The Kepler space telescope launched in March, 2009, to search for terrestrial planets around other suns. One month later, five Jupiter-like planets had been discovered. As of 2015, the Kepler telescope has discovered a total of 1,000 confirmed planets.

The University Libraries’ Kepler collection includes all 11 major works published during his lifetime, and a large number of his minor works. In his immediate response to Galileo’s telescopic discoveries, Kepler suggested that unknown planets might exist, and might be inhabited.