Historical clue formulations

• The Father of Modern Physics — 2021-03-03
• Astronomer who first observed Saturn's rings — 2019-10-30
• "Two New Sciences" author — 2015-08-16
• Astronomer who discovered the main moons of Jupiter — 2015-04-13
• "Sidereus Nuncius" author — 2007-04-05
• Spacecraft to Jupiter — 2005-12-13
• 1600's stargazer — 2004-03-09
• Telescope pioneer — 2003-09-02
• Classic Italian astronomer — 2001-07-30
• Early sunspot studier — 2001-06-23
• 1989 NASA launch — 1996-06-20