Of the many enabling capabilities that will make NASA’s next crewed lunar landing possible, only orbital cryogenic propellant transfer has never been done in space and will be pivotal to SpaceX’s Starship HLS reaching the Moon. That single fact underscores the scale of the engineering challenge now pushing the Artemis 3 mission more than a year past NASA’s target date.
An internal SpaceX schedule that Politico obtained shows the company is aiming for a crewed lunar landing in September 2028, well beyond NASA’s goal for mid-2027. It all depends on two critical milestones: an orbital propellant transfer test scheduled this coming June 2026, and an uncrewed lunar landing scheduled for June 2027. Both are absolutely essential before the HLS can ferry astronauts to the lunar surface; neither has been demonstrated so far. As Paul Hill with NASA’s Aerospace Safety Advisory Panel mentioned after a visit to SpaceX’s Starbase, “The HLS schedule is significantly challenged and, in our estimation, could be years late for a 2027 Artemis 3 moon landing.”
Starship’s road to readiness has been a bumpy one. The vehicle began flight testing in 2023, amassing some impressive firsts – catching a Super Heavy booster with its “Mechazilla” arms and performing soft ocean touchdowns with its Ship upper stage among them – but three of five launches in 2025 ended in failure of the upper stage during ascent or reentry. Only later-year flights of the “Block 2” version showed consistent stability. The upcoming Version 3 – bigger and more capable – will be the first able to attempt cryogenic propellant transfer: a challenging process in which liquid methane and liquid oxygen must be transferred in microgravity without excessive boil-off. SpaceX estimates the lunar lander may need as many as 12 tanker flights to fully fuel for a mission to the Moon.
Changes to NASA’s own schedule aptly reflect the challenge of integrating new systems. Artemis II, the first crewed Orion flight around the Moon, is now targeted for September 2025. Artemis III has revised plans in concert with a variety of lessons learned from Artemis II and incorporates delays from industry partners, including SpaceX’s HLS and Axiom Space’s next-generation lunar spacesuits. “We are letting the hardware talk to us so that crew safety drives our decision-making,” said Catherine Koerner, associate administrator for Exploration Systems Development.
The delays have strategic implications. Acting NASA Administrator Sean Duffy has reopened the Artemis 3 lander contract to competitors, citing the need to beat China’s planned crewed lunar landing by 2030. Blue Origin, already contracted for Artemis 5, is positioning its Blue Moon Mark 1 and Mark 2 landers as alternatives. The Mark 1, an 8.1-meter-tall cargo lander powered by BE-7 engines, can reach the Moon without refueling and is slated for an uncrewed demo in early 2026. The larger Mark 2, designed for crewed missions, will require its own orbital cryogenic transfer system, the Lunar Transporter, which has been undergoing thermal vacuum testing at NASA’s Marshall Space Flight Center.
That incremental approach taken by Blue Origin could, if adapted from cargo configurations, provide NASA a quicker path to a crewed landing. “We have what we think are some good ideas about maybe a more incremental approach that could be taken advantage of for an acceleration-type scenario,” said Jacqueline Cortese, the company’s Senior Director of Civil Space.
Where SpaceX has an advantage is in terms of manufacturing scale and flight cadence. The quick turnaround of Falcon 9 has given the company “unprecedented experience in spacecraft and booster manufacturing, launch preparation and flight operations,” Hill noted. Yet those same resources are split between Starship HLS and other priorities, like launching Starlink V3 satellites. The next six months of Starship Version 3 flights will be crucial in determining whether SpaceX can hit even its revised 2028 goal.
The Artemis 3 technical road is clear but steep: execute orbital cryogenic transfer without boil-off losses, conduct an uncrewed lunar landing, and integrate the HLS with Orion for crew return. Each one represents a first-of-its-kind accomplishment in spaceflight. Until those are achieved, the first NASA crewed lunar landing since Apollo will remain over the horizon – and the Moon will wait just a little longer.
