Image: Horrocks Venus in sole

Description: A representation of Jeremiah Horrocks' observation of a Venus transit across the Sun in 1639, publshed by Johannes Hevelius with Horrocks' Venus in sole visa in 1662. Hevelius seems to have been confused about the orientation of the image projected by Horrocks' Galilean telescope and has shown an inverted mirror image of what he would have seen. Horrocks wrote: "I found that the shadow of Venus at the aforesaid hour, namely fifteen minutes past three, had entered the Sun's disk about 620 30', certainly between 600 and 650, from the top towards the right. This was the appearance in the dark apartment; therefore out of doors beneath the open sky, according to the laws of optics, the contrary would be the case, and Venus would be below the centre of the Sun, distant 620 30' from the lower limb, or the nadir, as the Arabians term it." The image also shows Venus as three evenly spaced disks whereas the observations were made at irregular intervals. see: http://transitofvenus.nl/wp/2012/01/25/what-did-horrocks-really-see/
Title: Horrocks Venus in sole
Credit: Scanned and digitised from the original book by Franz Kerschbaum & Thomas Posch, Vienna University. link to the original scan. Selected and cropped from theabove source by Jotempe
Author: Jan Hevelius
Permission: PD-old
Usage Terms: Public domain
License: Public domain
Attribution Required?: No