The Contribution of A. W. Roberts’ Observations to the AAVSO International Database

Volume 47 number 2 (2019)

Download this article (pdf)

Tim Cooper

Astronomical Society of Southern Africa; tpcoope@mweb.co.za

Abstract

Alexander William Roberts observed around one hundred variable stars mainly during the period 1891–1912. In 2004 we succeeded in digitizing around 70,000 of his visual observations which were added to the AAVSO International Database (AID), ensuring these are available for further study. These observations, many of which pre-date the existence of the AAVSO, extend the period of observation of many variable stars by one or two decades earlier. This paper summarizes the observations made by Roberts and added to the AID, and gives examples of some apparent discrepancies which warrant further investigation.