As longer-term readers of greg.org know, I am slowly trying to locate an original copy of the National Geographic Society-Palomar Observatory Sky Survey, an 1870-plate portrait/catalogue of the visible universe [or the universe visible from the Palomar Observatory, anyway] taken at Caltech in the early 1950s. Then I will also print one. There are also loose vintage prints to be found.
Anyway, in the process, I've been documenting bits of the history of the making of the NGS-POSS I. [A second sky survey, the POSS-II, was made beginning in the late 1980s.] It's almost embarrassing that it's taken me this long to look into who actually made it, took the pictures, checked them, made the prints.
After the jump, then, a brief history of the making of POSS-I, as presented by Neill Reid and S. Djorgovski in the proceedings of the Astronomical Society of the Pacific's 1992 conference, Sky Surveys, Protostars to Protogalaxies:
The blue and red photographic sky surveys completed at Palomar in the late 1950s (Minkowski & Abell, 1963) have become indispensable to observational astronomers, whether as an optical reference for non-optical surveys or as a research tool (for starcounts, galaxy counts, proper motion surveys, and the like) in their own right. Photographic technology has moved on considerably since the 1950s, and Palomar recently embarked on a second sky survey, currently approaching 50% completion, aimed to match the depth and resolution of the SERC/ESO surveys of the southern skies [plates from which Thomas Ruff used in his Sterne series, btw. -ed.]
It is interesting to compare the origins of the two surveys. There is no easily identifiable single person responsible for the idea of the first survey--it seems to have been a consensus decision, with Hubble, Humason, Baade, Bowen and Minkowski amongst the prime movers. (Zwicki, interestingly, was more in favor of an expanded supernova search.) The oldest description located so far is in a letter dated 20th January 1949 from Hubble to G.H. Hall (Caltech administration), where Hubble describes using the year-old [48-inch Oschin] Schmidt for a main sky survey that would extend to declinations of -27 degrees, with a possible later supplement to -45 deg. (which was the final plan adopted). The same day, Hall contacted Dubridge (the Caltech president) suggesting that the National Geographic Society might be interested in sponsoring the programme. NGS was contacted on February 16th and (obviously) did express interest, with the result that the draft agreement was signed on 18th May, the first funding installment received on June 17th and the first plate (rejected!) taken on November 11, 1949. The original plan was for the survey to take only 4 years. In fact, 99% of the plates were taken by June 20, 1956--and the final 1% was not completed until Dec. 19, 1958. Planners of other surveys take note.
The main impetus for the original survey was the desire to complement the capabilities of the newly-available 200-inch telescope--similarly, the second survey sprang from the requirements of both space-bourne observatories (such as IRAS, HST, and Einstein) and the large aperture ground-based telescopes that were starting to be discussed in the late 1970s...
So the surveys are designed to use the most advanced technology available, or conversely, the limits of what might be surveyed are constrained by the performance of the technology. it's a mix of subjectivity, or arbitrariness, and empiricism. And it seems it is constantly rendered obsolete by advances in tools.
Oh, and Abell. George O. Abell's 1958 thesis consisted of a galaxy clusters catalogue compiled from the POSS plates he and A.W. Wilson helped produce.