Stardust Publishes New Details on Its Climate Cooling Plans

Releasing principles is better than not releasing them, but I’m not sure this changes the fundamental picture. These guiding principles are extremely broad and self-authored – there are no mechanisms for independent verification, no processes for implementation, and crucially, the core technology itself remains proprietary and undisclosed. You can’t claim a commitment to transparency while keeping your particle secret.

We’ve seen consistently – both in SRM and across emerging technology domains – that ad-hoc, self-authored governance doesn’t produce the kind of public trust this field requires. Writing your own standards after years of operating without transparency or engagement doesn’t retroactively create legitimacy. This is further indication that we need consistent, credible, and independent research governance in SRM – which is exactly what a growing coalition of institutions is now building with the Solar Geoengineering Research Governance Platform.

Stardust has published a revised version of its guiding principles – one which now provides details we have not seen before. This is welcome, but insufficient for the world to understand the details of how Stardust is undertaking its work.

Publishing guiding principles is an important part of transparency. However, what is needed now is details on how Stardust has – and plans to – put into practice each of the principles. Otherwise, this exercise is more PR than real transparency.

This is particularly so for the section on “International Cooperation, Transparency, and Knowledge Sharing”. The principles are fine, but how Stardust is implementing these is what we need to know – and especially as Stardust’s for-profit approach is often in conflict with a number of the principles. For example, it would be useful to see how Stardust deals with “knowledge sharing” or “stakeholder consultation”, and most importantly the details of how its intellectual property strategy “will serve the public interest”.

Time has come for Stardust to go much further and address the specific actions it needs to undertake, consistent with the report I wrote in 2024 – a report that Stardust endorsed. Otherwise, that endorsement is meaningless.

Many of the guiding principles and safety requirements from Stardust are reasonable and echo what has been stated by others in the past, but Stardust is currently in clear violation of those principles. They have yet to share any specific information about research and development, yet they claim a commitment to transparency about the science. With contained outdoor experiments supposedly beginning this month, that lack is especially glaring.

The safety requirements document articulates well known concerns about SAI implementation and puts forth a number of somewhat arbitrary thresholds. There are a few technical oddities, such as the misconception that temperatures between 16–20 km across the entire tropics set stratospheric water vapor, when it is just the temperature in a narrow region in latitude and altitude. These documents do not increase my confidence that Stardust will contribute meaningfully in the near future.

Our mission at Stardust is to turn Sunlight Reflection Technology (SRT) from a theoretical concept into a safe, responsible, real-world option – and give governments the tools and information they need to decide whether, when, and how to deploy this technology.

Until now, the conversation about SRT has focused on whether it should be researched at all. We think the question should shift. With climate risk accelerating and more communities impacted every year, governments need a different answer: what would a safe, responsible SRT option actually look like?

We’re excited to release two documents that propose concrete answers. Our technical paper addresses the “what” question – which specific requirements an SRT system must meet to be safe and controlled. Our updated guiding principles address the “how” question – which ethical and governance standards this work must meet, developed with leading experts and grounded in accepted international frameworks.

We’re putting these forward for dialogue, input, and improvement, and we welcome thoughts and suggestions from the SRM360 community. Over the coming months, we’ll publish our scientific work, disclose our particle composition and core technologies, and continue opening our work to independent validation, allowing people to assess it against the requirements we’ve laid out and determine if we meet them.