Astral Systems
Bristol-based deep-tech company developing modular multi-state fusion reactors that run several fusion reactions in parallel rather than one large tokamak.
Astral Systems raised a £23m Series A on 25 June 2026, led by Mercia Ventures and Tees River, to scale production of medical radioisotopes used in cancer diagnosis and therapy from a former power station site in Gloucestershire.
Last refreshed: 31 July 2026 · Appears in 1 active topic
Can fusion hardware solve the UK's medical radioisotope shortage before 2027?
Timeline for Astral Systems
Mentioned in: South West fund hits £157m, 283 firms
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UK Startups and InnovationRaised a GBP23m Series A to commercialise modular fusion reactors
UK Startups and Innovation: Astral raises GBP23m for cancer isotopesBackground
Astral Systems was founded in Bristol in 2021 by Charles Firestone and Dr Tom Wallace-Smith to build modular multi-state fusion reactors that run several smaller fusion reactions in parallel rather than chasing one large tokamak. The approach targets a persistent shortage of medical radioisotopes used in cancer diagnosis and therapy, which today are made in a small number of ageing reactors, leaving supply fragile.
Astral treats fusion hardware as a medical-supply tool rather than a future power source, positioning its reactors to compete on isotope production timelines rather than on grid electricity generation, a niche distinct from most fusion companies chasing commercial power.
Astral raised £23m for cancer isotopes
Astral Systems closed a £23m Series A on 25 June 2026, led by Mercia Ventures and Tees River with Daphni, Speedinvest and Playfair Capital, to scale production of medical radioisotopes such as Actinium-225 and Lead-212, used in targeted cancer therapies with few reliable production sources today . The capital funds a scale-up facility at the former Berkeley Power Station site in Gloucestershire.
Several of Astral's reactors already operate at Technology Readiness Level 9, having generated over £3m in research-contract revenue before this round, and the company is working with McMaster University and Brazil's Institute for Energy and Nuclear Research to bring an isotope to market by early 2027.
