A crew of two astronauts will transfer from Orion to HLS, which will then descend to the lunar surface for a stay of approximately 7 days, including at least five EVAs.

The concept of operations for a single lunar human landing mission will involve all three ship variants, as well as docking with another NASA-supplied spacecraft in near-rectilinear halo orbit (NRHO) nearer the Moon.

[6] NASA added this will also allow SpaceX to accelerate vehicle builds to help ensure availability and on time delivery for mission integration.

[14] As of 2024[update], NASA expects that SpaceX will begin a propellant transfer test campaign in approximately March 2025, and complete it during summer 2025.

[19] The launches will need to be in rapid succession in order to maintain schedule constraints and limit the loss of liquid cryogenic propellants due to boiloff.

[23][24] In the early 2010s, NASA originally planned to use the Orion spacecraft and the Space Launch System (SLS) to land astronauts on the Moon.

[25] The SLS is a launch vehicle NASA developed as replacement for the Space Shuttle following its retirement in 2011, and to bolster Shuttle-related jobs that would otherwise have been lost.

[31] To address these challenges, NASA issued a request for proposals to commercial companies to develop a Human Landing System (HLS) in 2018.

[36][21] Starship HLS was first made public when it was initially selected by NASA in April 2020 for a design study as part of their Artemis program, which aims to land humans on the Moon.

SpaceX was one of three teams selected to develop competing lunar lander designs for the Artemis program over a year-long[37] period starting in May 2020.

[21] On 26 April 2021, Blue Origin and Dynetics separately filed formal protests of the award to SpaceX at the US Government Accountability Office (GAO).

[44] On 13 August 2021,[45] Blue Origin filed a lawsuit in the US Court of Federal Claims challenging "NASA's unlawful and improper evaluation of proposals".

[48][49][50] On 4 November 2021, the court granted the federal government's motion to dismiss the case,[51][52][53] and NASA announced that it would resume work with SpaceX as soon as possible.

[58] The head of NASA's moon and Mars exploration strategy said that the delay of Artemis III from 2025 to 2026 was partly due to "development challenges" with their contractors (SpaceX and Lockheed Martin).

[59] In November 2023 the United States Government Accountability Office, in their report to Congress, outlined several challenges that the Artemis program was facing in development.

[60] The GAO noted that SpaceX had made limited progress maturing the technologies needed for in-orbit refueling and cryogenic propellant storage.

[60] The GAO concluded in their report to Congress that the Artemis III crewed lunar landing is unlikely to occur in 2025, and that a launch date in early 2027 is more likely.

[60][61] NASA astronauts tested the elevator concept (crew transfer between the cabin of Starship HLS and the lunar surface) in December 2023.

[62] In January 2024, NASA and SpaceX said that the uncrewed Starship HLS lunar landing and ascent test, was expected to take place in 2025, with Artemis III being delayed to no earlier than September 2026.

[65] The same month, NASA said SpaceX had accomplished over 30 HLS-specific milestones by defining and testing hardware needed for power generation, communications, guidance and navigation, propulsion, life support, and space environments protection.

[67] In a meeting of the United States House Science Subcommittee on Space and Aeronautics on 10 September 2024, Brian Babin and Haley Stevens expressed concerns that the pace of license processing under the FAA's Part 450 commercial launch and reentry regulations could impact the Artemis program since both Blue Origin and SpaceX HLS landers will launch using commercial licenses.

Kent Chojnacki, the deputy program manager for NASA's human spaceflight office, said the contract structure is different and "two completely different approaches."