Changes

Modern astronomy developed in the 19th century, where experiments and further observations led to the understanding of basic chemistry, such as understanding how hydrogen and helium formed the basic components of the universe. Major recent advances have focused understanding the expansion of the universe. This includes the understanding of the origin of the universe and big bang theory became a major discovery. These developments also led for the need for increased developments in a variety of other technologies, including in developing exploratory satellites, telescopes, and computers to process data from a variety of developed sensors.<ref>For more on 19th century and later development in astronomy, see: Krebs, R. E. (2004). <i>Groundbreaking scientific experiments, inventions, and discoveries of the Middle Ages and the Renaissance.</i> Westport, CT: Greenwood Press.</ref>