The Productivity of Ground-Based Optical Telescopes of Various Apertures

By scanning the papers published during the first quarter of 1996 in AA the weighted mean aperture was 2.52-m. By counting the 1996–2001 citations to those papers, we learned that 75% of the citations came from telescopes of <4-m apertures; the weighted mean aperture for the citations was 2.81-m. The mean citations per paper showed only a small dependence upon aperture. For example, telescopes of 5- to 10-m produce only twice as many citations per paper on the average as those of 1- to 2-m. Scanning the papers in the same journals during the first quarter of 200 I showed that 79% of the papers came from telescopes <4-m and the mean aperture was 2.81-m, which represent only small changes since I996. These numbers suggest that the bulk of our ground-based optical astronomical results come from telescopes of <4-m in aperture, and that is likely to continue to be true throughout the 2001–2010 decade. The 2001 decadal astronomy survey report made no recommendations for the maintenance, new instrumentation, and new construction of those telescopes that provide most of the astronomical results derived from ground-based optical telescopes. Although commendable in other respects, that survey represents an unrealistic appraisal of contemporary optical ground-based astronomy and its needs during this decade.