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Astronomy

The Influence of Planetary Magnetic Fields on Atmospheric Escape

Quick fact

Mars likely had a global magnetic field around 4 billion years ago, but after it faded, the solar wind stripped away much of its atmosphere, transforming it from a warm, wet planet into the cold desert we see today.

Why this is interesting

You know Earth has a magnetic field, the one that makes compasses point north. But what if that gentle, invisible field is also the invisible force keeping our atmosphere from drifting off into space?