Data Set Overview : This dataset contains the results obtained from the Dust Impact Detection System (DIDSY) flown aboard the GIOTTO spacecraft during its extended mission to Comet P/Grigg-Skjellerup in 1992. The measurements and analysis of the three impacts detected during close approach are contained in text files. Calibration tables for the sensors are included in this dataset.   Parameters : The timing and masses of the impacting meteroid are tabulated within the DOCUMENT file, 'didtext.doc'.   Processing : See the 'didtext.doc' file for details of the data processing and analysis.  For PDS ingest, the shield map files were each pulled out of the original text file and formatted as separate PDS TABLE files, each with its own label.   Data : The data set consists of four files:  didtext.doc An early draft of a paper published in April 1993 as a Letter to Nature. This file provides a description of the experiment, presents the results and includes a discussion of the data analysis did2map.tab These files contain the bumper shield maps for did3map.tab each of the three sensors active during the did4map.tab flyby. The maps indicate relative sensitivity of each area on the shield compared to a direct impact on the sensor.  Ancillary Data : There is no ancillary data to this data set.  Coordinate System : See the analysis section of the 'didtext.doc' file for a description of the geometry of the impacts.  Software : Not applicable.  Media/Format : These data are available as part of the Giotto Extended Mission CDROM.

Confidence Level Overview : See the 'didtext.doc' file for a discussion of the analysis procedure as well as the effects of the previous encounter with Comet P/Halley on the DIDSY sensitivity at P/Grigg-Skjellerup.  Review : These data were reviewed for ingest into the PDS permanent archives in December 1995.  Data Coverage and Quality : See the 'didtext.doc' file.  Limitations : See the 'didtext.doc' file.