Lascar (5400 m asl), an active volcano located about 40 km south of the ALMA construction site, erupted around 11:00 am on April 18 local time (midnight on April 19: JST). Lascar is one of the most active volcanoes in Chile and its eruptions have been recorded on average every 5.8 years since 1848. According to an analysis by a specialist, its volcanic activities were predicted to have little impact on the ALMA site due to the distance and wind direction from the volcano. This eruption actually had no influence on our construction. The picture shows ALMA OSF (Operations Support Facility) staff with the eruption column from Lascar in the background. This picture was put on the bulletin board of JAO (Joint ALMA Office).