NASA says SpaceX’s next Starship flight could test refueling tech
NASA’s plan to use SpaceX’s Starship for lunar missions has renewed focus on in-orbit cryogenic refueling, a capability that has never been demonstrated at scale but is critical to the Artemis architecture and long-term lunar presence. Commenters weigh the technical and programmatic risks—ranging from propellant management in microgravity and heat-shield durability to the complexity of multi-launch mission profiles—against the potential payoff of fully reusable super-heavy rockets and dramatically lower cost per kilogram to the Moon and beyond. The thread also contrasts Apollo- and Shuttle-era design philosophies with SpaceX’s aggressive test-fail-iterate approach, and questions whether current funding and safety practices can realistically support ambitions like lunar bases or eventual Mars outposts.
Artemis architecture, Starship, and lunar strategy
- Several comments contrast Apollo’s “flags and footprints” with Artemis’s goal of a sustained lunar presence.
- Some argue Apollo was a technological dead end; others say an incremental path (reusable Saturn derivatives, NERVA, reusable landers, Apollo Applications Program) was possible but politically defunded.
- Near Rectilinear Halo Orbit (NRHO) and Gateway are criticized as complex and schedule‑constraining; defenders note current constraints of SLS/Orion and future Starship performance are driving architecture.
- There is debate over whether many Starship tanker launches per mission are practical; supporters say full reusability and high cadence make it viable, critics call Mars colonization claims unrealistic and marketing‑driven.
In‑orbit cryogenic refueling challenges
- NASA’s $53M “tipping point” demo for transferring ~10 tons of LOX between Starship tanks is discussed as a key HLS milestone.
- Core technical issues: propellant “ullage” in microgravity, slosh dynamics, keeping liquid near intakes, pressurization, and chilling receiving tanks to avoid boil‑off.
- Proposed solutions mentioned: milli‑g settling via thrusters, possible spinning of vehicles, propellant management devices, internal circulation schemes. Some say SpaceX already has relevant experience from upper‑stage relights; others stress large‑scale transfer is unproven.
Test flights, explosions, and methodology
- Strong disagreement over whether recent Starship flights are “successes.”
- One side: these are test flights with many objectives; partial success (pad survival, full engine performance, hot‑staging, separation) is valuable, and hardware is intentionally expendable.
- Other side: if key objectives aren’t met (reach orbit, test heat shield, refueling), the flight is a failure; praising explosions is seen as spin.
- Comparisons made to Saturn/Apollo testing: those programs also had serious failures and “failed successfully” tests, but with vastly larger budgets and different risk posture.
Heat shields and reusability
- Extended argument over whether Starship’s ceramic tiles are “ablative.” Consensus in thread: they are reusable thermal protection, not designed to ablate like Dragon’s PICA shield.
- Tiles differ from Shuttle’s: pinned to a steel structure, mostly uniform, not individually shaped and glued, theoretically more robust—but durability and rapid reuse remain open questions.
Economics and funding
- Rough back‑of‑envelope cost estimates for Super Heavy/Starship stages are discussed; wide uncertainty remains, but consensus is they are far cheaper than Saturn‑class or SLS hardware on a per‑kg basis.
- Some note SpaceX spends on the order of billions per year on Starship yet remains overall profitable, largely due to Falcon 9 and Starlink.