Further answers to various questions about the condition, motion, and effects of comets
This work is a continuation of E67. Euler gives credit to Kepler for the basic idea behind the theory he adopts for this paper. He says that the apparent zig-zag path that some comets seem to follow towards the end of their visibility is not the result of an irregularity in the real orbit of the comets; rather, it is the result of the motion of the Earth. In addition, Euler resolves some questions related to (1) the density of the atmosphere of comets; (2) the rotations of comets on their axes; and (3) the reason why the images of comets and planets are brighter in small telescopes than in large ones. Among the other things that Euler includes in this paper are (4) a demonstration of the true path of the comet of 1744 based on the observations of astronomers in Lausanne, Paris, and Berlin; and (5) a detailed daily record of the observations of an accomplished lady of the comet of 1744." (Based on Eric Aiton's introduction to Opera Omnia Series II, Volume 31.)
Original Source Citation
Berlin: Ambrosius Haude, pp. 1-92.
Opera Omnia Citation
Series 2, Volume 31, pp.151-194.