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Venus has a weak magnetic field. Being much closer to the Sun than Mars, why has the solar wind not eroded its atmosphere?

Michael Rodriguez, Corvalis, Oregon
RELATED TOPICS: VENUS
Venus
One major reason is that Venus has a lot more atmosphere than Earth. So even though Venus is losing some atmosphere to space all the time — at about the same rate as Earth — that loss does not have much effect on the overall density or surface pressure. (Although over time it has likely affected the atmosphere’s composition.)

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