Not a big surprise, but the higher the amount of local (< 100 km from venue) participation, the smaller the average emissions. However, even meetings with few local attendees can have travel emissions below the average.

Most astronomy meetings are ≤ 100 attendees in size, but depending on the meeting venue, average emissions can be very high if most people have to fly medium to long distance. For large meetings, average emissions scatter around the average value of 1t CO2e per person.