Harvard preservationists rush to save astrophotographic plates from flood

Sky & Telescope : On 18 January some 500 000 photographic plates were threatened by water damage when the basement of the Harvard College Observatory flooded due to the rupture of a city water main. The plates contain images of star spectra taken by astronomers at Harvard and around the world from 1885 to 1992. The collection was in the process of being digitized, but only about one-third of the plates had been scanned when the disaster struck. After more than three feet of water had poured into the stacks where the plates were stored, staff from Harvard’s Weissman Preservation Center came to the rescue and removed some 61 000 soaked plates. The plates were then stowed in plastic boxes and put in semitrailer freezer cars to prevent the growth of mold. Over the next year and a half each plate will be thawed, cleaned, photographed, and inserted into a new sleeve. Harvard’s photographic plate preservation project is part of a larger effort to preserve the unique images captured by observatories around the world.