The Earth was, he believed.
Aristotle believed that the center of the earth was composed of the element earth, surrounded by water, then air, and finally fire. This concept was part of his theory of the four elements, which he believed made up all matter in the universe.
Aristotle had thought that the Earth was the Geo-centric or the center of the universe and everything circled or revolved around it. Copernicus thought that the Sun is the center of the universe. Copernicus' idea is called Helios-centric.
Most Ancient Greek philosophers assumed that the Sun, Moon, stars, and planets circled the Earth, including the systems of Aristotle (according the Aristotelian physics) and Ptolemy.
The idea that the Earth was the center of the universe was adopted because of the writings of Ptolemy and Aristotle. This was a common belief until the 1700s.
Perhaps you are confusing Universe with galaxy. Most galaxies have a black hole in their center. The Universe has no such thing as a center.
Aristotle was a geocentric believer( the earth was at the center of the universe.
Aristotle
Aristotle believed that the universe was made up of a series of concentric spheres, with Earth at the center. He thought that the stars and planets were embedded in these spheres and that they moved in circular orbits around the Earth.
Aristotle did not believe that the Sun was at the center; he thought Earth was. Aristarchus, a Greek astronomer, is probably the earliest person we know of who supported a heliocentric solar system.
Aristotle
Aristotle believed that the center of the earth was composed of the element earth, surrounded by water, then air, and finally fire. This concept was part of his theory of the four elements, which he believed made up all matter in the universe.
Aristotle believed in a geocentric model of the universe, with Earth at the center and celestial bodies orbiting around it in concentric spheres. He also theorized that the universe was eternal and unchanging.
Aristotle believed that the Earth was at the center of the universe, with all other celestial bodies revolving around it in a series of concentric spheres. This geocentric view of the universe contrasted with the later heliocentric model proposed by Copernicus.
Aristotle's model of the universe took into account the charted movements of the heavenly bodies, but was complicated by the assumption that Earth lay at the center of the universe.
Aristotle did not believe that the sun goes around the earth. He proposed a geocentric model of the universe where the earth was at the center and celestial bodies moved in circular paths around it.
Aristotle did not believe in a traditional heaven as depicted in religious doctrines. Instead, his concept of the divine was based on the unmoved mover, a purely intellectual principle that set the cosmos in motion. Aristotle's heaven is more of a philosophical idea representing the highest level of perfection and intelligence in the universe.
Aristotle believed that the universe was eternal and unchanging, with Earth at its center. He theorized that the stars and planets were embedded in a series of concentric spheres that rotated around the Earth. Aristotle also believed in the concept of natural motion and the existence of a fifth element, or quintessence, which made up the heavenly bodies.