Uploaded September 2016 | Updated September 2026, 2 weeks ago

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Produced on site at New Scientist Live 2016! This was a question from Owen, age 6, posted on the #MendeleyWall, a giant wall in the Mendeley booth where people wrote down the questions they had for science. We visited the booth of the British Astronomical Association to find out! This answer was calculated by Mike Frost (britastro.org/history/mikeFrost.html) and illustrated by Lisa Dennison (sciencesketches.org).