Ars Technica: On Tuesday, UK-based Reaction Engines signed a £10 million contract with the European Space Agency for the development of their Synergistic Air-Breathing Rocket Engine (SABRE). That agreement fulfilled a funding requirement for an additional £50 million from the UK Space Agency. Reaction Engines says that the new funding comes on top of an earlier £20.6 million from BAE Systems and allows the company to develop a ground-based demonstration SABRE engine by 2020. SABRE is a hybrid rocket–jet engine that functions as a jet at low altitudes and as a rocket at high altitudes. The company says the design is possible because of its pre-cooling heat exchanger, which can cool incoming air from 1000 °C to –150 °C in 1 ms (and prevent freezing by injecting methanol into the cooling system). In theory, the engine would be able to power a spaceplane from a horizontal take off all the way to low Earth orbit. This single-stage-to-orbit reusable launch system would be a potentially significant alternative to traditional rockets.
The finding that the Saturnian moon may host layers of icy slush instead of a global ocean could change how planetary scientists think about other icy moons as well.
Modeling the shapes of tree branches, neurons, and blood vessels is a thorny problem, but researchers have just discovered that much of the math has already been done.
January 29, 2026 12:52 PM
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