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Astronomy

The Influence of Galactic Magnetic Fields on Cosmic Ray Paths

Quick fact

The Milky Way's magnetic field is only about a few microgauss (roughly 100,000 times weaker than Earth's surface field), yet it is strong enough to trap and scatter cosmic rays for millions of years, erasing their original direction.

Why this is interesting

You might think cosmic rays zoom straight across the galaxy, but they actually arrive from all directions at once—as if the galaxy is stirring them like cream in coffee. What invisible force is mixing them up?