Submitted by S. Brereton on Thu, 09/10/2025 - 09:40
The GUEST mission concept (Gravitational Universe Exploration with Satellite Tracking), co-proposed by Alex Jenkins, Gavin Boyle Fellow in Cosmology at KICC and EPSRC Stephen Hawking Fellow, has been selected to advance to the next phase of the European Space Agency’s 2025 call for “fast” (F-class) missions.
The project aims to detect gravitational waves at microhertz frequencies via laser ranging of two or more geocentric satellites. This will allow GUEST to explore a new frequency window in the gravitational-wave sky, offering a unique probe of sources such as massive black hole mergers, as well as hypothesised cosmological background signals. GUEST’s broad science case also includes novel searches for ultralight dark matter and precision tests of general relativity.
The GUEST proposal leverages a new gravitational-wave detection method developed by Alex Jenkins in collaboration with GUEST PI Diego Blas (IFAE, Barcelona) in work published in 2022. This effort has now developed into an international collaboration of more than forty scientists, in which Alex is leading one of the working groups to develop GUEST’s science case.
In the next phase of the ESA call, GUEST will compete with other mission concepts across different areas of space science to determine which projects will move forward to implementation.
Image: Eve Barlier
