Targets ======= .. toctree:: :maxdepth: 2 :caption: Table of Contents :hidden: Custom Target fields Target matching Target table Select targets for facility <../observing/selecting_targets_for_facility> The ``Target``, along with the associated ``TargetList``, ``TargetExtra``, and ``TargetName``, are the core models of the TOM Toolkit. The ``Target`` defines the concept of an astronomical target through a number of parameters. The ``Target`` object is then used throughout the TOM to reference all the information a user or app needs to know about a target. As astrophysical objects are often identified in multiple catalogs, each ``Target`` is associated with one or more ``TargetName``. More information on Targets can be found using the following pages: :doc:`Target Models ` - Take a look at the available properties for a ``Target`` and its associated models. :doc:`Target Views ` - Familiarize yourself with the available Target Views. :doc:`Target Lists ` - Check out the functions for operating on Target Lists/Target Groups. Customizing the BaseTarget -------------------------- Although almost all astrophysical targets share some descriptive parameters - such as RA, Dec or orbital parameters - the Toolkit recognizes that each science case has a specific set of relevant parameters. For example, for some science goals, a ``Target`` may have a measured period, while this may not be appropriate for an aperiodic object. For this reason, the Toolkit provides a ``BaseTarget`` class which supports both sidereal and non-sidereal celestial objects. By default, this is used to create the ``Target`` model when a TOM is created. However, this class is designed to be extended by users to add fields relevant to their science. See :doc:`Adding Custom Target Fields ` to learn how to add custom fields to your TOM Targets. Crossmatching Targets --------------------- It is often useful to compare a target with those already in the TOM, especially to avoid duplicating targets. By default, matching is performed on ``TargetName``, but the TOM includes functions to match on position as well. If you need to compare targets using different parameters, :doc:`Customizing a Target Matcher ` describes how to add a custom match function. TargetLists ----------- By default, all targets in the TOM are treated as a single collection, which can be viewed as a table and on an interactive skymap by navigating to the Targets view. The columns presented in the target list table can be customized - see :doc:`Customizing the Target List Table ` for more information. Targets can be collected into user-created lists for convenience. Target and TargetList Sharing ----------------------------- Individual targets and their associated data can be shared directly with another TOM, with the TOM administrator's permission. Sets of targets can also be shared. See :doc:`TOM Direct Sharing ` to learn how to configure the TOMs to allow this.