A period called Renaissance that's when the Solar system was discovered. A astronomer called Nicolaus Copernicus said that the Sun was in the centre of the Universe, and that the rest of the planets orbit in a perfect circle. In 1571 Johhanes Kepler didn't believe it was true so he tried to figure it out it took him ages he nearly gone mad, but he discovered that the planets orbit in a elliptical orbit around the sun.
Contribution to our Knowledge
It tells us more about how the solar system works and how our planets orbit and how the sun controls the way the planets move. It tells the astronauts where to land