William Gershel (1738 - 1807).
Gershel was the pioneer in everything he did. Among people who were able to make a telescope he was a constructor of the great telescopes and the great observer. He greatly influenced the history of astronomy as a thinker, who described our Universe. With the help of his own observations he was the first who evaluated the dimensions of our "star house" - the Galaxy. Gershel twice widened the Solar system and "turned" the Sun, proving its motion in the Universe.
In March 1774 Gershel observad the beautiful light nebula in Orion constellation with the help of his telescope-reflector of Newton's system - 5,5 feet length (~2m) and 20 sm in diameter.
From the 1775 the scientist made 4 systematic observations of the star sky during several years. In March 13, 1781 Gershel opened the planet Uranus (after the first attempt of Babylonians). The Solar system became twice more. Besides he opened two satellites of Uranus (1789) with the reverse motion (1797) and two new Saturn satellites (1789). He exactly calculated the period of Saturn's rotation and its rings and many other things unknown before. In 1783 Gershel discovered the Sun's motion in the Space and its direction. He also investigated the double and multiple stars. He discovered the heat beams or infrared irradiation.
But the most important achievement of general Universe construction. The 20 feet telescope of Gershel opened the nature of the mysterious "milky nebulas" which turned to be the star congestions. Gershel turned to be a philosopher when he generated a theory of the nebulas layer spreading, the evolution of space substance and the stars formation from the diffusional material.