Astronomers propose searching for alien planets by looking for 'vampire-repellent' chemicals in their atmospheres.
April 1, 2026
Original Paper
Plan 9: Detecting Atmospheric Deterrence Against Interstellar Monsters
arXiv · 2603.28895
The Takeaway
This study explores whether advanced civilizations might intentionally release gases like garlic-scented organosulfur to protect against folklore-inspired predators. It suggests that a 'stinky' or unusually bright atmosphere might be a sign that an alien biosphere has successfully defended itself against its own versions of monsters.
From the abstract
Exoplanet atmospheres are usually discussed as tracers of climate, chemistry, and habitability, but they may also preserve signatures of planetary defense. We consider three folklore-motivated deterrents against monsters: reduced organosulfur gases as anti-hematophage repellents, argentiferous reflective aerosols as anti-lycanthropic countermeasures, and haline aerosols as a counting problem for specters. We show that globally-mixed garlic-smelly levels of DMS/DMDS could produce observable mid-i