Jeremiah Horrocks had attempted to produce an estimate based on his observation of the 1639 transit (published in 1662), giving a solar parallax of , similar to Wendelin's figure. The solar parallax is related to the Earth–Sun distance as measured in Earth radii by
Jeremiah Horrocks attempted to calculate an estimate based on his observation of the 1639 transit, which was published in 1662. His calculation produced a solar parallax value similar to Wendelin's findings. The relationship between the solar parallax and the Earth–Sun distance is expressed in terms of Earth radii.