Thomas Joins First Light Fusion as New CEO
Portfolio - People | Mar 04, 2025 | Business Cloud

First Light Fusion, a UK-based technology firm specializing in fusion power, has announced the appointment of Mark Thomas as their new CEO. Thomas was previously the CEO of Reaction Engines, a company that sought to revolutionize hypersonic flight but has since collapsed, resulting in significant layoffs. His experience includes a long tenure at Rolls Royce. First Light Fusion has abandoned its earlier plans to build a power plant and instead will focus on forming commercial partnerships with both fusion and non-fusion sectors, including collaborations with NASA and the Open University. This pivot aligns with the company's commitment to leveraging its amplifier technology in various applications, from commercial fusion to space exploration and defense. The strategy aims to develop a supply chain for viable fusion power plants, harnessing British innovation.
Sectors
- Energy
- Aerospace and Defense
- Research and Development
Geography
- United Kingdom – First Light Fusion and Reaction Engines are both based in the UK.
- United States – The partnership with NASA, a key US agency, highlights relevant activities in the US.
Industry
- Energy – First Light Fusion is part of the energy sector, focusing on fusion power technology.
- Aerospace and Defense – The company's partnerships with NASA and developments in hypersonic travel technology place it within the aerospace and defense industry.
- Research and Development – The involvement with universities and continued focus on technology innovation align with R&D activities.
Financials
- 160m – Debt reportedly associated with Reaction Engines prior to administration.
Participants
Name | Role | Type | Description |
---|---|---|---|
First Light Fusion | Employer | Company | A UK tech firm specializing in amplifier technology for commercial fusion power plants. |
Mark Thomas | New CEO | Person | Former CEO of Reaction Engines, now leading First Light Fusion. |
Reaction Engines | Previous Employer | Company | A UK-based company focused on hypersonic technology, now defunct. |
NASA | Partner | Government | US government agency partnering with First Light Fusion on space exploration technology. |
Open University | Partner | Company | Collaborating on testing the applicability of amplifier technology in space exploration. |