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Both SpaceX and Blue Origin are companies that first and foremost have to make a profit, not lose money. SpaceX was profitable with Falcon-9/-Heavy, but has bet its future "farm" on rideshares with Starship/Superheavy. They still have their hands full just trying to make Starship/Superheavy work at all as a transport to LEO. Blue Origin has its hands full trying to make New Glenn into a profit center. Coming up with a contracted NASA lunar lander is a smaller piece of that overall larger puzzle, for both of them. I cannot fault their priorities.
Of the two, I suspect Blue Origin might be a little closer to satisfying the NASA lander contract. That is because SpaceX bit off a much-larger piece of "iffy" technology advancement, trying to do the all-reusable Starship/Superheavy. Plus, my reading of the events suggests the ratio of Musk time to real time (3 to 4) is a bit bigger than Bezos's ratio (2 to 3).
The time from lunar rendezvous being the adopted Apollo architecture in 1964 or 1965, to the Apollo-9 checkout of the Apollo CSM with its LM in LEO in 1969, was only 4 or 5 years! THAT is how long it took Grumman to come up with a workable lander, under a crash program where cost was no object. And higher risk-taking by NASA with its astronauts was "normal".
Artemis is NOT a crash program where cost is no object, and NASA (I hope) has learned not to take such extreme risks with its astronauts! Expecting SpaceX and Blue Origin to come up with anything workable as a lunar lander in only 4 years or so, is actually quite unreasonable! SpaceX started only 2-3 years ago, and Blue Origin "in earnest" only last year.
You CANNOT count the proposal and contract-win time, as real hardware development time! That only sets the concept they will focus upon. REAL development only starts AFTER contract award. And coming up with a concept has NOTHING to do with its development into something real! That's just life. Ugly, ain't it?
NASA projecting schedules that have no reality tells me there is no one there anymore that understands the difference between company time and real time, and that the ratio varies from company to company. I would expect that, after all the former traditional contractors agglomerated into monopolies that no longer really compete (with the government making no anti-trust moves to stop it). THAT is why "new space" has had such a hard time getting established. The game was rigged.
GW
Last edited by GW Johnson (2026-04-13 15:18:04)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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SpaceX targets Starship flight 12 as NASA eyes lunar-ready refueling demos
SpaceX is gearing up for Starship Flight 12, a mission that could mark a turning point in the company’s effort to prove orbital refueling works at the scale NASA needs for its Artemis lunar lander. As of late April 2026, the flight has not received a public launch date, but the stakes are already clear: until SpaceX can reliably transfer hundreds of tons of propellant between vehicles in orbit, no astronaut will ride Starship to the Moon.
The Artemis program’s entire lunar landing architecture depends on this capability. NASA’s published mission overview for Artemis III and IV describes a chain of events that must unfold before a crewed touchdown: SpaceX launches a propellant storage depot into Earth orbit, sends up a series of tanker flights to fill it, and then fuels a Human Landing System variant of Starship for its trip to the Moon. Only after that sequence is complete can Starship HLS leave orbit, rendezvous with NASA’s Orion capsule near the Moon, descend to the surface, and return crew safely. Orbital refueling is not an add-on. It is the load-bearing wall of the entire plan.What orbital refueling actually requires
The concept sounds simple: pump propellant from one spacecraft to another. In practice, it is one of the hardest unsolved problems in spaceflight at this scale. Liquid methane and liquid oxygen, Starship’s propellants, must be kept at cryogenic temperatures while being transferred between vehicles traveling at roughly 17,000 miles per hour. Boil-off, where warming fuel turns to gas and becomes unusable, is a constant threat. The two spacecraft must dock precisely, maintain stable orientation, and manage fluid dynamics that behave unpredictably in microgravity.NASA’s architecture calls for multiple tanker flights to fill a single depot, meaning the process must work not once but repeatedly and reliably. The agency has not publicly disclosed how many tanker launches are required or what failure rate it considers acceptable. Those parameters will shape whether the refueling campaign takes weeks or months, and whether a single tanker mishap can delay an entire Artemis mission.
SpaceX conducted propellant transfer experiments during earlier Starship test flights, including internal fluid movement tests that demonstrated basic plumbing in orbit. But transferring propellant between two separate vehicles at the volumes Starship HLS demands has not yet been demonstrated. Flight 12 is widely expected to push closer to that goal, though SpaceX has not confirmed the mission’s specific objectives.
The FAA’s incremental approval process
Every Starship flight must clear the Federal Aviation Administration’s regulatory process, and that process is deliberately incremental. The FAA evaluates each mission profile individually under the National Environmental Policy Act, examining trajectories, airspace closures, debris footprints, and safety corridors for aviation and maritime traffic. A change in reentry angle, landing zone, or on-orbit duration can trigger a new environmental assessment.
The agency’s stakeholder engagement portal for the Starship program hosts the environmental assessments and Finding of No Significant Impact documents that authorize specific flights from the Boca Chica launch site in South Texas. A tiered environmental assessment published for Flight 9 in 2025 illustrates the pattern: it addressed updated airspace closures, aircraft hazard areas, and overflight risks specific to that mission’s profile. Subsequent flights have followed the same framework, with each new configuration requiring its own review or falling within an already permitted envelope.For Flight 12, the regulatory picture is not yet public. If SpaceX plans extended on-orbit operations, ship-to-ship docking, or propellant transfer maneuvers that differ from previously cleared profiles, the FAA would need to evaluate those changes before granting a license. The agency operates on its own timeline, independent of SpaceX’s development pace or NASA’s Artemis schedule.
Artemis III and the schedule question
Artemis III, the mission intended to return astronauts to the lunar surface for the first time since Apollo 17 in 1972, has been a moving target for years. NASA continues to describe Starship HLS as the lander for that mission, but the agency has not publicly tied a specific Starship test flight number to a firm Artemis launch date. The schedule depends on technical readiness, regulatory approvals, and congressional funding cycles, three variables that rarely align on command.Blue Origin’s separate Human Landing System contract for Artemis V adds competitive pressure but does not change the fundamental requirement for Starship: NASA needs to see orbital refueling work before it commits crew to a mission that depends on it. The agency’s risk tolerance for human spaceflight is shaped by decades of hard lessons, from Challenger to Columbia, and no amount of schedule pressure is likely to shortcut the demonstration campaign.
What NASA has made clear, through its published mission architecture, is that the depot-and-tanker chain is not a stretch goal. It is the baseline design. If orbital refueling proves unreliable, the agency would need to either redesign the lander or adopt an entirely different vehicle, either of which would add years to an already delayed program.
Three actors, three timelines
The real tension in this story sits at the intersection of three organizations operating under different constraints. SpaceX wants to iterate fast, flying as often as possible to retire technical risk through rapid testing. NASA needs those tests to succeed in a specific sequence before it can certify Starship HLS for crew. And the FAA must clear each flight through an environmental review process that was not designed for the cadence SpaceX prefers.Each actor controls a piece of the timeline, and none controls all of it. SpaceX cannot fly without FAA clearance. NASA cannot schedule a crewed landing without verified refueling data. The FAA cannot accelerate reviews without compromising the environmental and safety analysis Congress requires it to perform.
For anyone tracking the Artemis program or the commercial launch industry, the practical guidance is straightforward: watch the FAA’s Boca Chica portal for new tiered assessments tied to upcoming flights, monitor NASA’s mission overviews for updates to the depot-and-tanker architecture, and treat any detailed Flight 12 scenario as provisional until backed by official documentation. The outlines of the lunar landing system are visible in the evidence that exists today. The exact role Flight 12 will play in that story depends on tests yet to fly and approvals yet to be signed.
The issue is the tank that is to receive the fuel / oxidizer is empty or low in internal pressure.
The first of the loads are at the same time being moved and as its move will drop as it exits and begin boiloff and as time goes that internal pressure of boiloff will need venting while still pumping more into the rising pressure and filling. The boil off will also happen as the tank is emptied which may allow the increasing pressure to aid in the push but at some point internal pressure will drop to the equal level of the other tank and will no longer be able to transfer any additional amount.
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SpaceX uses the boil-off vapors as the tank pressurants, and manages it to desired tank pressure levels by deliberate controlled venting. In addition, they use it for cold-gas attitude thrusters as well.
What they did in the tank-tank test inside the one vehicle, was use the cold gas thrusters to create ullage thrust. And that ullage thrust provides the slight acceleration needed to settle the propellants into the aft tank bottoms, where the pumps can draw a suction on liquid without vapor spaces in it. That ullage thrust also slightly alters the orbital path, so you CANNOT do it that way at a space station.
But it could be done with two vehicles firmly docked together. Which is how they plan to do it, refueling one Starship docked to the other. The acceleration is slight, so you must provide ullage thrust for some period of time (minutes?) before the propellants settle, and continue to provide it all during the pumping operation. It will alter the orbit of the docked pair of vehicles.
GW
Last edited by GW Johnson (2026-04-24 09:00:51)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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