TAO can be used in a wide variety of observing programs, such as

• Astrometry of solar system objects (including confirmation of new NEO candidates listed on the NEO Confirmation Page and follow-up and recovery of minor planets and comets)
• Searches for new solar system objects
• Photometry of minor planets, comets, variable stars, etc.
• Supernova searches
• Follow-up of Gamma-Ray Bursts (GRBs)

TAO can be used (either in its standard form or in custom-modified versions) with automated telescope/CCD camera systems which can receive commands either from scripts or through text files. It is especially useful to managers of automated telescopes, including those who may need an efficient way to share telescope time among a number of observing programs, each having their own observing preferences and constraints.

TAO consists of three main components:

• A telescope scheduler. This program allocates telescope time to the various targets which the users of the telescope wish to observe, in such a way as to satisfy a number of observational constraints (altitude and hour angle limits, horizon obstructions, time interval between images of a given target, distance from the moon, etc.). The complex decisions and numerous possibilities involved in planning a long automated observing run are analyzed by the scheduler, which uses physical information about the observing station, telescope, dome, CCD camera, etc., to simulate all actions to be performed by the telescope, camera, and other equipment with a timing accuracy of the order of one minute throughout a whole night of observations. The output of the scheduler consists of a detailed sequence of actions to be performed by the telescope during the night, and the times at which these actions will be performed. This sequence of actions is also written to text files in a format which can be understood by the telescope control system. Such a detailed schedule allows the telescope administrator to precisely control the amount of telescope time allocated to different observing programs. It also allows the accurate scheduling, before the start of a night's observing run, of observations of targets which only become visible for a very short time before the start of morning twilight (e.g., objects leaving solar conjunction). For such targets, timing is critical: if observations are made a little too early, the targets will not have risen to a sufficient altitude above the horizon, while if they are made a little too late the images will be spoiled by twilight.

• Tools for creating and maintaining updated target databases. TAO stores information on fixed targets (stars, galaxies, minor planet search fields, etc.) and moving targets (minor planets, comets, etc.) on two separate databases. Fixed targets may be imported from text files containing target designations, coordinates, and (optionally) magnitudes in a variety of formats. The moving object database may be kept up-to-date by periodically running a script which automatically downloads ephemeris for unusual minor planets (including NEOs, TNOs, etc.) and comets which are currently observable. This script downloads updated ephemeris whenever an object's orbit is updated by the Minor Planet Center (MPC), and automatically adds newly discovered unusual minor planets and comets to the moving object database. It can also be used for adding any minor planet or comet of interest to the moving object database. Another script is available for automatic monitoring of the NEO Confirmation Page (NEOCP), including ephemeris download and automated analysis of the ephemeris uncertainty information provided on the NEOCP. This script makes it possible to quickly schedule a mosaic of CCD fields which covers the uncertainty region of a given NEOCP object. Ephemerides for new objects for which only the discovery astrometry is available may also be easily added to the moving object database with the help of another script. A program is provided for generating filtered summary tables of targets which are observable on a given night, including parameters such as magnitude, elongation, motion rate, galactic latitude, moon distance, etc. These tables are helpful in the process of selecting targets of interest to be submitted to the scheduler.

• An image acquisition script (the MU script). In its standard form, this script may be executed under the ACP observatory control software (see the system requirements page for more details), and will automate dusk-to-dawn observatory operations without user intervention (other than uploading a target list generated by the TAO scheduler). The MU script will start cooling the CCD detector some time before sunset, open the dome at sunset, take calibration files (including flat fields in various filters), start observations at scheduled times, focus the telescope several times along the night, end the observations at the appropriate time, close the dome, produce detailed logs and accounting reports, and distribute all images in real-time to appropriate directories on an FTP server (allowing real-time image download by various users). This script may be started from a remote location by using either the ACP web interface, or remote-control software such as pcAnywhere or TightVNC. Custom versions of the MU script can often be written for use with automated telescopes which cannot be controled by ACP.