1 “... the properties of any celestial body - be it a planet or a star - all information we wish to gain can reach us...”

2 “... destined to be the first celestial body outside the confines of our own planet to be reconnoitered at a...”

3 “.... (in 1676, to be exact) the timings of the eclipses of the satellites of Jupiter by their central planet...”

4 “... of all celestial bodies outside the gravitational confines of our planet could be studied only at a...”