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Artemis II Moon Mission
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NASA Cancels SLS Upgrades and Delays First Landing

2 min read
15:01UTC

Administrator Isaacman cut the Block 1B and Block 2 variants in February, pushing the first crewed lunar landing to Artemis IV in 2028.

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ScienceDeveloping
Key takeaway

SLS is now a five-mission bridge technology being phased out by the agency that operates it.

On 26 February 2026, NASA Administrator Jared Isaacman cancelled the Block 1B and Block 2 upgrades to the Space Launch System, standardising the programme on the current Block 1 configuration 1. These were the variants designed to carry crew and cargo to the Moon simultaneously. Years of development spending on them is now written off.

Artemis III, originally planned as the first crewed lunar landing since 1972, has been redesignated as a low Earth orbit lander test 2. The first potential crewed landing now falls to Artemis IV, targeting 2028. The programme has slipped five to seven years from its original projections.

The restructuring narrows SLS to a five-mission bridge. After Artemis V, NASA plans to transition to commercial vehicles. The rocket Congress mandated and funded is being phased out by the agency flying it.

Deep Analysis

In plain English

The SLS rocket that launched yesterday was built to a standard version. There were plans to build more powerful upgraded versions for future, more ambitious missions. NASA has now cancelled those upgrades. This means the same basic rocket that flew yesterday will fly the next four missions, and then NASA plans to retire it in favour of commercial rockets from private companies. The mission that was supposed to land humans on the Moon has been downgraded to a test in orbit near Earth. The actual landing is now planned for the mission after that, in 2028 at the earliest.

Deep Analysis
Root Causes

Block 1B was designed to fly the co-manifest configuration, carrying both crew and cargo to the Moon simultaneously. The requirement drove a more powerful upper stage and structural modifications that added cost without improving Block 1 performance on the crew-only missions that comprise most of the Artemis manifest.

The cancellation reflects the Isaacman administration's preference for a commercial-centric architecture in which the SLS serves as a bridge rather than a permanent system. This preference is consistent with Isaacman's background as founder of Shift4 Payments and a SpaceX crew mission commander, but it creates a structural question: the commercial vehicles intended to replace SLS have not yet been selected or qualified for crewed lunar missions.

Sources:SpaceNews
Mentions:NASA →Jared Isaacman →Space Launch System →Artemis III →Artemis IV →Orion →Artemis I →SLS Block 1B →SLS Block 2 →Artemis II →Prima →Interim Cryogenic Propulsion Stage →
First Reported In

Update #1 · Artemis II Commits to the Moon With Three Open Questions

SpaceNews· 2 Apr 2026
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Causes and effects
This Event
NASA Cancels SLS Upgrades and Delays First Landing
Years of SLS upgrade development have been written off, and the mission planned as the first crewed landing has been redesignated as a low Earth orbit test.
Led to
Canada's Silence on Gateway Persists Into Orbit
Isaacman's post-TLI statement is a domestic political consequence of his earlier cancellation of SLS upgrades and Artemis III redesignation.
Occurred 3 Apr 2026
Read story →
White House guts NASA science by 47%
Isaacman's cancellation of SLS Block 1B/2 upgrades (ID:1892) is consistent with and reinforced by the FY2027 proposal's Artemis-first framing (event 2).
Occurred 3 Apr 2026
Read story →
Different Perspectives
ESA
ESA
The European Service Module has operated without anomaly for five consecutive days, with the OMS-E engine's translunar injection precision directly responsible for eliminating both correction burns. ESA's hardware contribution is the mission's highest-performing subsystem.
NASA
NASA
NASA cancelled a second consecutive outbound correction burn and confirmed Orion in lunar gravitational dominance, while declining to publish any crew radiation dose data through a complete G3 storm cycle. Bipartisan congressional rejection of its $18.8 billion FY2027 budget proposal means the agency faces a political fight even as its spacecraft performs above expectations.
Dual-framework nations
Dual-framework nations
Signing both the Artemis Accords and the ILRS framework is rational hedging, not defection; smaller nations maximise access without exclusive commitment. Lunar governance is genuinely multipolar, and the US coalition count of 61 overstates exclusivity.
Boeing / Northrop Grumman
Boeing / Northrop Grumman
SLS component production spans more than 40 US states, giving the industrial base strong political protection regardless of commercial alternatives. Congressional mandates guarantee contracts through FY2029, insulating the supply chain from technical programme changes.
NASA Office of Inspector General
NASA Office of Inspector General
The IRB heat shield findings should have been published before launch. The Starship HLS is two years behind schedule with a worsening manual control dispute. NASA has no crew rescue capability for lunar surface operations. The programme is proceeding with documented, unresolved risks.
SpaceX
SpaceX
Starship HLS development is ongoing. SpaceX disputes the characterisation of the manual crew control requirement as unresolved, maintaining its autonomous landing architecture meets mission safety objectives. The company has not publicly responded to the OIG's worsening-trend characterisation.