Israeli-American start-up Stardust Solutions has raised $75 million to develop technology designed to reflect sunlight away from Earth, as the company seeks government customers for a controversial approach to reducing global temperatures.
The funding includes a $60 million investment round announced in October 2025 and led by Lowercarbon Capital, the climate technology investment firm co-founded by Chris Sacca. Other investors include Exor, the Agnelli family’s investment company and a major shareholder in Ferrari, as well as Future Ventures, Future Positive, Lauder Partners, Attestor, Kindred Capital and former Facebook executive Matt Cohler.
Stardust was founded in March 2023 by Israeli physicists Yanai Yedvab, Amyad Spector and Eli Waxman. Yedvab and Spector previously worked as nuclear physicists for the Israeli government.
The company is registered in Delaware and headquartered near Tel Aviv. It says it has no affiliation with the Israeli government.
Yedvab told Politico that investors supported the development of what he described as a “safe and responsible and controlled option for sunlight reflection.”
The technology being developed by Stardust falls under stratospheric aerosol injection, a form of solar geoengineering also known as solar radiation modification. The approach aims to reflect a small amount of solar energy back into space rather than removing carbon dioxide from the atmosphere.
The concept is based partly on the natural cooling effects of major volcanic eruptions. When volcanic compounds reach the stratosphere, they can form particles that reflect sunlight and temporarily lower global temperatures. The 1991 eruption of Mount Pinatubo provided a major example of this effect.
Instead of releasing sulphur dioxide, Stardust says it is developing proprietary reflective particles, along with systems for dispersal and atmospheric monitoring. The company is working towards aircraft-based technology.
Stardust has hired Washington lobbying firm Holland & Knight as it seeks to establish a regulatory framework and explore potential US government contracts. The company says its current work is focused on research and development rather than deployment.
“Our goal is to turn SRM from a scientific concept into a safe and practical option,” Stardust said, arguing that climate cooling could eventually provide an emergency response if emissions cuts fail to prevent dangerous warming.
The proposal has attracted strong criticism from environmental groups. The Center for International Environmental Law warned that solar geoengineering could produce unpredictable effects and uneven impacts around the world.
Critics have also raised concerns about “termination shock”. Because the technology would not remove carbon dioxide, abruptly ending large-scale cooling after prolonged use could result in rapid warming.
Stardust is one of several groups exploring climate cooling. US start-up Make Sunsets has launched weather balloons carrying sulphur dioxide and sells related “Cooling Credits”.
Other projects have been abandoned or remain focused on research. Harvard ended its proposed SCoPEx experiment in 2024 following controversy over governance and consent.
In the UK, the Advanced Research and Invention Agency is funding a £56.8 million programme examining whether climate cooling technologies could be feasible, scalable, safe and governable.
