On the atmosphere of the moon as proved by the last annular solar eclipse
Euler's goal in this paper is to show that certain phenomena observed during the eclipse of July 25, 1748 are evidence that the moon has an atmosphere which is almost 200 times less dense than that of the Earth. (Based on Eric Aiton's introduction to Opera Omnia Series II, Volume 31.)
Original Source Citation
Mémoires de l'académie des sciences de Berlin, Volume 4, pp. 103-121.
Opera Omnia Citation
Series 2, Volume 31, pp.239-256.