DASCH Data Release 4 Now Available
Jonathan Grindlay Center for Astrophysics | Harvard & Smithsonian
The plate-scanning project Digital Access to a Sky Century @ Harvard (DASCH) has posted its fourth data release, DR4, as of 17 March 2015. This includes data from 22,275 plates covering the galactic latitude range b = 45° to 30° and brings the total number of plates scanned to ~95,000, or ~20% of the estimated total. Scanning for DR5 (b = 30° to 15°) is ~60% complete (and included in the scanned plates total given above) and should be released by June.
We have decided to continue the progression of scanning through the galactic plane and down to the south galactic pole. Rather than our original plan of DR6 being b = -90° to -75°, it will be from b = +15° to 0°, and DR12 from b = -75° to -90°. Our original reason for the plane being last was to improve crowded-field photometry. But these improvements are now possible by our planned re-processing of the entire database, which can be done on the Harvard Odyssey cluster.
When making use of DASCH light curves, images, or data, please acknowledge that support for DASCH is from NSF grant AST-1313370.