SpaceX Starship HLS Viability for Artemis IV (2028): A Critical Assessment

Executive Summary

• Orbital propellant transfer demonstration remains unproven. As of April 24, 2026, the two-ship cryogenic propellant transfer demonstration targeted for June 2026 has not occurred; only a limited intra-vehicle header-tank transfer was achieved on IFT-3 in March 2024. The Critical Design Review for the propellant transfer system had not been completed as of March 2026, and the demonstration has slipped approximately 14 months from its original March 2025 target [1, 2].

• The NPR 8705.2C manual control dispute is unresolved. NASA's human-rating requirements mandate crew manual control of flight path and attitude, but SpaceX's Starship HLS relies on a highly autonomous descent architecture. As of this date, no public resolution—whether through design modification or formal waiver—has been announced, creating a high-risk certification bottleneck for Artemis IV [3, 4].

• Starship V3 launch cadence is far short of the 10–20 tanker flights required per lunar landing. With approximately 11 total Starship flights completed through late 2025 and the first V3 vehicle (Ship 39) still in ground testing, achieving the sustained rapid-fire launch tempo needed to fill an orbital depot within a single mission window by 2028 remains a formidable challenge [1, 5].

• AxEMU–Starship HLS airlock physical compatibility has been validated at the mockup level. The June 2024 pressurized integrated test at NASA's Neutral Buoyancy Laboratory confirmed that the Axiom AxEMU suit fits through the Starship HLS airlock and elevator, but qualification testing, a planned 2027 orbital flight test, and full avionics/communications integration remain ahead [6, 7].

• Overall assessment: Starship HLS viability for an early-2028 Artemis IV landing is marginal. The NASA OIG's March 2026 report documented approximately two years of cumulative schedule delay, and the four critical-path items examined here each carry substantial residual risk. A slip of Artemis IV beyond 2028 is the most probable outcome absent rapid, sequential successes in the next 12–18 months [1].

1. Artemis IV Mission Architecture and Context

NASA's Artemis IV mission is targeted for a crewed lunar landing no earlier than early 2028 [8, 9]. Under the program restructuring announced in February 2026, the first crewed lunar surface mission was reclassified from Artemis III to Artemis IV; the revised Artemis III is now a low-Earth-orbit (LEO) test mission scheduled for 2027, designed to validate rendezvous and docking operations between the Orion spacecraft and one or both commercial landers [2, 10]. Artemis IV will launch four astronauts aboard the Space Launch System (SLS) in the Orion capsule; two crew members will descend to the lunar surface aboard the Starship HLS (or, potentially, Blue Origin's Blue Moon lander), conduct approximately one week of surface operations, and return to lunar orbit while the remaining two crew members stay aboard Orion [9, 11].

The SpaceX Starship HLS contract, originally valued at $2.89 billion in April 2021 and subsequently revised to approximately $4 billion, requires SpaceX to demonstrate orbital refueling, crew safety features, and integration with NASA crew systems before the crewed landing [1, 12]. The NASA Office of Inspector General (OIG) report IG-26-004, released in March 2026, documented approximately two years of schedule delays relative to initial contract expectations and flagged multiple unresolved technical risks [1]. The report noted that the uncrewed demonstration mission, originally planned for 2025, has been pushed to 2027 [1].

This analysis evaluates four critical-path elements that will determine whether Starship HLS can credibly support an early-2028 landing.

2. Orbital Propellant Transfer Demonstration and Boil-Off Characterization

2.1 Demonstration Architecture

The Starship propellant transfer demonstration is designed to prove the essential capability of refueling a Starship vehicle in low Earth orbit—a prerequisite for any lunar mission, since Starship HLS must receive approximately 1,200–1,500 metric tons of liquid oxygen and liquid methane before performing its trans-lunar injection burn [12, 13]. The planned demonstration involves two Starship launches within a three-to-four-week interval. The first vehicle will be placed into orbit to serve as a depot, while the first-stage booster returns to the launch site for tower capture. A second "tanker" Starship will then launch, perform autonomous rendezvous and docking, and transfer cryogenic propellant via liquid oxygen transfer lines exploiting a pressure differential between the two vehicles. After transfer, the tanker will undock, reenter, and be caught by the launch tower, while the depot remains in orbit [13, 2].

2.2 Current Status

As of April 24, 2026, the two-ship orbital propellant transfer demonstration has not occurred [2, 1]. SpaceX's October 30, 2025 corporate update stated that both the long-duration orbital flight test and the ship-to-ship transfer test were targeted for 2026 [14]. The current target date is June 2026—approximately ten weeks from today—and one report suggests the two-ship transfer demonstration may be Flight 14 or later in the Starship flight sequence, though this has not been confirmed by NASA or SpaceX [15]. The June 2026 demonstration is explicitly framed as serving the co-equal objective of characterizing long-duration storage viability, not only transfer mechanics [2].

The only in-space propellant handling milestone achieved to date is a partial header-tank transfer demonstrated during Starship Integrated Flight Test 3 (IFT-3) in March 2024, which NASA characterized as a successful "tipping-point" fluid-transfer test within a single vehicle [8, 13]. Full main-tank ship-to-ship transfer between two separate vehicles remains entirely unproven.

The OIG report IG-26-004 noted that the flight test campaign for ship-to-ship propellant transfer was originally slated to begin around March 2025 and that the associated Critical Design Review had not been completed as of March 2026 [1]. This represents a slip of more than a year from the original schedule, and the absence of a completed CDR raises questions about the maturity of the transfer system's detailed design.

2.3 Boil-Off Characterization

The long-duration orbital flight test, which is planned to precede the transfer demonstration by several weeks, is specifically designed to characterize propellant boil-off rates and collect data on propulsion and thermal behavior in the space environment [8, 13]. This is a critical unknown: without active thermal management or passive insulation, boil-off losses are estimated at approximately 77 tons of propellant per day in near-Earth orbit—roughly 0.5% of total propellant mass per day for a baseline Starship [16]. The magnitude of boil-off directly determines how many tanker flights are needed per mission and how quickly the refueling campaign must be executed.

SpaceX has introduced significant insulation and vacuum-jacketed plumbing on the Starship Block 2 vehicle (designated S33), which was the first to incorporate these thermal management features [13]. Multi-layer insulation can theoretically reduce heat flow by up to 99 percent compared to uninsulated tanks [13]. Active cooling systems using regenerative heat exchangers are also under consideration and could, in principle, reduce boil-off to less than one ton per day during lunar transit phases [13]. However, none of these systems have been validated in orbit. The June 2026 long-duration test will provide the first empirical data on actual boil-off rates, and the results will have cascading implications for the entire tanker-flight architecture.

2.4 Risk Assessment

The propellant transfer demonstration is the single highest-risk item on the Artemis IV critical path. If the June 2026 target slips—or if the demonstration reveals unexpectedly high boil-off rates or transfer inefficiencies—the downstream schedule for the uncrewed HLS demonstration (now targeted for 2027) and the crewed Artemis IV landing (early 2028) will compress to the point of infeasibility. The OIG's finding that the CDR was incomplete as of March 2026 suggests that the June target carries meaningful schedule risk [1].

3. NPR 8705.2C Manual Control Requirements Dispute

3.1 The Regulatory Framework

NASA Procedural Requirements document NPR 8705.2C, titled "Human-Rating Requirements for Space Systems," has been effective since July 10, 2017, and is set to expire December 16, 2028 [3, 17]. The document establishes the baseline safety and design requirements for any spacecraft that carries NASA crew. Among its provisions, NPR 8705.2C mandates that crew members must have the capability to manually control the vehicle's flight path and attitude [3, 4]. The document defers certain implementation specifics to the companion standard NASA-STD-8719.29 and prioritizes human utilization as a layer of failure tolerance [3].

The Artemis HLS fixed-price contract incorporates the NPR 8705.2C manual control clause as a binding requirement [4].

3.2 Nature of the Dispute

SpaceX's Starship HLS is designed around a highly autonomous descent and ascent architecture, with limited direct crew control inputs during powered flight phases [12, 1]. By early 2026, a dispute had emerged between NASA and SpaceX over whether this autonomous-heavy approach satisfies the intent and letter of the manual control requirement [1, 12]. NASA's HLS program office publicly stated that there was disagreement on whether Starship's current proposed approach for landing meets the manual control requirement, and NASA does not accept SpaceX's initial design as fulfilling the crew-manual-authority intent [12]. NASA HLS manager Lisa Watson-Morgan stated in January 2025 that NASA and SpaceX are working on how to 'effectuate the crew manual control requirements' given Starship's size and automation [18]. The OIG report notes that NASA's tracking of SpaceX's manual control risk indicates a 'worsening trend' [1]. Contextually, during Apollo's six crewed lunar landings, astronauts engaged backup manual control methods during every single landing, a historical precedent NASA cites to justify the requirement [1]; the Starship HLS stands approximately 50–55 meters tall on the lunar surface, making traditional manual control architecturally challenging [1].

SpaceX has argued that its simplified, autonomous architecture improves overall safety by reducing the potential for human error during the complex powered-descent phase [1]. NASA, however, insists that the regulatory framework requires meaningful crew override capability as a fundamental layer of redundancy [3, 4].

3.3 Resolution Status

As of April 24, 2026, no public resolution of the dispute has been announced [12, 1]. NASA and SpaceX have been engaged in ongoing technical discussions, including "crew office hours" sessions involving astronauts and SpaceX engineers, to explore how the manual control requirements might be effectuated within Starship's architecture [6, 12]. However, the OIG's March 2026 report flagged this as a continuing crew safety concern [1].

The dispute presents two possible resolution paths, each with significant implications:

1. Design modification: SpaceX could add manual flight control interfaces (e.g., hand controllers, direct thruster command authority) to the Starship HLS cockpit. This would require substantial redesign, additional testing, and potential mass and complexity penalties.

2. Formal waiver: NASA could grant a waiver or tailored interpretation of NPR 8705.2C that accepts a "supervisory override" model rather than full manual stick-and-rudder control. NPR 8705.2C remains binding until formally waived [4], and any waiver would require rigorous safety justification and acceptance of residual risk at the highest levels of NASA leadership.

Neither path is quick. A design modification would add months of development and verification. A waiver process, while potentially faster, would expose NASA to significant political and safety-culture risk, particularly given the OIG's public concerns. A potential resolution model is the Dragon crew agreement precedent, in which manual control was implemented via touchscreen-based interfaces providing crew authority without requiring traditional joystick architecture [1]. The Starship HLS Critical Design Review has been pushed to August 2026, slipping from its original late-summer 2025 target [1]. This dispute is a high-risk certification bottleneck that could independently delay Artemis IV regardless of progress on other technical fronts.

4. Starship V3 Launch Cadence vs. Required Tanker Flights

4.1 Tanker Flight Requirements

The number of tanker launches required to fill the Starship HLS orbital depot is one of the most consequential—and most debated—parameters in the Artemis architecture. NASA has estimated that a single lunar landing mission requires roughly 10 to 20 tanker launches for LEO refueling, delivering up to approximately 1,500 metric tons of LOX/CH4 [12, 19, 20]. The wide range reflects uncertainty about boil-off losses, transfer efficiency, and the payload capacity of the tanker variant.

The following table summarizes the range of estimates from various sources:

The actual number will not be known until the June 2026 boil-off characterization test provides empirical data. If boil-off rates are higher than modeled, the tanker count could push toward the upper end of the range, compounding the launch cadence challenge.

4.2 Current Starship Flight History and V3 Status

Through approximately October 2025, SpaceX had completed 11 Starship integrated flight tests. Sources characterize roughly 6 of these as fully successful, with the remainder achieving partial objectives or experiencing anomalies during various flight phases [8, 14]. This flight rate—approximately 11 flights over 30 months—translates to roughly one flight every 2.7 months, far below the cadence needed for a tanker campaign.

The Starship Version 3 (V3) represents a significant upgrade intended to increase payload capacity to over 100 metric tons to LEO and improve reusability [5, 13]. The first V3 prototype, Ship 39, has undergone ground-based cryogenic system tests and static fire testing [5, 23]. Starship Flight 12, which will incorporate the first V3 elements, is targeting late April or early May 2026 from Starbase Pad 2 [5], having slipped from an original March 2026 target—a delay of approximately eight weeks [5]. As of April 24, 2026, Flight 12 has not yet occurred. V3 static fires and Booster 19 static fires were ongoing in April 2026 [5, 14].

4.3 Cadence Projections and Infrastructure

Projections for 2026 Starship launch cadence range from 7 to 12 flights if V3 proves reliable [14, 1]; NASA reported SpaceX aimed for as many as 25 Starship missions per year on its 2025 roadmap [18]. This is far below the 10–20 tanker flights needed for even a single Artemis IV refueling campaign. The OIG report specifically notes that the required launch pad turnaround cadence is 12 to 24 days and that SpaceX has not yet demonstrated this tempo [1]. Furthermore, if each tanker launch carries a non-trivial failure risk, the probability of completing 14 or more consecutive successful refueling launches within a narrow window is statistically daunting without a leap in operational reliability [1]. Florida Pad LC-39A activation is targeted no earlier than late 2026 [24], and SpaceX has announced intentions to ultimately achieve one launch per hour within approximately 4–5 years [14].

SpaceX's longer-term infrastructure plans are ambitious. The FAA's environmental impact assessments have cleared up to 76 Starship launches per year from Space Launch Complex 37 (SLC-37) and up to 44 per year from Launch Complex 39A (LC-39A) at Kennedy Space Center [25, 26]. SpaceX has publicly targeted approximately 40 launches per year from LC-39A by around 2027 and has discussed infrastructure for up to 120+ Starship launches per year across multiple pads (three in Florida, two in Texas) [26, 25]. If SpaceX were to achieve weekly launches from Florida by 2027, the 10+ tanker requirement per mission would become theoretically feasible.

However, the gap between regulatory clearance and operational reality is vast. No launch provider has ever sustained the kind of rapid-cadence campaign envisioned here for a vehicle of Starship's size and complexity. Two Artemis landings in 2028 would require approximately 22 tanker flights that year in addition to the HLS vehicles themselves, the uncrewed demo, and any commercial payloads—a total Starship manifest that would demand a launch rate never before achieved.

4.4 Cadence Risk Summary

The launch cadence requirement is arguably the most structurally challenging element of the Starship HLS architecture. Even with optimistic assumptions about V3 reliability and pad turnaround times, achieving the necessary tempo by early 2028 would require an unprecedented acceleration from the current flight rate.

5. Axiom AxEMU Spacesuit Interface Compatibility with Starship HLS Airlock

5.1 The AxEMU Program

The Axiom Extravehicular Mobility Unit (AxEMU) is the designated spacesuit for Artemis lunar surface operations [7, 6]. Developed by Axiom Space with support from KBR, the AxEMU must interface with the Starship HLS airlock and elevator systems to enable crew egress and ingress during lunar surface EVAs. The suit must also communicate with various Artemis systems, including the HLS avionics and environmental controls [7, 6].

5.2 June 2024 Integrated Test

An initial water test at the Neutral Buoyancy Laboratory occurred in April 2024 [27], followed by the first pressurized integrated test on June 4, 2024—the first such test since the Apollo era [6, 28]. That June test involved astronauts Peggy Whitson of Axiom Space and NASA astronaut Doug Wheelock [28] in prototype AxEMU suits entering a full-scale mockup of the Starship HLS airlock and elevator at SpaceX's Hawthorne facility; the test rig was positioned immediately outside the HLS airlock and supplied breathing air, power, and cooling as would occur in flight [28]. The test rig pressurized the suits and supplied breathing air, power, and cooling as would occur in flight [6, 28].

Key outcomes of the approximately three-hour test included:

• Physical compatibility confirmed: The AxEMU suits and their Portable Life Support Systems (PLSS) fit through the Starship airlock and cabin volume [6, 28].
• Dual-suit operations validated: The test included dual-suit runs, confirming that two suited crew members can operate simultaneously in the airlock [6, 28].
• Lunar gravity simulation: Testing was conducted under simulated 1/6g conditions [6].
• Mobility and flexibility feedback: Engineers collected data on suit flexibility, agility, and the layout, physical design, mechanical assemblies, and clearances inside the HLS [28].

No airlock compatibility issues were reported from this test [6, 28]. The Starship HLS design incorporates dual airlocks in which suits are stored, a configuration intended to mitigate lunar regolith contamination of the cabin [6].

5.3 Remaining Milestones

Despite the encouraging mockup-level results, significant work remains before the AxEMU is certified for flight:

• Design maturity: As of mid-2024, Axiom reported that the AxEMU had passed its Preliminary Design Review and was entering Critical Design Review (CDR) [28, 7]. The transition from CDR to qualification testing is a major step.

• Qualification testing: Axiom is moving through final design and qualification testing phases, which simulate lunar conditions and launch loads [7, 6]. This testing is essential for final certification.

• Orbital flight test: Axiom is targeting a 2027 orbital flight test of the AxEMU, which would be the first in-space validation of the suit [29, 30]. This test is a prerequisite for lunar surface certification.

• Avionics and communications integration: According to the NASA OIG, the new Artemis suits need to communicate with various Artemis systems, including the Human Landing System contracted to SpaceX [31], which suggests the AxEMU would need to interface with Starship's avionics and airlock control systems for telemetry, life support monitoring, and EVA management. While the physical fit has been confirmed, the specific electronic and software integration layers have not been publicly demonstrated.

• Schedule risk: The NASA OIG has flagged spacesuit development delays as a potential impact to the Artemis timeline [31], and specifically noted that the new Artemis suits need to communicate with various Artemis systems, including the Human Landing System contracted to SpaceX, as a distinct integration requirement [31]. The OIG concluded that if Axiom's testing schedule follows historical averages for spacesuit qualification, demonstrations would not occur until 2031 [31]. Notably, Collins Aerospace and NASA mutually agreed to descope Collins' xEVAS task orders in 2024 due to inability to meet the agreed-upon schedule, leaving NASA reliant solely on Axiom Space under the xEVAS contracts originally valued at up to $3.1 billion [31]. NASA acting administrator Jared Isaacman has expressed confidence that AxEMU will be ready and indicated intent to 'get the spacesuits ready sooner' [32], and Axiom has stated it is actively engaged with NASA to get the suit ready for a 2028 landing [32]. The margin between the 2027 flight test and an early-2028 landing remains thin.

Axiom has expressed confidence that the suits will be ready for the Artemis mission timeline [7, 28]. However, the compressed schedule between a 2027 flight test and an early-2028 crewed lunar landing leaves minimal margin for any qualification failures or design iterations.

6. Integrated Viability Assessment

6.1 Critical Path Dependencies

The four elements examined in this report are not independent risks—they form an interconnected critical path with cascading dependencies:

1. Propellant transfer → Tanker count: The boil-off data from the June 2026 test will determine the actual number of tanker flights required. Higher-than-expected boil-off pushes the tanker count upward, which in turn demands a higher launch cadence.

2. Launch cadence → Mission window: Even if the propellant transfer technology works, SpaceX must demonstrate the ability to launch 10–20 tankers within a compressed window (likely 2–4 weeks to minimize cumulative boil-off losses). This requires not just annual launch rate but rapid sequential turnaround.

3. Manual control resolution → Certification: The NPR 8705.2C dispute must be resolved before NASA can certify Starship HLS for crewed flight. This is a binary gate: no resolution, no crew certification, no Artemis IV landing.

4. AxEMU qualification → Surface operations: Even if Starship HLS is ready, the mission cannot proceed without certified spacesuits. The 2027 flight test is the last major milestone before the suits must be declared flight-ready.

6.2 Schedule Margin Analysis

The NASA OIG report IG-26-004 documented approximately two years of cumulative schedule delay on the Starship HLS contract [1], with approximately 20% of contractual milestones complete (49 of the total) as of October 2025 [14]. The OIG also found that the planned uncrewed HLS demonstration will not be fully representative of the crewed vehicle configuration—it will lack life support systems, the crew airlock with controls, and the elevator mechanism [1]. Additionally, NASA evaluated rescue options for crew stranded on the lunar surface and determined the cost would be prohibitive; no rescue capability exists for early crewed Artemis missions [1]. With the Artemis program restructuring pushing the first landing to Artemis IV in early 2028, the effective schedule has been partially reset—but the technical milestones have not been correspondingly accelerated.

The remaining schedule from April 2026 to an early-2028 landing requires the following sequence to execute without significant delays:

The margin on virtually every milestone is thin to nonexistent. A single significant delay in any of the 2026 milestones would likely cascade into the 2027 demonstration schedule, which in turn would push Artemis IV beyond early 2028.

6.3 Probability Assessment

Based on the evidence reviewed in this report, one analytical assessment places the probability of Starship HLS being ready for an early-2028 Artemis IV crewed lunar landing at roughly 40–50 percent, though this reflects editorial judgment rather than any published official or independent estimate. This assessment reflects:

• The propellant transfer demonstration has not occurred and the CDR was incomplete as of March 2026.
• The manual control dispute has no announced resolution path.
• V3 has zero flight heritage and the launch cadence must increase by an order of magnitude.
• The AxEMU is on a parallel but equally compressed timeline.

NASA has built some programmatic resilience into the architecture. The revised Artemis III LEO demonstration in 2027 provides an intermediate validation opportunity. The "Option B" architecture flexibility allows NASA to potentially use Blue Origin's Blue Moon lander as an alternative or complement to Starship HLS [12, 8]. In October 2025, then-interim NASA Administrator Sean Duffy announced the Artemis IV lander contract would be opened to additional providers beyond SpaceX, citing concerns that Starship was 'behind' on HLS development [33, 22]; Blue Origin subsequently paused its suborbital New Shepard program to focus resources on the competitive lunar lander opportunity [33]. The CSIS analysis of the Artemis program has characterized the overall approach as carrying significant schedule risk but noted that the phased restructuring provides some buffer [34]. Providing a positive program data point, the Artemis II mission successfully completed with splashdown off the coast of San Diego on April 10, 2026, with the Orion thermal protection system performing as expected with significantly reduced char loss compared to Artemis I [10].

6.4 Conclusion

Starship HLS remains a viable but high-risk element of the Artemis IV architecture. The technology is not fundamentally infeasible—orbital propellant transfer, rapid launch cadence, and autonomous precision landing are all within the realm of engineering possibility. The question is whether they can be demonstrated, validated, and certified within the approximately 21 months remaining before an early-2028 landing.

The most likely outcome, given current evidence, is that Artemis IV will slip beyond early 2028. The June 2026 propellant transfer demonstration is the near-term inflection point: a successful demonstration would substantially de-risk the program and validate the core architecture, while a failure or significant delay would almost certainly push the crewed landing into 2029 or later. The resolution of the NPR 8705.2C manual control dispute and the AxEMU qualification timeline represent additional independent risk factors that could each independently delay the mission even if the propellant transfer succeeds.

Stakeholders should monitor three near-term indicators over the next 60–90 days: (1) whether Flight 12 successfully flies the first V3 elements, (2) whether the propellant transfer CDR is completed, and (3) whether any public announcement is made regarding the manual control dispute resolution. The trajectory of these three items by mid-summer 2026 will provide the clearest signal yet of whether an early-2028 Artemis IV landing remains achievable.

References

[1] Final report ig 26 004 nasas management of the human landing system contracts (oig.nasa.gov). oig.nasa.gov. https://oig.nasa.gov/wp-content/uploads/2026/03/final-report-ig-26-004-nasas-management-of-the-human-landing-system-contracts.pdf

[2] 1 going back to the moon (nasa.gov). nasa.gov. https://nasa.gov/wp-content/uploads/2026/03/1-going-back-to-the-moon.pdf?emrc=69c53c728f058

[3] N PR 8705 002C (nodis3.gsfc.nasa.gov). nodis3.gsfc.nasa.gov. https://nodis3.gsfc.nasa.gov/npg_img/N_PR_8705_002C_/N_PR_8705_002C_.pdf

[4] NPR 8705.2C - main. nodis3.gsfc.nasa.gov. https://nodis3.gsfc.nasa.gov/displayDir.cfm?c=8705&s=2C&t=NPR

[5] Spacex fires up next gen version 3 starship ahead of landmark may test flight photos (space.com). space.com. https://space.com/space-exploration/launches-spacecraft/spacex-fires-up-next-gen-version-3-starship-ahead-of-landmark-may-test-flight-photos

[6] Nasa astronauts practice next giant leap for artemis (nasa.gov). nasa.gov. https://nasa.gov/directorates/esdmd/artemis-campaign-development-division/human-landing-system-program/nasa-astronauts-practice-next-giant-leap-for-artemis

[7] NASA Moon Mission Spacesuit Nears Milestone. nasa.gov. https://nasa.gov/humans-in-space/nasa-moon-mission-spacesuit-nears-milestone

[8] Artemis (nasa.gov). nasa.gov. https://nasa.gov/humans-in-space/artemis

[9] Artemis IV - NASA. nasa.gov. https://nasa.gov/mission/artemis-iv

[10] NASA on Track for Future Missions with Initial Artemis II Assessments. nasa.gov. https://nasa.gov/missions/nasa-on-track-for-future-missions-with-initial-artemis-ii-assessments

[11] Artemis III - NASA. nasa.gov. https://nasa.gov/mission/artemis-iii

[12] Human Landing Systems - NASA. nasa.gov. https://nasa.gov/reference/human-landing-systems-2

[13] Techup 2024 web 120924 (nasa.gov). nasa.gov. https://nasa.gov/wp-content/uploads/2023/05/techup-2024-web-120924.pdf?emrc=69093aa383dc3

[14] Updates (spacex.com). spacex.com. https://spacex.com/updates

[15] NASA Updates on Starship Refueling, as SpaceX Prepares Flight 4 of Starship - NASASpaceFlight.com. nasaspaceflight.com. https://nasaspaceflight.com/2024/04/nasa-hls-update

[16] Long duration propellant stability in Starship - Casey Handmer's blog. caseyhandmer.wordpress.com. https://caseyhandmer.wordpress.com/2025/03/14/long-duration-propellant-stability-in-starship

[17] DisplayDir.cfm (nodis3.gsfc.nasa.gov). nodis3.gsfc.nasa.gov. https://nodis3.gsfc.nasa.gov/displayDir.cfm?Internal_ID=N_PR_8705_002C_&page_name=Preface

[18] Here’s what NASA would like to see SpaceX accomplish with Starship this year - Ars Technica. arstechnica.com. https://arstechnica.com/space/2025/01/heres-what-nasa-would-like-to-see-spacex-accomplish-with-starship-this-year

[19] Starship lunar lander missions to require nearly 20 launches nasa says (spacenews.com). spacenews.com. https://spacenews.com/starship-lunar-lander-missions-to-require-nearly-20-launches-nasa-says

[20] At least 15 starship launches to execute artemis iii lunar landing (spacepolicyonline.com). spacepolicyonline.com. https://spacepolicyonline.com/news/at-least-15-starship-launches-to-execute-artemis-iii-lunar-landing

[21] Status (x.com). x.com. https://x.com/i/status/1810727898631819514

[22] Musk Stumbles on the Way to the Moon. time.com. https://time.com/7328257/musk-duffy-feud-nasa-spacex

[23] SpaceX's Ship 39 is so cool in Starship V3 test | Space photo of the day for March 9, 2026. space.com. https://space.com/space-exploration/spacexs-ship-39-is-so-cool-in-starship-v3-test-space-photo-of-the-day-for-march-9-2026

[24] Status (x.com). x.com. https://x.com/i/status/2047370127776051278

[25] SpaceX SSH LC 39A Final EIS Volume II AppB2 Essential Fish Habitat Assessment NMFS (faa.gov). faa.gov. https://faa.gov/space/stakeholder_engagement/spacex_starship_ksc/%20SpaceX-SSH-LC-39A-Final-EIS-Volume-II-AppB2-Essential-Fish-Habitat-Assessment-NMFS.pdf

[26] SpaceX Starship Super Heavy Project at the Boca Chica Launch Site. faa.gov. https://faa.gov/space/stakeholder_engagement/spacex_starship

[27] Kbr and axiom space successfully test next generation spacesuit critical step toward returning moon (kbr.com). kbr.com. https://kbr.com/en/insights-news/press-release/kbr-and-axiom-space-successfully-test-next-generation-spacesuit-critical-step-toward-returning-moon

[28] First artemis iii integrated test complete (axiomspace.com). axiomspace.com. https://axiomspace.com/news/first-artemis-iii-integrated-test-complete

[29] Axiom space plans 2027 flight test of spacesuit (spacenews.com). spacenews.com. https://spacenews.com/axiom-space-plans-2027-flight-test-of-spacesuit

[30] Axiom space is ready to test its next generation spacesuit in 2027 2000746723 (gizmodo.com). gizmodo.com. https://gizmodo.com/axiom-space-is-ready-to-test-its-next-generation-spacesuit-in-2027-2000746723

[31] Spacesuit Development Delays Could Impact Artemis Timeline and .... oig.nasa.gov. https://oig.nasa.gov/news/spacesuit-development-delays-could-impact-artemis-timeline-and-iss-operations

[32] NASA still confident that Artemis astronauts will land on the moon in 2028 despite spacesuit delays. space.com. https://space.com/space-exploration/artemis/nasa-still-confident-that-artemis-astronauts-will-land-on-the-moon-in-2028-despite-spacesuit-delays

[33] 'Pushing this competition': SpaceX's Starship might not fly on NASA's newly revamped Artemis 3 mission. space.com. https://space.com/space-exploration/artemis/pushing-this-competition-spacexs-starship-might-not-fly-on-nasas-newly-revamped-artemis-3-mission

[34] What Comes Next for Artemis? - CSIS. csis.org. https://csis.org/analysis/what-comes-next-artemis