Professor Guillermo Haro was born in Mexico City during the height of the Mexican revolution on March 21, 1913. Though he is well-known as a very influential name in the field of astronomy in Mexico, he started out as a philosophy student at the National University of Mexico (UNAM). His remarkable milestone in the development of astronomy began when he was hired as an assistant at the then newly-founded Observatorio Astrofisico de Tonantzintla in the year 1943. He went to the United States to further his training on astronomy; he worked at the Harvard College Observatory from 1943-1944 to finance his stay in the U.S.
When he returned to Mexico in 1945, he continued his works at the Observatorio Astrofísico de Tonantzintla. There he commissioned the creation of the 24-31 inches Schmidt camera. It is this invention that allowed Haro to better study on the existence and nature of extremely red and extremely blue stars. Then in 1947, he began working at the Observatorio de Tacubaya of the UNAM.
The contributions that Guillermo Haro has given to observational astronomy in Mexico were very remarkable. He was the one who detected the huge number of planetary nebulae in the galactic center’s direction. He also made the same discovery to that of George Herbrig; which is the detection of non-stellar concentrations of very highly- dense clouds close to the area where a star was recently formed. It is now called the Herbig-Haro obejects. The discovery of flare stars in the location of the Orion Nebula and the discovery of stellar aggregates of various ages were all made by Guillermo Haro with the help of his co-workers. His passion for astronomy and his intense activity in discovering flare stars were his life’s works until he died on April 26, 1988.
Other significant studies and research projects made by Haro included the list of 8746 blue stars in the north galactic pole direction; which was made together with W.J. Luyten in 1961. His works performed with the use of the 48-inch Palomar Schmidt with the usage of tri-colored image technique made in Tonantzintla. He also listed no less than 50 objects which were actually quasars. In 1956, he made a compilation of the list of 44 blue galaxies. He is also the one who discovered several T Tauri stars, one supernova, a dozen novae and a comet.