German pastor who made two major discoveries in the early days of telescopic astronomy, jointly with his eldest son, Johannes Fabricius (1587–1615).
As was common for Protestant ministers of the day, he dabbled in science: his particular interest was astronomy. Fabricius corresponded with astronomer Johannes Kepler.
Fabricius discovered the first known periodic variable star (as opposed to cataclysmic variables, such as novas and supernovas), Mira, in August 1596. At first he believed it to be “just” another nova, as the whole concept of a recurring variable did not exist at the time. When he saw Mira brighten again in 1609, however, it became clear that a new kind of object had been discovered in the sky.
Two years later, his son Johannes Fabricius (1587–1615) returned from university in the Netherlands with telescopes that they turned on the Sun. Despite the difficulties of observing the sun directly, they noted the existence of sunspots, the first confirmed instance of their observation (though unclear statements in East Asian annals suggest that Chinese astronomers may have discovered them with the naked eye previously, and Fabricius may have noticed them himself without a telescope a few years before). The pair soon invented camera obscura telescopy so as to save their eyes and get a better view of the solar disk, and observed that the spots moved.
He died at Osteel on 7 May 1617: after denouncing a local goose thief from the pulpit, the accused man struck him in the head with a shovel and killed him.

Link to Wikipedia biography