With each new crew launch from the U.S. comes the inevitable questions: Why all the weather rules? What are the vehicle’s abort modes and how will it perform a launch abort and aim itself to a predetermined location in the Atlantic Ocean stretching from the Kennedy Space Center across to the western Irish coast?

The Crew-1 mission of SpaceX’s Dragon 2 capsule is contending with these questions, with its launch already delayed from Saturday because of weather. The mission is currently set to launch at 19:27 EST (00:27 UTC) on Sunday, 15 November (Monday, 16 November UTC) from LC-39A in Florida to bring Mike Hopkins, Victor Glover, Shannon Walker, and Soichi Noguchi to the International Space Station.

Why do NASA, the 45th Space Wing of the Space Force, their safety officers, and all launch providers make such a big deal about the weather? Who cares if it’s raining 18 km from the pad when the safety rules say rain cannot be closer than 18.5 km? Isn’t that close enough?