DASCH: Digital Access to a Sky Century @ Harvard
A New Look at the Temporal Universe

DASCH Lightcurve Access

Enter one or more object identifiers in the text box below (one per line) and press Search to obtain the lightcurve query results in a separate window.

N >= d <= arcsec

Reference catalog: NOTE: APASS is once more the default.


Before using the DASCH lightcurves, familiarize yourself with the Known Issues that affect the data.

Object identifiers can be:

  • SIMBAD object name:
    • E.g.: V* XX Dor
  • J2000 right ascension and declination:
    • Decimal degrees, e.g.: 5.45 -81.5
    • Sexagesimal with colons, e.g.: 5:26:50 -81:35:12
    • Sexagesimal with spaces, e.g.: 8 41 43.8 +19 43 33.5 (declination sign is mandatory)
  • APASS Catalog ID if using that reference catalog:
    • E.g.: APASS_J115140.7+020334
  • DASCH object ID (for uncatalogued transients):
    • E.g.: DASCH_J123349.2-113822

Search results will only display catalog entries with at least N detections and positions within d arcsec of the query position(s).

Reference catalog: DASCH measurements are matched to and photometrically calibrated against multiple “reference catalogs”, forming distinct lightcurve databases. APASS use B-band magnitudes and provides the best long-term stability. ATLAS has superior astrometry, but is subject to false long-term trends due to its use of g-band magnitudes. Other catalogs are not maintained or supported and should only be used in special circumstances. Use APASS unless you know that the spurious features in the ATLAS data will not affect your science. See the DRnext description for more information.

Because the DASCH lightcurves are pre-compiled through these catalog matches, it is not possible to use this interface to obtain lightcurves for arbitrary sky positions.