The crew vehicle is set for blastoff from NASA's Kennedy Space Center atop one of Musk's reusable Falcon 9 rockets, with a 24-hour targeted launch window that opens at 8 pm EDT (0000 GMT) on Wednesday. That window will be narrowed, or possibly altered, a few days before, depending on weather.
Dubbed Inspiration4, the orbital outing was conceived by Isaacman primarily to raise awareness and support for one of his favorite causes, St Jude Children's Research Hospital, a leading pediatric cancer center. He has pledged $100 million personally to the institute.
But a successful mission would also help usher in a new era of commercial space tourism, with several companies vying for wealthy customers willing to pay a small fortune to experience the exhilaration of supersonic flight, weightlessness and the visual spectacle of space.
Setting acceptable levels of consumer risk in the inherently dangerous endeavor of rocket travel is also key, and raises a pointed question.
"Do you have to be both rich and brave to get on these flights right now?" said Sridhar Tayur, a professor of operations management and new business models at Carnegie Mellon University in Pittsburgh, in an interview with Reuters on Friday.