Jean-Philippe Loys de Cheseaux was an 18th-century Swiss astronomer and mathematician, born in 1718 in Lausanne. He is best known for his work in observational astronomy and for his contributions to the understanding of comets. Cheseaux was particularly interested in the periodicity of comets and made significant observations that helped advance the field. In addition to his astronomical work, Cheseaux was also involved in the study of geography and mathematics. He published several papers and was a member of various scientific societies. His contributions laid the groundwork for future astronomers and helped to enhance the scientific community's knowledge during his time.