The ESO Very Large Telescope (VLT) is a set of 4 8.2m ground based telescopes that are currently being constructed in northern Chile. The Space Science Telescope Institute (STScI) is under contract to provide both long range planning short term scheduling software. Note that first light was reached 25-26 May 1998. Refer to the ESO press release for more information.
STScI is developing a long range scheduling engine that will be used to create 6 month plans. The long range plan will not be scheduling observations, but blocks of observing time (ie., classical time, service time, or reserved time). To support a long range creation, the software will have to support astronomical event calculation (ie., moon phase preference, night preference, RA ranges, etc), both absolute (ie., do this observation at time x) and relative (ie., A after B by x days; C, D, E at same time on different telescopes). There are numerous automatic planning algorithms available as well as the ability to manually plan observations.
Short Term Schedules are generated for service blocks only. A short term schedule consists of time ordered observations to perform during the evening. A short term schedule may be generated numerous times a night depending on the current seeing conditions. The short term software supports astronominical event calculation (ie., sun, moon, sky sensitivity, airmass, distance from zenith, etc), absolute and relative constraints, and both automatic and manual scheduling.
STScI is also developing a Graphical Scheduling Widget to display the scheduling timeline and scheduled activities. This widget is interactive and will provide capabilities for mousing objects and clicking on portions of the screen to get more information. A prototype widget is shown below
Our paper at the ADASS-97 conference describes how Spike is being used for short term scheduling at the VLT.
VLT Scheduling Widget