Maps of Solar Eclipses from 1965 to 1969

In 1887, Theodor von Oppolzer published his epic Canon der Finsternisse (canon of eclipses). For decades, this work remained the comprehensive record of eclipses for many centuries past and future. It was not until 1966 until Oppolzer’s achievement was met with another similarly ambitious opus, the Canon of Solar Eclipses by Jean Meeus, Carl Grosjean, and Willy Vanderleen, all of Belgium. The range of eclipses in this work span from -1207 to 2509.

The calculations were done with an IBM 1620 data processing system. Thus, instead of three points calculated per eclipse, many points were calculated for each eclipse path with a much higher degree of accuracy.

Both the Canon der Finsternisse and Canon of Solar Eclipses share another innovation; the adoption of a new time scale useful for global and astronomical applications. Oppolzer had the foresight to apply Greenwich Mean Time for his work which made it useful throughout the world. The adoption of the Prime Meridian at Greenwich was just adopted by international agreement in 1884. Meeus, Grosjean, and Vanderleen likewise were early adopters of Ephemeris Time, internationally adopted in 1952 as a uniform time scale regulated by atomic clocks.