"Long and Short Term Scheduling Tools in ESO"

Gino Giannone (European Southern Observatory), 
Alberto M. Chavan (ESO), 
David Silva (ESO), 
Anthony P. Krueger (Space Telescope Science Institute), 
Glenn E. Miller (STScI)

Abstract

The cost of the telescopes and in particular of an 8-meter class
telescope like the Very Large Telescope makes it necessary to maximize
the efficiency of telescope operations. The science productivity can
be improved with the support of scheduling tools.  We developed two
software tools based on STScI SPIKE engine, which was originally
written for the use of the Hubble Space Telescope.  This software was
adapted to support the constraints of a ground based telescope.  The
Long Term Scheduler (LTS) is a software tool used twice a year to
schedule all the Proposals submitted to ESO for a six month time
range. It is a Decision Support System that helps the user best fit
the astronomical constraints of the Proposals, like target visibility,
required moon phase, links among different Proposals and critical
times.  A prototype of the LTS was already used for "ESO Period 64" to
schedule 2 out of the 7 ESO telescopes.  The Short Term Scheduler
(STS) is used to schedule the observations of "service mode" periods
for the VLT on a night basis.  The STS is useful to react quickly to
changing weather conditions.  We report in the paper the first users'
experience with these scheduling tools.