Radiation will be a real challenge for Mars colonists, powerful solar storms show

The same giant sunspot responsible for creating a historic geomagnetic storm on Earth in mid-May produced a legendary storm for Mars a few days later.

On May 20, data from the European spacecraft Solar Orbiter showed that an estimated X12 solar flare - the strongest type on the flare rating scale - erupted from sunspot AR3664 (which was renamed AR3697 during its second trip around the Sun). A powerful one coronal mass ejection (CME) followed and sent a huge cloud of super-hot solar plasma towards Mars at millions of kilometers per hour.

The consequences of this solar event provided quite ...