Hi Open Lunarians,

 

Sometime between 11 April and 22 May 2024, a chunk of rock the size of a small building slammed into the Moon's eastern limb and carved out a crater 222 metres across. Nobody noticed. It sat in the Lunar Reconnaissance Orbiter's archive for over a year until researchers comparing before-and-after images spotted it in late 2025, and two studies published on 16 September finally made it official: McGetchin crater is the largest freshly formed impact crater ever recorded in the solar system. If a natural strike that size can go unnoticed for more than a year, consider how little we know about what human operators are leaving behind. As Samuel Jardine wrote in Falling Falcons, there is still no systematic record of what has been deposited on the lunar surface, where, and by whom. The Lunar Ledger exists to build one.

 

September was a month with a focus on lunar security, and it came as the US confirmed it has weapons in orbit and the risk of escalation in space, from LEO to cislunar space, has become more evident. During the Outer Space Security Conference in Geneva, our Senior Policy Lead Samuel Jardine convened a lunar security panel and a full-room tabletop at the Geneva Centre for Security Policy, bringing Artemis Accords and ILRS signatory states to the same table, and our Fellow Aaron Mackey published on why those two blocs need shared measurement standards more than they need political alignment. You will find all of that below, alongside Lunar Ledger's presentation to the LOGIC working group.

 

Thank you for being part of this work.

 

 

Artemis Accords and ILRS missions are heading for the same south polar terrain, under different assumptions about governance and data sharing. In his third blog post, Open Lunar Fellow Aaron Mackey argues that coordination between them does not need to wait for political agreement. If the hazard models behind an operational area are published and the method for sizing it can be checked objectively based on physical constraints, an operator on either side can verify a neighbour's declaration without having to trust its intentions. Civil aviation already coordinates this way between states that disagree on much else.

 

 

In his Fellowship Showcase, Aaron Mackey walks through the Lunar Radius Framework, which sizes the area an operator can declare around its activity from the hazard it produces, whether dust, heat, or radio interference. The core operations area follows from that hazard's production rate, adjusted for how confident the operator is in its data. The harmonization buffer and coordination area scale from this, each with its own notification characteristics. An area sized this way, backed by a published reasoning chain, can be defended on technical grounds when a neighbour challenges it, and renegotiated from shared numbers when a mission changes. Watch the recording here, and read the framework here.  

 

 

On 15 September, Nhat Nguyen and Zack Gainsforth presented the Lunar Ledger to the LOGIC working group convened by Johns Hopkins APL, at a session on interoperable tools for operators. Today the Ledger registers who is operating where, and who to contact about it, with each operator owning its entries and deciding who sees what. The next layer, now in development, connects mission operations software directly to the Ledger so operators can exchange live data on their own terms. With six active objects in lunar orbit already generating frequent collision alerts and more than 400 missions planned over the next two decades, operators will need that live layer soon. Find out more at lunarledger.space.

 

 

In June, alongside the UNCOPUOS Plenary, we convened a lunar coordination scenario modeling session with the European Space Policy Institute for more than 20 delegates from Member States. Four asymmetric actors operated in one area of the south pole without agreed coordination arrangements. Declared operational areas shaped behaviour without ever being formally recognised, and bilateral deals consistently favoured the commercial operator. The decisive failure was informational: a publicly announced habitat was missing from the shared operational picture, and a rival's reactor landing damaged it. Samuel Jardine and ESPI's Therese Jones have published the full account.

 

 

On 7 September, Open Lunar hosted a panel discussion on the sidelines of the 2026 Outer Space Security Conference in Geneva, with the Geneva Centre for Security Policy and the Global University Alliance for Outer Space Law and Policy Education. Experts from the US, China and Europe explored how existing international legal frameworks apply in an era of increasing strategic competition in cislunar space, alongside questions of peaceful use, resource utilisation, site coordination, dual-use, transparency and the risk of operational friction around key lunar locations.

 

 

Panellists included Open Lunar’s Samuel Jardine, Johns Hopkins University’s Professor Namrata Goswami, Dr Therese Jones from the European Space Policy Institute, and Professor Guoyu Wang from the Academy of Air, Space Policy and Law, Beijing Institute of Technology. It was moderated by Simon Cleobury from the Geneva Centre for Security Policy.

 

 

After the panel discussion, we hosted The Grey Side of the Moon, a lunar security and governance simulation at the Geneva Centre for Security Policy on the margins of UNIDIR's Outer Space Security Conference. Samuel Jardine designed and facilitated it, with the Centre's Simon Cleobury co-facilitating.

 

27 participants took part, including ambassadors and diplomats from government delegations working on disarmament, security, and space from both Artemis Accords and International Lunar Research Station signatory states, officials from United Nations agencies, and experts from the space, security, cyber, and legal professions. They were split into two competing state lunar programmes and one commercial operator, all seeking to operate in the same fictional lunar south pole region. The exercise combined physically modelled terrain and operational constraints with role-play, hidden objectives and competing interpretations of the Outer Space Treaty in a triple-blind scenario. The exercise explored how routine activities, including infrastructure deployment, resource extraction, surveillance and communications, could generate political and security concerns in a crowded, low-trust environment.

 

Many thanks to the participants, who gave up an afternoon of a busy week to join us and a huge thank you to the Expert Guides on the three teams, who supported a complex scenario mapping:  Christopher Johnson (Leiden University), Therese Jones (European Space Policy Institute), Thomas Gonzalez Roberts (Georgia Institute of Technology), Victoria Samson (Secure World Foundation), Almudena Azcárate Ortega (Secure World Foundation and UNIDIR), Jessica West (Project Ploughshares and the Centre for International Governance Innovation) and Clémence Poirier (ETH Zurich) as well as to TrivialTerrainUK for the design and creation of the fantastic lunar models that brought the scenario session to life. Be on the lookout for a more detailed report on this soon.

 

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