Astronomy is a natural science attracting substantial public interest. On a human scale, most individual celestial objects are essentially unchanging but is the same true for interest in astronomy research? This article uses the popular online encyclopedia Wikipedia as a proxy for public interest in academic research and assesses the extent to which it cites astronomy and astrophysics articles published between 1996 and 2014. Automatic Bing searches in Webometric Analyst were used to count the number of citations to astronomy and astrophysics articles from Wikipedia. The results show that older papers from before 2008 are increasingly less likely to be cited. This is true overall and in most of the major language versions of Wikipedia, although it may reflect editors’ interests rather than the public’s interests. This is consistent with a moderate tendency towards obsolescence in public interest in research, although it is probably affected by the dates on which most Wikipedia content on the topic was created. Papers may become obsolete if they report evidence that are later superseded by improved data or if they propose a model that is later replaced
