Johannes Kepler
3 records
1600s
1 record
1609
Kepler publishes his first two planetary laws
Kepler described elliptical planetary orbits and the equal-area law using Tycho Brahe’s observations.
1610s
2 records
1610
Kepler suggests a solar influence on comet tails
In a letter to Galileo, Kepler proposed that a solar breeze pushes comet tails away from the Sun.
1619
Kepler’s third planetary law published
Kepler related a planet’s orbital period to the size of its orbit.