The sad magnetic state of the solar system’s rocky worlds
![Aurora](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2015/09/081915_ts_aurora_free.jpg?fit=860%2C460&ssl=1)
PLANETARY PROTECTION Earth’s magnetic field deflects charged solar particles toward the planet’s poles, generating auroras. This photo was taken from (and shows parts of) the International Space Station.
Above: NASA; Below, from top: NASA, JHUAPL, Carnegie Inst. for Science; JPL-Caltech/NASA; NASA; JPL-Caltech/NASA