Sun (S) as one of many solar systems in cycling vortices. René Descartes' Principia Philosophiae, 1656 @LindaHall_org http://pic.twitter.com/3gjxip3WNG
— History of Astronomy (@hist_astro) June 24, 2015
from http://twitter.com/hist_astro
on: June 23, 2015 at 11:07PM