Are we ready for an asteroid impact? This October, NASA will conduct a drill to see how well its planetary defense system would work if an actual asteroid were heading straight for Earth. While these sort of drills have been done in the past with pretend asteroids, this one will feature a real asteroid, one that astronomers are confident will miss the Earth as it zooms by on Oct. 12. “The question is: How prepared are we for the next cosmic threat?” said Vishnu Reddy of the University of Arizona and NASA consultant. “So we wanted to test how ready we are for a potential impact by a hazardous asteroid,” he said.