Why NASA’s hopes of returning to the moon before China gets there hinge on SpaceX

This elaborate and complex sequence hinges on a number of unproven technologies; chief among them is the need to refuel Starship as it waits in space. Dreier said it’s not yet clear how many launches will be needed to transport the necessary fuel, but they would have to occur in rapid succession.

“Anywhere from a dozen to maybe 20 refueling launches within a month would be needed to refill Starship’s tanks in order for it to have enough energy to send itself to the moon and come back,” he said. “That’s never been done before.”

Refueling in space alone would require “huge advancements” from where Starship is now, he added.

“It’s a massive, massive challenge,” Dreier said. “And without all that, you don’t get to the moon.”

The Starship lander is expected to tower nearly 150 feet over the stout, spidery-looking moon landers that NASA used in its Apollo program. This taller design enables Starship to haul more passengers and cargo, but it could also make the spacecraft less stable than its Apollo counterpart.

Still, it wouldn’t have made much sense for NASA to fall back on old technologies, Dreier said, in part because of cost. A single liftoff of the Saturn V rocket NASA used for the Apollo flights would cost about $2 billion today. SpaceX, on the other hand, aims to make Starship fully reusable, which would lower costs and shorten turnaround times between launches.