Galileo Galilei’s great contribution might be…

…the scientific consideration of the line of moons along Jupiter that can be seen well in this image. It is interesting Mr. Galilei described the device he invented to observe the truth of planetary motion as a secret weapon for the protection of the state (pun intended).

APOD: 2009 July 14 – Moons and Jupiter
the exposure captures Jupiter’s own Galilean moons lower right as tiny pinpricks of light, lined up and hugging both sides of the solar system’s ruling gas giant