The First Person to Theorize How Stars are Situated Within the Universe

Prior to the 16th century, it was believed that the Earth was the center of the universe with a belt of stars which rotated around it, exactly the same way in which planets orbit the central star of any solar system. These stars were believed to be fixed in their position as the constellations observed upon Earth do not alter greatly in their position or intensity in terms of what the human eye can perceive. Thomas Digges was the first person to propose that the stars are placed at different distances and in different positions, not in a ring of stars which stayed fixated, but rather in an infinite universe as distant points of light. Digges built upon the work of Nicolaus Copernicus by changing Copernicus’ original visual sketch of the planets and their orbital paths in that he removed the stellarum fixarum meaning “fixed stars” in Latin, and built a model in which stars were completely different in their distance relative to the Earth, with brightness controlled by how far or close a particular star was in proximity

The Reason Scientists Can Calculate the Distance and Velocity of Galaxies and Stars

Scientists understand the immense distance between galaxies and stars because of American astronomer Edwin Hubble’s theory of the expanding universe, as it is now understood that galaxies drift from the observer proportional to their distance, meaning the further a star is, the faster it continues to move away from the observer. This phenomenon is referred to as “Hubble–Lemaître’s Law”. Astronomers can calculate how fast a star is moving away from the Earth by observing the Doppler shift of the light it projects, as yellow light becomes red light as a star moves away and yellow light becomes blue light as it approaches closer. A formulae is then used to calculate the distance from the source point. Redshift is observed throughout the universe which confirms that the universe is indeed expanding at a phenomenal rate of speed