Mark Cuban never met the founder. He never toured the facility. He simply read an email and wired half a million dollars. That decision, made years ago with little more than instinct, now sits at the center of one of the aerospace industry’s most watched contests. Relativity Space, the company Cuban backed, stands today as a serious rival to SpaceX. Its valuation hovers near $4 billion. It holds nearly $3 billion in customer orders. And its first orbital rocket aims for flight before the year ends. The story began with a cold pitch. Tim Ellis, a former Blue Origin engineer who once ran the company’s metal 3D-printing efforts, reached out from Dallas. He and his partners wanted to build rockets faster and cheaper than anyone thought possible. Cuban knew next to nothing about space. His reply was blunt. “I don’t know shit about space, but I’ll get you started and see what happens,” he later recalled in a September 2024 interview with podcaster Theo Von. The entire relationship stayed digital.…