4.2 Target Identification

4.2.1 Target Number [Target_Number]

4.2.2 Target Name [Target_Name]

4.2.3 Target Description [Description]

The following information is required to identify and classify each target.

4.2.1 Target Number [Target_Number]

Each target in your program will be assigned its own unique number (which can be changed by the user) by APT (they are base 10 and go from 1 to 999). Target numbers must be positive, monotonically increasing integers. You should define a different target whenever a different target position or timing description is required. For example, separate targets should be defined if you plan to take spectra of several different surface features on a planet, or if you plan to observe the same feature with different timing constraints.

4.2.2 Target Name [Target_Name]

The name is used to identify a target; all target names within a proposal must be unique. The target name can be selected from the STScI list of standard targets (see Table 4.1; explanations of “Level 1” and “Level 2” are given below), or a name can be defined by the GO. The use of standard names is encouraged whenever possible.

The following conventions should be followed in naming targets:

•	The length of a target name can be anywhere from 2 to 31 characters.

•	No blanks are permitted in target names. A hyphen should replace blanks that would normally be used to separate fields (e.g. IO-TORUS, COMET-BRADFIELD-1979X).

•	Only letters and numerals are allowed in target names; punctuation (other than hyphens and + or –) is not permitted.

•	Construct target names so they make sense for your observing program. For example, if your program consisted of consecutive observations of three surface features on Mars, then three appropriate target names might be: MARS-FEATURE1, MARS-FEATURE2, and MARS-FEATURE3.

Do not use just a standard name for a target when a specific portion of a body is being observed. For example, do not use “Saturn” as the target name for a feature or specific location that is defined relative to the position of Saturn as a standard target because this is confusing for the software that computes the positions of moving targets.

 

Table 4.1: Solar System Standard Targets 

Level 1	Level 2
Sun
Mercury
Venus
Earth	Moon	Hubble
Mars	Phobos	Deimos
Jupiter	Io	Europa	Ganymede
	Callisto	Amalthea	Himalia
	Elara	Pasiphae	Sinope
	Lysithea	Carme	Ananke
	Leda	Thebe	Adrastea
	Metis	Callirrhoe	Themisto
	Taygete	Chaldene	Harpalyke
	Kalyke	Iocaste	Erinome
	Isonoe	Praxidike	Autonoe
	Thyone	Hermippe	Aitne
	Eurydome	Euanthe	Euporie
	Orthosie	Sponde	Kale
	Megaclite	Pasithee	Hegemone
	Mneme	Aoede	Thelxinoe
	Arche	Kallichore	Helike
	Carpo	Eukelade	Cyllene
	Kore	Herse
Saturn	Mimas	Enceladus	Tethys
	Dione	Rhea	Titan
	Hyperion	Iapetus	Phoebe
	Janus	Epimetheus	Helene
	Telesto	Calypso	Atlas
	Prometheus	Pandora	Pan
	Paaliaq	Tarvos	Ijiraq
	Suttungr	Kiviuq	Mundilfari
	Albiorix	Skathi	Erriapus
	Siarnaq	Thrymr	Ymir
	Narvi	Methone	Pallene
	Polydeuces	Daphnis	Aegir
	Bebhionn	Bergelmir	Bestla
	Farbauti	Fenrir	Fornjot
	Hati	Hyrrokkin	Kari
	Loge	Skoll	Surtur
	Anthe	Jarnsaxa	Greip
	Tarqeq	Aegaeon
Uranus	Ariel	Umbriel	Titania
	Oberon	Miranda	Cordelia
	Ophelia	Bianca	Cressida
	Desdemona	Juliet	Portia
	Rosalind	Belinda	Puck
	Caliban	Sycorax	Prospero
	Setebos	Stephano	Trinculo
	Francisco	Margaret	Ferdinand
	Perdita	Mab	Cupid
Neptune	Triton	Nereid	Naiad
	Thalassa	Despina	Galatea
	Larissa	Proteus	Halimede
	Psamathe	Sao	Laomedeia
	Neso
Pluto	Charon	Nix	Hydra
Ceres
Haumea	Hiiaka	Namaka
Eris	Dysnomia
Makemake

If you are uncertain whether or not your target can be referenced by name, contact your Program Coordinator for guidance.

4.2.3 Target Description [Description]

The target description is used to sort the solar system targets by class and will be useful to archival researchers. The first word in any target description must be one of the keywords listed below. The keyword is then followed with text that depends on the target class as described below.

Table 4.2: Target Description Keywords 

Keyword	Description
PLANET	If the target is the center of a planet, enter PLANET followed by its name (e.g., PLANET JUPITER, PLANET SATURN).
DWARFPLANET	If the target is the center of a dwarf planet, enter DWARF-PLANET followed by its name(e.g., DWARF-PLANET CERES)
SATELLITE	If the target is the center of the satellite of a planet, enter SATELLITE followed by the satellite name (e.g., SATELLITE GANYMEDE, SATELLITE 1980S27)
COMET	If the target is the nucleus of a comet, enter COMET followed by its common name or catalog designation (e.g., COMET HALLEY, COMET 1979X)
ASTEROID	If the target is the center of an asteroid, enter ASTEROID followed by its common name or its catalog number (e.g., ASTEROID CERES, ASTEROID 452)
FEATURE	If the target is a surface feature, enter FEATURE followed by the name of the parent body (e.g., FEATURE JUPITER, FEATURE IO)
OFFSET	If the target is an offset position with respect to a solar system body (but not a feature on its surface), enter OFFSET followed by the name of the parent (reference) object (e.g., OFFSET COMET HALLEY, OFFSET JUPITER)
RING	If the target is in a ring, enter RING followed by the name of the parent object (e.g., RING JUPITER, RING SATURN)
TORUS	If the target is a plasma torus, enter TORUS followed by the name of the parent object (e.g., TORUS JUPITER)
OTHER	If your target cannot be classified under any of the categories above, then enter OTHER followed by some description of the type of observation planned (e.g., ASTROMETRIC REFERENCE, INTERPLANETARY MEDIUM, ZODIACAL LIGHT)