From the November 2005 issue

The discoverers of Kapteyn’s Star

Two men with different backgrounds worked together to discover this speedy star.
By | Published: November 28, 2005 | Last updated on May 18, 2023
Tracking Kapteyn's Star
Kapteyn’s Star sails through the sky at a rate of 8.7″ a year. This chart shows where the star has been, and where it’s headed.
Astronomy: Roen Kelly
Jacobus Kapteyn and Robert Innes discovered Kapteyn’s Star — originally named “Cordoba Zone 5 hours 243” because of its location — in 1897. Kapteyn was in Holland analyzing photographic plates taken at the Cape Observatory in South Africa, and Innes was an assistant at the Cape Observatory. Kapteyn did not find a star in its documented location and asked Innes to look for it in the sky. Innes found the star, but it was east of where it should have been. They had discovered the fastest moving star across the sky (the record, however, has since been broken by Barnard’s Star).

Even though Kapteyn and Innes worked together, their backgrounds couldn’t have been more different. While Kapteyn was a college and graduate-trained astronomer, Innes was an amateur-turned-professional, with no formal education.