Well that was exciting! The test of a spacecraft impact on an asteroid (actually, a small asteroid orbiting a larger one). The image is of the surface a fraction of a second before impact.
Details from NASA here: https://www.nasa.gov/feature/dart-s-final-images-prior-to-impact
Last year we had intended to visit East Anglia on our way home from the nyckel;harpa gathering at Halsway. Unfortunately we had car problems which meant that we had to complete the journey by train, and abandon our holiday plans. This year we managed to do the holiday trip, though without a Halsway visit for once.