Life around an ill-tempered red dwarf star is no fun for accompanying newborn planets. Call it a baptism of fire. Entangled magnetic fields cause a red dwarf to spit out "super-flares" that are 100 to 1,000 times more powerful than similar flares seen on our Sun. That is coupled with blistering ultraviolet radiation requiring any of the star system's inhabitants to use "Sunscreen 5,000." One of the nearest and most violent examples is AU Microscopii. The petulant star is only 1% the age of our Sun. At a distance of 32 light-years, it is only eight times farther away than the nearest star to our Sun, Proxima Centauri (which is another red dwarf).

The star beats-up the system's innermost planet, AU Microscopii b, which is about four times Earth's diameter. Orbiting just 6 million miles from the evil star's "dragon’s breath," the planet's largely hydrogen atmosphere is being stripped off, as viewed by the Hubble Space Telescope. But this happens in fits and starts. During one passage of the planet across the face of its star, Hubble detected hydrogen boiling off to create a large cloud ahead of the planet. This unexpected variability is evidence that the interaction between the planet and the red dwarf's feisty fireworks is probably more complex and unpredictable than imagined.