Astronomers have discovered that sulfur may be a key to helping us narrow down our search for life on other planets. It's not that sulfur is a great indication that a planet is inhabited. Instead, it's the opposite: Significant amounts of sulfur dioxide in a planet's atmosphere is a good sign that the world is uninhabitable and we can safely cross it off the list of candidates.
One of the holy grails of modern astronomy is finding life on an alien planet. But that is an extremely daunting task. The James Webb Space Telescope is unlikely to be able to identify biosignatures — the atmospheric gases produced by life — in any nearby worlds. And the upcoming Habitable Worlds Observatory will be able to scan only a few dozen potentially habitable exoplanets.
