Getting Started

The GLO experiment has collected a great deal of data. The data is being organized systematically which is a slow process. However, small workable data sets can be provided to initiate analysis and establish a familiarity with the data format.

We have organized a search process which will allow data to be selected on the basis of several input parameters. The search is begun by the user specifying data parameters using the data in the User Calibrated Ancillary Tape (UCAT) file. The UCAT contains many parameters pertaining to the observations such as orbiter altitude, latitude and longitude, scan platform azimuth and elevation, tangent point latitude and longitude of the field of view, tangent point altitude, solar zenith angle, etc. These parameters are tabulated for every spectrum or image. A subset is available in the UCAT file for every minute the instrument was "on" during the flight. By entering the range of the parameters of interest, a file will be returned containing the periods during which the conditions were satisfied. At this time the UCAT file is continuous throughout the flight even if the experement was not recording data. As the data is processed, periods when there was no data will be edited out of the UCAT file.

The next step is to go to the GLOView program for the flight of interest. The program can be downloaded and operated as indicated in the document file. When the mission elapsed time (MET) is input to GLOView, the program shows the attitude of the Shuttle with respect to Earth and the pointing direction and orientation of the spectrograph slit and imagers. When you have identified the data set you wish to examine, contact the data center with your request.

The data is in FITS format. It can be reviewed most easily by use of our data processing program SIBYL. A version of SIBYL is available for downloading. The program requires a modern DOS-based PC. It is a command-driven program. Some help may be required to get it running. A contact person can be assigned by making an e-mail request to Dr. A. L. Broadfoot.

o Last Updated: 18 January, 1996

This page is maintained by:
Jesus A. Ramirez