Now with his greater understanding, Horrocks set to work improving Kepler 's tables. Kepler had predicted a transit of Venus would occur in 1631, and that another would occur in 1761. Kepler had died in 1630 but even if he had lived he would not have seen the transit of 1631 since it was not visible in Europe as the sun was below the horizon during the transit.
Ngayon sa kanyang higit na unawa, Horrocks-set sa trabaho pagpapabuti ng Kepler 's tables. Kepler had hinulaang ng transit ng Venus ay magaganap sa 1631, at iba pang nais na nangyari sa 1761. Kepler ay namatay sa 1630 ngunit kahit na siya ay nanirahan siya ay hindi nakita ang sasakyan ng 1631 dahil ito ay hindi makikita sa Europa bilang ng mga araw ay sa ibaba ang abot-tanaw sa panahon ng sasakyan.