Kelvin–Helmholtz waves may help the solar wind strip atmospheric particles from Mars.

Mars is continually exposed to a stream of charged particles racing outward from the Sun. Earth’s global magnetic field deflects much of this solar wind, but Mars lacks a comparable shield. The flow can therefore strike the planet’s upper atmosphere directly and gradually carry some of its particles into space.

Researchers led by Boston University have identified one way this atmospheric loss may occur. Their study, published in Science Advances, found that the solar wind can disturb the outer edge of the Martian atmosphere much as wind agitates the surface of water. The interaction produces large rolling structures called Kelvin–Helmholtz waves, which can help pull atmospheric material away from the planet.