Reino Antero Hirvonen

Reino Antero Hirvonen (1908–1989) was a famous Finnish physical geodesist, also well known for contributions in mathematical and astronomical geodesy.

He worked at first at the Finnish Geodetic Institute under W.A. Heiskanen on gravimetric geoid determination. In 1950 he succeeded Heiskanen as Professor of Geodesy at the Helsinki University of Technology.

He also took an active interest in astronomy, acting from 1956 to 1964 as a vice president of the Finnish amateur astronomical society Ursa.

Hirvonen R.A. participated in 1930s building and measuring the Finnish landscape to higher accuracy than before by building triangulation measuring towers and developing new mathematical algorithms for the manual calculations (before the computer era).

In 1947 he led the team of Finnish scientist to Brazil to measure the distance between South America and Africa. (Kukkamäki was leader of the team sent to Africa.) They succeed with measurements using a triangulation method based on measuring points in Brazil and Africa. The third point of the triangle was the solar eclipse happening that year, which was visible in both Africa and South America. Using the most accurate timing available signals for the solar eclipse measurements, they were able to calculate the distance between Africa and South America to a higher accuracy than ever before.

1951–1952 and 1954–1955 he lectured in the Department of Geodetic Science at The Ohio State University, in Columbus, Ohio (USA). He educated the students about navigation using the stars as reference points. Later it helped the USA to fly to the moon.