big jumps. To find out, researchers studied nine shocks recorded by the STEREO spacecraft. They tracked how the shocks moved through older space storms, known as coronal mass ejections, and interaction regions between different solar wind streams. They found that older structures act like giant magnetic traps. When a shock enters an earlier storm, closed magnetic loops trap electrons in front of it. Instead of escaping, the electrons bounce around near the shock face and gain far more energy. The team discovered that these pre-existing structures set up the surrounding space environment, keeping electrons trapped longer and dramatically boosting how well the shocks can speed them up.

Why it matters

This matters for space weather forecasting because enhanced electron radiation can damage satellites and disrupt communications. Understanding what conditions lead to these enhancements helps improve predictions and protect space assets.

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