SpaceX plans for Starship’s 13th flight to take off as early as July 16, and for the first time the vehicle will carry a real payload—20 Starlink V3 satellites—making Starship more than a test prototype.
The same week, NASA is assembling a very different machine at Kennedy Space Center: the Space Launch System for Artemis III, the crewed Moon landing now set for 2027. The SLS is a formidable rocket—in April it carried the Artemis II crew farther from Earth than any humans have ever traveled—but it costs some $4 billion a launch and runs 140% over budget, and the administration means Artemis III to be one of its last flights, pivoting to commercial rockets, while Congress fights to keep the legacy program alive.
The relationship is more than rivalry. Starship, the reusable vehicle now beginning to carry cargo, is the very lander NASA has contracted for Artemis III—but for now only SLS can send Orion and its crew toward the Moon. Starship can reach orbit with Orion’s mass, yet to go farther it must be refueled there by a string of tanker flights, a capability still unproven. The administration is betting Starship will grow into the whole mission and let the throwaway rocket be retired for good.
But this argument is thinking far too small. Both machines burn chemical propellant—and chemistry is near its ceiling, the best hydrogen engines topping out around 450 seconds of specific impulse. The leap that would actually open the solar system is nuclear. In the 1960s the NERVA program ground-tested nuclear-thermal engines at 825 seconds, nearly double the chemical limit—and we canceled them in 1973. This March we did it again, killing the DARPA-NASA DRACO nuclear demonstrator on the reasoning that cheap chemical launch had made it unnecessary. Twice now we have had programs for advancing nuclear propulsion, and we let it go—the second time using reusability itself as the excuse. The question underneath the budget fight is not throwaway versus reusable. It is whether a civilization that means to live in space will ever climb the one rung that matters: from chemical to nuclear energy-flux density, and beyond it to fusion.