It looks like someone spilled a chemistry set across the surface of another planet. But this is Earth, roughly 125 meters below sea level, in the Danakil Depression of northern Ethiopia. Dallol sits at one of the few places on the planet where three tectonic plates are slowly pulling apart at the Afar Triple Junction. As the crust stretches and thins, magma rises close to the surface and superheats groundwater percolating through thick buried deposits of salt. The result is a hydrothermal field unlike anywhere else on the planet. What makes Dallol so alien is that nearly every extreme condition life can face shows up here at once: • Heat: it ranks among the hottest places on Earth by year-round average temperature, sitting around 34 to 35°C annually, with daytime highs that punish anything exposed. • Acidity: springs bubble up brines with a pH at or below zero, rivaling battery acid and then some. • Salt: the waters are hypersaline, saturated with sodium, magnesium, and iron salt...