Pulsars are some of the strangest and least understood objects in the universe. These city-sized stellar cores are not only as dense as a backpack stuffed with Mount Everest, but also can spin as fast as a top. Furthermore, thanks to their insanely powerful magnetic fields, pulsars energetically funnel particles to their poles, which emit extremely intense, narrow beams of high-energy light.These bursts of deadly radiation (plus surges of other damaging particles) make the idea of living around a pulsar seem laughable. However, for the first time, astronomers have determined what it would take for a habitable exoplanet to survive the harsh conditions of a pulsar system. And as it turns out, it only takes an atmosphere — albeit a very (very) thick one.In a study published December 20 in the journal Astronomy & Astrophysics, researchers calculated that the habitable zone — the region around a star where liquid water can exist — for an exoplanet around a pulsar could be as large as the orbit of Earth around the Sun. However, the researchers stressed that this requires the pulsar’s planet be a super-Earth, capable of sustaining an atmosphere up to a million times as thick as our own.The first confirmed detection of any exoplanet came way back in 1992 with the discovery of multiple terrestrial-mass planets orbiting the pulsar PSR B1257+12, located 2,300 light-years away in the constellation Virgo. Three rocky exoplanets are now known to orbit this pulsar, and two of them are super-Earths (each weighing roughly four times the mass of Earth). But could any of these exoplanets really be habitable?