Target Descriptions

The Fixed Targets form is used to specify fixed targets in some JWST observations. This article provides a list of target descriptions for the Astronomer’s Proposal Tool (APT).

Target Descriptions

Table 1. Descriptive Keywords for Clusters of Galaxies 

Descriptive Keywords for Clusters of Galaxies
Abell clustersIntergalactic voids
Brightest cluster galaxiesIntracluster medium
Coma ClusterLarge Magellanic Cloud
Einstein ringsMagellanic Stream
Galaxy collisionsPerseus Cluster
Galaxy groupsPoor clusters
Galaxy mergersRich clusters
Galaxy tidesSmall Magellanic Cloud
Galaxy voidsSuperclusters
Hickson compact groupVirgo Cluster
High-redshift clustersVirgo Supercluster
Interacting galaxies

Table 2. Descriptive Keywords for Galaxy 

Descriptive Keywords for Galaxy

Active galactic nuclei

E+A galaxies

Interacting galaxies

Radio jets

Active galaxies

Einstein rings

Irregular galaxies

Radio lobes

Amorphous Irregular Galaxies

Elliptical galaxies

LINER galaxies

Radio loud quasars

Astrophysical masers

Emission line galaxies

Lenticular galaxies

Radio plumes

BL Lacertae objects

Field galaxies

Low Surface Brightness galaxies

Radio quiet quasars

Barred spiral galaxies

Galactic accretion disks

Lyman-alpha galaxies

Relativistic disks


Galaxy bulges

Lyman-break galaxies

Relativistic jets

Blue compact dwarf galaxies

Galaxy circumnuclear disk

Magellanic Clouds

Ring galaxies

Brightest cluster galaxies

Galaxy disks

Magellanic Irregular Galaxies

Seyfert galaxies

Broad-absorption line quasar

Galaxy halos

Markarian galaxies

Spiral arms

Compact dwarf galaxy

Galaxy jets

Nucleated dwarf galaxies

Spiral galaxies

Compact galaxies

Galaxy nuclei

Polar jets

Starburst galaxies

D galaxies

Galaxy voids

Primordial galaxies

Tidal tails

Disk galaxies

Giant elliptical galaxies


Ultracompact dwarf galaxies

Double quasars

Giant galaxies

Quasar-galaxy pairs

Ultraluminous infrared galaxies

Dwarf elliptical galaxies

Haro galaxies


X-ray quasars

Dwarf galaxies

High-redshift galaxies

Radio cores

cD galaxies

Dwarf irregular galaxies

Infrared excess galaxies

Radio galaxies

Dwarf spheroidal galaxies

Infrared galaxies

Radio hot spots

Table 3. Descriptive Keywords for ISM 

Descriptive Keywords for ISM

Astrophysical masers

Gaseous nebulae

Interstellar dust

Protoplanetary nebulae


H I regions

Interstellar magnetic fields


Bipolar nebulae

H II regions

Interstellar molecules

Reflection nebulae

Bright nebulae

Herbig Ae/Be stars

Intracluster medium

Ring nebulae

Cocoon stars

Herbig-Haro objects

Lyman limit systems

Silicon monoxide masers

Cold neutral medium

High-velocity clouds

Lyman-alpha forest clouds

Stellar jets

Cometary nebulae

Hot intergalactic medium

Magellanic Stream

Stellar wind bubbles

Compact nebulae

Hot ionized medium


Stellar winds

Cool intergalactic medium

Hydroxyl masers

Metal line absorbers


Damped Lyman-alpha systems

Intercloud medium

Molecular clouds

Supernova remnants

Dark interstellar clouds

Intergalactic clouds

Molecular gas

Supernova remnants

Dark matter

Intergalactic dust clouds


Tidal tails

Dense interstellar clouds

Intergalactic filaments

Neutral hydrogen clouds

Warm ionized medium

Diffuse interstellar clouds

Intergalactic gas

Photodissociation regions

Warm neutral medium

Diffuse nebulae

Intergalactic medium

Planetary nebulae

Warm-hot intergalactic medium

Dust nebulae

Intergalactic voids

Plasma clouds

Emission nebulae

Intermediate-velocity clouds

Pre-main sequence stars

Evaporating gaseous globules

Interstellar absorption

Pre-solar nebulae

Filamentary nebulae

Interstellar clouds


Table 4. Descriptive Keywords for Star 

Descriptive Keywords for Stars

53 Persei stars

DQ stars

Interacting binary stars


A dwarfs

DZ stars

Irregular variable stars


A giants

Debris disks

K dwarfs

Pulsating variable stars

A stars

Delta Delphini stars

K giants

RR Lyrae variable stars

A subdwarfs

Delta cephei

K stars

RS Canum Venaticorum variables

A subgiants

Detached binary stars

K subdwarfs

Recurrent novae

A supergiants

Disk stars

K subgiants

Red giants

AM Herculis stars

Double-mode Cepheids

K supergiants

Red stragglers

Asymptotic giant branch

Dust shell

L dwarfs

Red supergiants

B dwarfs

Dwarf novae

L subdwarfs

S stars

B giants

Eclipsing binary stars

Late-type giants

Semi-detached binary stars

B stars


Long period variables

Semiregular variables

B subdwarfs

Ellipsoidal variable stars

Low-mass X-ray binary stars

Shell stars

B subgiants

Emission line stars

Luminous blue variables

Slow irregular variables

B supergiants

Eruptive variables

M dwarfs

Stellar winds

Barium stars

Eta Carinae stars

M giants

Substellar companions

Beta Lyrae stars


M stars


Binary pulsars

Exoplanet Systems

M subdwarfs

Symbiotic binary stars

Black holes


M subgiants

T Tauri stars

Blue stragglers

F dwarfs

M supergiants

T dwarfs

Bok globules

F giants

Magnetic stars

T subdwarfs

Brown dwarfs

F stars

Magnetic variable stars

Type II supernovae

Carbon stars

F subdwarfs

Mira variables

Type Ia supernovae

Cataclysmic variable stars

F subgiants

Multiple stars

Type Ib supernovae


F supergiants

Neutron stars

UV transients

Circumstellar clouds

FU Orionis stars

Nova-like variable stars

W Ursae Majoris variable stars

Circumstellar disks

Flare stars


WC stars

Circumstellar dust

Flash stars

O dwarfs

WN stars

Circumstellar gas

G dwarfs

O giants

White dwarfs

Circumstellar masers

G giants

O stars

Wolf-Rayet stars

Circumstellar matter

G stars

O subdwarfs

X-ray binary stars

Classical novae

G subdwarfs

O supergiants

X-ray bursters

Cocoon stars

G subgiants

OB stars

X-ray novae

Cometary nebulae

G supergiants

PG 1159 stars

X-ray stars

Compact binary stars

Gamma Ray bursters

Periodic variable stars

X-ray transients

Compact binary systems

Gamma Ray transients

Planetary nebulae nuclei

Y dwarfs

Companion stars

Giant stars

Population I stars

Yellow stragglers

Contact binary stars

H-alpha stars

Population II stars

Young disk Cepheids

DA stars

Heavy metal stars

Population III stars

Young stellar objects

DB stars

Herbig Ae/Be stars

Post-asymptotic giant branch

ZZ Ceti stars

DC stars

Herbig-Haro objects

Pre-main sequence stars

DO stars

High-mass X-ray binary stars


DQ Herculis stars

Horizontal branch stars

Protoplanetary disks

Table 5. Descriptive Keywords for Stellar Cluster 

Descriptive Keywords for Stellar Cluster
Globular star clustersProtoclusters
Moving clustersR associations
O associationsStellar associations
O clustersT associations
OB associationsYoung associations
Open star clustersYoung star clusters

Table 6. Descriptive Keywords for Unidentified 

Descriptive Keywords for Unidentified
Blank fieldUltraviolet sources
High latitude fieldVariable radiation sources
Infrared sourcesVisible sources
Parallel fieldX-ray sources
Radio sources

Table 7. Descriptive Keywords for Calibration 

Descriptive Keywords for Calibration
Aperture locationPhotometric

A stars

AstrometricPoint spread functionBinary stars
CoronagraphicPointing and jitter testEmission nebulae
Detector linearity testSpectrophotometricEmission line stars
External flat fieldStray light testG stars
Focus testTarget acquisition testOpen star clusters
Line spread functionTelescope/sky backgroundPlanetary nebulae
Persistence testWavelengthWhite dwarfs

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