The data that showed planets travel in elliptical paths around the Sun was gathered by Johannes Kepler. He was a German astronomer who studied the meticulous observations of planetary positions made by his mentor, Tycho Brahe.

Kepler meticulously analyzed Brahe's data and, through years of calculations, formulated his Three Laws of Planetary Motion, which included the following:

1. Planets travel in elliptical orbits with the Sun at one focus. This was a groundbreaking discovery, as it challenged the prevailing belief that planets moved in perfect circles.

While Tycho Brahe gathered the data, Kepler was the one who analyzed it and formulated the groundbreaking laws that described the elliptical paths of planets.