AAS 198th Meeting, June 2001
Session 3. Analysis, Data and Distances
Display, Monday, June 4, 2001, 9:20am-6:30pm, Exhibit Hall

[Previous] | [Session 3] | [Next]

[3.04] How Long Does It Take to Get Your HST Data?

S.B. Parsons, R. Arquilla, D. Christian, T.A. Ellis, D. Fraquelli, E. Giovane, F. Hamilton, A. Holm, D. Kenny, M. Kochte, J.F. Scott (CSC/STScI)

The processing of HST telemetry into files which may be displayed and analyzed is performed by Observation Processing and Uplink Services Branch staff at STScI, running the `OPUS' software system developed by members of the Data Systems Team. The unprocessed telemetry files and the processed FITS files are passed to the Data Archive and Distribution Service (DADS) operated by Archive Branch staff.

The one performance goal which has been tracked since Launch is that 98% of observations should be processed within 2 days of receipt; actual achievement is close at 95%. Daily metrics reports from a complex set of database queries are now analyzed to pinpoint delays in data processing, archiving, and delivery. On AVERAGE: science telemetry is received at STScI about 12 hours After Execution (AE) of an exposure onboard HST. Files are ingested into DADS about 1.0-1.5 days AE. Engineering telemetry is processed into data products for FGS astrometry observations and into `jitter files' for all observations about 3.0-3.5 days AE. With no significant anomalies, then by 4 days AE a user may start to look for both the observation data and the jitter file indicators of observation success. In case of anomalous engineering indicators, a human assessment is performed about 4.5 days AE and the results are captured in QUAL* keywords accessible by StarView from the DADS catalog. The PDF `paper products', made after all observation data for a proposal are complete for a given week, are available about 9 days AE.

User requests for data are now serviced by On-The-Fly-Reprocessing of the telemetry file to have the most correct headers and calibrations available, and are typically processed 6-8 hours after receipt (median), depending upon system up-time and bandwidth. Numerous factors such as system upgrades, or hardware glitches on a Friday evening not detected and rectified until Monday, can lengthen any or all of the above times!

[Previous] | [Session 3] | [Next]