The European Space Agency is pressing ahead alone on its Envision mission to Venus after NASA signalled it likely cannot deliver a US-built radar instrument it had promised, due to budget pressures from the Trump administration's proposed cuts to NASA science funding. Envision will map the Venusian surface at ten times the resolution of NASA's 1990s Magellan radar mission, aiming to peer through the planet's thick sulphuric acid clouds and search for signs of active volcanism. The setback underscores growing strain on transatlantic space partnerships as the White House seeks to scale back NASA's international science commitments.

Under a 2024 agreement, NASA was to supply Envision's primary radar instrument and Deep Space Network communications support, while ESA built the spacecraft, other instruments and provided an Ariane 6 launch. Although Congress restored most proposed cuts, planetary science funding still fell around $220 million short of the previous year, forcing NASA to scale back international collaborations, including contributions to Envision and two other European-led missions, LISA and New Athena. ESA has since contracted UK and Italian firms to develop a replacement European radar matching the original's capabilities, with the mission still targeting a 2031 launch, though NASA had already spent over $50 million on its now-uncertain contribution.