ROSATLOG is made by cross-correlating ROSAT observation records with the short-term timeline and contains information about all pointings executed by the satellite during the performance verification (PV) and AO phases. For each observation, details are given concerning target name and coordinates, pointing start and stop times, PI name and country, ROSAT Observation Request sequence number, and more.
ROSATLOG is based on the short-term timelines and observation records generated at the German ROSAT Science Data Center at the Max Planck Institute for Extraterrestrial Physics (MPE) and sent to the ROSAT Guest Observer Facility at Goddard Space Flight Center (GSFC).
Each observation listed in the MPE ASCII files has a ROSAT Observation Request (ROR) sequence number associated with it. Using this sequence number, the observation is matched with the corresponding entry in the ROSAT short-term timeline. (The short-term timeline is also generated by MPE, approximately one week in advance of observations. It is available online within the HEASARC database system, as a database called ROSSTL.) Information such as PI name, country, target name and number, primary instrument, solar angle, time constraints, etc., is then extracted from the timeline and put into the ROSATLOG database. (NOTE: Typing the BROWSE command `lparm` will display all the ROSATLOG parameter names and one-line descriptions to the screen. Those parameters with an asterisk at the beginning of their descriptions are parameters whose values come from the ROSAT short-term timeline; parameters without asterisks contain values extracted from the MPE ASCII files.)
Certain ROSATLOG entries may have parameter fields which contain `??`, `UNKNOWN`, or are blank. In these cases, either the ROR was not found in the short-term timeline or the ROR was found but the completed observation could not be matched with one of the planned observations listed in the short-term timeline.
Despite efforts to make ROSATLOG a complete and accurate record of ROSAT pointings, some errors may still appear; thus ROSATLOG should be used only as a basic guide to what pointings have been executed. ROSATLOG shows in which direction ROSAT pointed and at what time. HOWEVER, it does NOT reflect problems which may have occurred during the pointing and which can result in the total exposure time being much less than the duration of the pointing.
PLEASE NOTE: The `duration` shown here indicates only the length of time that the telescope pointed in a certain direction; it is NOT a total observation time. Operational or other problems may have occurred during the pointing which would cause the total observation time to be less than the `duration` given here.
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