Location: Room A2, Conference Space, 2nd floor, New Student Centre
DASCH Project Update
Edward Los (Nashua, NH, USA)
The “Digital Acesss to a Sky Century @ Harvard” (DASCH) project is an effort to scan the glass plate negatives in the archive of the Harvard College Observatory for the purpose of generating light curves which can span 100+ years. The logbook digitization project is complete. The scanning project is 77% complete. With the recent DR6 release, all of the photometry North of the galactic plane is now available. We have recalibrated nearly all of the photometry with the ATLAS refcat2 catalog. Parallel to the scanning, there are efforts to improve the yield with new algorithms for multiple exposure processing and astrometry.
The Eye is Mightier than the Algorithm: Lessons Learned from the Erroneous Classification of ASAS Variables as “Miscellaneous”
Dr. Kristine Larsen (Professor of Astronomy and Faculty Coordinator, Copernican Planetarium, Geological Sciences Dept., Central Connecticut State University)
The superior ability of the human eye and brain to detect patterns in data is central to many crowd sourcing and citizen science projects such as Galaxy Zoo and Planet Hunters TESS. This poster summarizes lessons learned in a much smaller scale project, the largely student-driven identification and proper reclassification of selected variable stars that have been erroneously flagged as “miscellaneous” by the algorithms of the ASAS (All Sky Automated Survey). Examples of stars whose light curves allow for trivial classification by the human eye as well as those that require a deeper investigation are discussed.
Contributions of the AAVSO to Year 1 of TESS
Dr. Dennis Conti and Dr. Stella Kafka (AAVSO)
With its well-known legacy and contributions in the area of variable star observing, the AAVSO added in early 1996 an additional focus, that of exoplanet observing. This was done in recognition of the valuable data such amateur astronomers were providing in helping to candidate exoplanets, as well as in the refinement of the ephemerides of known exoplanets. An AAVSO Exoplanet Section was thus established at that time to provide a “home” for such observers where they could be trained in “best practices,” share ideas, and foster communication with the professional community. Over 125 AAVSO members have since completed an Exoplanet Observing Course that covers such best practices, as well as an introduction to the AstroImageJ (AIJ) software.
When TESS began its science operation this past year, a cadre of AAVSO members were then well-trained to participate in TESS’ Follow-up Program (TFOP) Subgroup-1 (SG1), the “Seeing Limited Subgroup.” With SG1’s primary objective being to help in the confirmation of candidate exoplanets, especially by ruling out false positives, AAVSO members have and continue to contribute to this objective. This poster depicts where in the TESS pipeline these observations are made, as well as examples of some of the methods used to identify true exoplanet transits from false positives.
Because systems such as near-by eclipsing binaries (NEBs) can contaminate TESS’ relatively large aperture, a means was needed to reliably eliminate stars near a TESS target that, when blended with the target, could mimic an exoplanet transit. For example, it was found that for some targets, there could potentially be hundreds of near-by stars that needed to be cleared as potential false positives. In order to automate what was a manual process that could take an hour or more and to provide a more comprehensive analysis using Gaia’s Data Release 2 data, the AAVSO liaison to SG1, Dennis Conti, developed an add-on to AIJ that completed this evaluation in minutes. This poster then also displays this automated “NEB clearing” process.
The Project PHaEDRA Collection: An Anchor to Connect Modern Science With Historical Data
Peggy Wargelin, Wolbach Library, Harvard-Smithsonian Center for Astrophysics
Project PHaEDRA (Preserving Harvard’s Early Data and Research in Astronomy) is an initiative by the Wolbach Library, in collaboration with many partners, to catalog, digitize, transcribe, and enrich the metadata of over 2500 logbooks and notebooks produced by the Harvard Computers and early Harvard astronomers. Our goal is to ensure that this remarkable set of items, created by a remarkable group of people, is as accessible and useful as possible. We are working with the Smithsonian Transcription Center to transcribe the PHaEDRA collection. The transcription markup will allow the collection to be full-text searchable on the NASA Astrophysics Data System, and for the notebooks to eventually be linked to their original source material: 500,000 glass plate photographs representing the first ever picture of the visible universe. These glass plate photos are currently being digitized through a project called DASCH: Digital Access to a Sky Century at Harvard. DASCH will enable scientists to produce full photometry results for the entire sky from over 100 years of observations. This will allow researchers in Time Domain Astrophysics to better understand how the Universe is evolving.
Physical conservation of the Project PHaEDRA collection is being generously supported by the Smithsonian Women’s Committee.