GAAC Speaker Friday Night 5/12: Ed Los, Rescuing Valuable Historic Astrophotos


At this month’s GAAC meeting, 8:00 Friday night, May 12, at the Lanesville Community Center, we are thrilled to host Ed Los, a long-term member of the “Digital Access to a Sky Century team at Harvard” (DASCH). Ed will bring us up to date on the project to digitize over 500,000 images of the night sky collected on glass photographic plates between 1885 and 1993.


Image: Portion of Plate b41215 of Halley’s comet taken on April 21, 1910 from Arequipa, Peru with the 8-inch Bache Doublet, Voigtlander.

These images offer us far more than mere historic value. They have greatly advanced what we know of the composition of stars, their inherent luminosities and distances, and, as a 100-year record of the skies, they are sure to continue to inform our understanding. Already as part of this ongoing project more than 162,000 plates, along with data from a card catalog and 1200 associated log books, have been scanned into digital files, to preserve them and make them more readily available to researchers.

Ed will explain the ongoing project and its importance to our knowledge of the night sky, and will tell us some of the many ways that these data are even now helping us understand the universe around us. We’re very pleased to have Ed as this month’s presenter, for what is sure to be an entertaining and informative evening at GAAC. We hope to see you there.

The Gloucester Area Astronomy Club meets on the second Friday of the month at 8:00 at the Lanesville Community Center, 8 Vulcan Street, Lanesville. All are welcome; no special knowledge or equipment is needed to have a great time. There is plenty of free parking, and there is no cost. For more on the astronomy club see our website or Facebook page, or follow us on Twitter, @gaacster. Come see us!