• The area in which ammonia was detected on Pluto is about 200 kilometres wide (8 June, p 18).
• Earth takes 23 hours 56 minutes to complete one rotation and Mars takes 24 hours 37 minutes (15 June, p 38).
Letter: For the record – 13 July 2019
Published 10 July 2019
Issue no. 3238 published 13 July 2019
