Lange Nacht der Astronomie is a nationwide German event that invites people to observe the sky, explore the universe and share the excitement of astronomy. The 2026 edition takes place on 12 August, coinciding with a solar eclipse, and is organized by the Stiftung Planetarium Berlin, the Astronomische Gesellschaft, the Gesellschaft Deutschsprachiger Planetarien, the Vereinigung der Sternfreunde and the Federal Ministry of Research, Technology and Space, together with astronomy organizations across Germany.

Rather than selling products, the event offers free public programs and experiences for visitors of different ages and levels of interest. Activities include solar and night-sky observations with telescopes, planetarium shows, lectures, guided tours, hands-on activities and livestreams. The 2026 program features opportunities to view the partial solar eclipse and, later, the Perseid meteor shower, alongside observations of stars, clusters and galaxies. Participating institutions include planetariums, observatories, universities and astronomy groups in locations across the country. Events are hosted at venues and outdoors, with schedules and offerings varying by location.