In addition to being wonderful fodder for blockbuster movies, this scenario was also the inspiration for a tabletop exercise with NASA scientists at the International Academy of Astronautics' Planetary Defense Conference last week. More bad omens emerged on day three of the simulation, which fast-forwarded to International Asteroid Day on June 30: The asteroid was predicted to crash somewhere inside the relatively populated region of central Europe. Image: Google Earth/ International Academy of Astronautics (IAA) 2021 Planetary Defense ConferenceThat said, the tabletop exercise demonstrated that even worst-case scenarios still present many opportunities to mitigate casualties and damage. DART will slam into a small asteroid that is orbiting a larger asteroid, in a system known as Didymos, providing a safe way to experiment with this planetary defense strategy. Missions such as NEOSM are designed to prevent the types of imminent emergencies presented in the latest tabletop exercise by providing scientists with ample time to prepare for dangerous encounters.