SKAMANIA COUNTY, Wash. — What looks like a quiet, snow-covered forest near Trout Lake holds a surprising secret just beneath the surface. Instead of a dirt trail, the journey begins with a trek deeper ...

From lava tubes on Mars to ice pockets on Europa, subterranean environments may offer the best chance of finding life—and living safely—beyond our planet. “I was like, ‘OK, I'm pretty sure that ...