Rain didn’t stop us. Hundreds of visitors flooded the ESO-ALMA facilities on Chilean Astronomy Day 2026, turning what could have been a quiet Friday into one of our most vibrant outreach events of the year.

From the moment doors opened, attendees dove into a packed program designed to make cutting-edge astronomy tangible. Guided tours of the ALMA Remote Control Room and a live feed from ESO’s Paranal Observatory pulled back the curtain on daily operations. Solar observation sessions—led by AUI/NRAO volunteers—added an element of suspense to the day. With cloudy skies forcing a last-minute pivot to an alternative plan, patience paid off: gaps in the clouds gave some lucky visitors a rare, direct glimpse of the sun through the telescopes. Informational booths and hands-on workshops—from comet building to telescope assembly—kept curiosity running high across every age group.

The talks were equally compelling, covering light pollution, the role of women in astronomy, the Stax3plorer student project, and a forward-looking presentation on ESO’s ELT and ALMA 2030. An inflatable planetarium, a meteorite exhibition, and dedicated activity zones for children ensured families had plenty to explore throughout the afternoon.

As the rain intensified, outdoor activities wrapped up early, and the planned astro-concert had to be cancelled. The event closed instead with the talks, ending the day on a thoughtful note—with the public putting their questions directly to our astronomers in open-mic sessions that proved the weather couldn’t dampen the enthusiasm.

More than a showcase, the Open House was a reminder of why outreach matters. Every booth, workshop, and tour reflected the expertise and dedication of our teams—and their ability to make complex science genuinely accessible. The event deepened our ties with the community and reaffirmed ALMA’s role as a leader in science communication.