low##power##radio##loud##agn##active##galactic##nucleus##nuclei##lowpower##radioloud##galaxy
Low-Power Radio-loud AGN
Maser Emission
emission##maser##process##processes
super##massive##supermassive##black##hole##blackhole##holes#blackholes##smbh
Supermassive Black Hole
GammaRays
gamma##rays##ray
Gamma Rays
gamma radiation
Gamma rays
Gamma-ray
GAMMA RAYS
equivalent##width
EquivalentWidths
Equivalent Width
EQUIVALENT WIDTHS
*iN
Stellar Object in Nebula
stellar##object##star##in##nebula##stars##objects
*inNeb
optical
optical
Optical
White dwarf with metal lines
electron##temperature
Electron Temperature
dwarf##dwarves##A##star##stars##A-type##A
A DWARF STARS
ADwarfStars
Range allowing the description of the existence of a (noticeable) continuum for a given object
ContinuousSpectra
CONTINUOUS SPECTRA
Equivalent widths
Multiplet
ContinuumRadiation
Balmer lines
Continuum
Radio continuum
Continua
Line Profiles
CONTINUUM RADIATION
continuum
Radio Lines
CONTINUA
MagneticFields
magnetic##field
MAGNETIC FIELDS
magnetic Field
Magnetic fields
Magnetic_fields
dwarf##barred##spiral##galaxy##gal##galaxies##g
Dwarf Barred Spiral Galaxy
BCG
BlueCompG
blue##compact##galaxy##gal##galaxies##g
Blue Compact Galaxy
white dwarfs with carbon lines
galactic##galaxy##morphology##ring
PulsV*semi-reg
sr*
semi##regular##semiregular##pulsating##star##stars##reg
SR
Semi-regular pulsating star
Semi-regular Pulsating Star
neutral##gas##gases
Neutral Gas
NEUTRAL GASES
NeutralGases
MoC
GiantMolecularClouds
DarkNebulae
MolCld
Molecular clouds
MCld
MolecularClouds
DARK NEBULAE
molecular##cloud##clouds
MOLECULAR CLOUDS
Molecular Cloud
GIANT MOLECULAR CLOUDS
Orion variables. Irregular, eruptive variables connected with bright or dark diffuse nebulae or observed in the regions of these nebulae. Some of them may show cyclic light variations caused by axial rotation. In the Spectrum-Luminosity diagram, they are found in the area of the main sequence and subgiants. They are probably young objects that, during the course of further evolution, will become light-constant stars on the zero-age main sequence (ZAMS). The range of brightness variations may reach several magnitudes.
This type may be divided into the following subtypes:
- Rapid light variations observed (up to 1 mag in 1-10 days),
- Orion variables of early spectral types (B-A or Ae). They are often characterized by occasional abrupt Algol-like fadings (T Ori);
- Orion variables of intermediate and late spectral types, F-M or Fe-Me (BH Cep, AH Ori). F-type stars may show Algol-like fadings; K-M stars may produce flares along with irregular light variations;
- Orion variables of the T Tauri type. Stars are assigned to this type on the basis of the following (purely spectroscopic) criteria: spectral types are in the range Fe-Me. The spectra of most typical stars resemble the spectrum of the solar chromosphere. The feature specific to the type is the presence of the flourescent emission lines Fe II 4046, 4132 A (anomalously intense in the spectra of these stars), emission lines [Si II] and [O I], as well as the absorption line Li I 6707 A. These variables are usually observed only in diffuse nebulae.
- Some Orion variables (YY Ori) show the presence of absorption components on the redward sides of emission lines, indicating the infall of matter toward the stars' surfaces.
IN
orion##variable##star##stars##variables
Orion_V*
ORION POPULATION STARS
Orion Variable Star
Or*
OrionPopulationStars
Variable Star of Orion type
BeStars
Be dwarf stars
herbig stars
be##star##bestar##stars##bestars
Be STARS
Be*
Be Star
GAMMA CASSIOPEIAE STARS
GammaCassiopeiaeStars
Be*
Stars, Be
V
Flux
Flux
FLUX
flux
T
F DWARF STARS
FDwarfStars
NL*
Insufficiently studied objects resembling novae by the characteristics of their light changes or by spectral features. This type includes, in addition to variables showing novalike outbursts, objects with no bursts ever observed; the spectra of novalike variables resemble those of old novae, and small light changes resemble those typical for old novae at minimum light. However, quite often a detailed investigation makes it possible to reclassify some representatives of this highly inhomogeneous group of objects into other types.
NL
novalike##like##nova##object##objects
Nova-like
Nova-like Object
VELOCITY
Space velocities
Velocity
Velocity
velocity
Velocities
Dust
Dust
DUST
dust##dusts
galactic##galaxy##morphology##spiral
S##Sa##Sb##Sc##Sd##Sab##Sbc##Scd##
B GIANT STARS
BGiantStars
IrregularVariableStars
Irregular Variable Star
Stars showing variations of irregular (non-periodic) type. Mostly (?) of eruptive type.
Ir*
Irregular_V*
Variable Star of Irregular type
irregular##variable##star##variables##stars
IRREGULAR VARIABLE STARS
G Giant Star
G GIANT STARS
GGiantStars
g##gtype##giant##giants##star##stars
Any astronomical object
astrobject##astroobject##astronomical##object##astrobjects##astroobjects#objects
Astronomical Object
galactic##galaxy##morphology##dwarf##spiral
chromospheric##activity##chromosphere
Corresponds to an important chromosperic activity, usually a source of emission
Chromospheric Activity
lumx
LumX
Rotation
Rotation Process
ROTATION
rotation##process##processes##rotational
galactic##galaxy##morphology##lenticular
S0##S0a
Red Giant
red##redgiant##giant##redgiants##giants
Emission Nebula
emission##nebula##nebulae##neb
EmissionNebulae
EMISSION NEBULAE
Millimetric/submm sources
Radio(sub-mm)
smm
Sub-millimetric Radio Source
sub##millimetric##submillimetric##radio##source
Galaxy in a Group of Galaxies
GinGroup
Galaxy in Group
group##galaxy##gal##galaxies##in##g
GiG
MillimeterWaves
Radio Millimetric
mm radiation
MILLIMETER RADIATION
Spectra, millimetric/submm
radio##millimetric##mm
MillimeterRadiation
MILLIMETER WAVES
molecules##molecule
MOLECULES
Molecules
Molecules
galactic##galaxy##morphology##giant##elliptical
optical##source
Optical Source
Optical
NIR
Near IR
near##ir##infrared##source
IR<10ยต
Near-IR Source
em##source##electromagnetic##electro##magnetic
EM Source
jet##jets
Jet
JETS
Jets
astrophysical jets
Ring Galaxy
RING GALAXIES
ring##gal##galaxy##galaxies##g
RingGalaxies
Galaxies, ring
Blue Supergiant
blue##super##giant##supergiant##giants##supergiants
Masers
Maser
Maser
maser
Maser
Mas
MASERS
Stars, masers
Masers
High-power Radio-loud AGN
high##power##radio##loud##agn##active##galactic##nucleus##nuclei##highpower##radioloud##galaxy
Flux Ration Radio5Ghz-Optical
flux##ratio##radio5ghz##radio##5Ghx##optical
Power Radio
power##radio
EmissionLineGalaxies
EMISSION LINE GALAXIES
EmG
emission##line##galaxy##gal##galaxies##g
EmG
Emission-line Galaxy
galactic##galaxy##morphology##ring##polar
G##gtype##g-type##type##star##stars##dwarf##dwarves
GDwarfStars
G DWARF STARS
G Dwarf Star
eclipse##beta##lyrae##process##processes##betalyrae
Eclipse of Beta Lyrae Type
SN*
SN
Supernovas
supernova
supernova
Supernova
SUPERNOVAS
SN
Supernovae
SN
SuperNovae
supernova##supernovae##super##nova##novae##sn
FarInfraredRadiation
Far Infrared
Wavelength above 30 microns
far##infrared
FAR INFRARED RADIATION
Stars, flare
Flare Star
FLARE STARS
FlareStars
flare
Flare*
Flare*
Flare Star
Eruptive variables varying in brightness because of flares occurring in their chromospheres and coronae.
Sub-types:
- Orion variables of late (K-M) spectral types
- Eruptive variables of the UV Ceti type, these are K Ve-M Ve stars sometimes displaying flare activity with amplitudes from several tenths of a magnitude up to 6 mag in V. The amplitude is considerably greater in the ultraviolet spectral region. Maximum light is attained in several seconds or dozens of seconds after the beginning of a flare; the star returns to its normal brightness in several minutes or dozens of minutes.
- Flaring Orion variables of spectral types Ke-Me. These are phenomenologically almost identical to UV Cet variables observed in the solar neighborhood. In addition to being related to nebulae, they are normally characterized by being of earlier spectral type and greater luminosity, with slower development of flares (V389 Ori).
- BY Draconis-type (rotating) variables, which are emission-line dwarfs of dKe-dMe spectral type showing quasiperiodic light changes with periods from a fraction of a day to 120 days and amplitudes from several hundredths to 0.5 mag in V. The light variability is caused by axial rotation of a star with a variable degree of nonuniformity of the surface brightness (spots) and chromospheric activity. Some of these stars also show flares similar to those of UV Cet stars, and in those cases they also belong to the latter type and are simultaneously considered eruptive variables.
flare##star##flarestar##stars
Fl*
Morphology
Morphological Feature
Geometry or morphology of astronomical objects (including components which are not astronomical objects)
Morphology
MORPHOLOGY
morphology##morphological##geometry##geometrical##feature##features
SUBMILLIMETER WAVES
radio##sub##millimetric##submillimetric
Spectra, millimetric/submm
Radio Submillimetric
SubmillimeterWaves
GinCl
Galaxy in Cluster
Galaxy in a Cluster of Galaxies
cluster##in##galaxy##gal##galaxies##g
GiC
portion##astroportion##portions##astroportions
Portion of Astronomical Object
Portion of an astronomical object which is not an astronomical object itself
UV
UV Source
UV
UltravioletSources
UV
ultraviolet objects
uv##ultraviolet##ultra##violet##source
Ultraviolet
ULTRAVIOLET SOURCES
mul
A composite object is made of at least two distinct astronomical objects
compound##composite##object
Compound object
multiple_object
2
galactic##galaxy##morphology##barred##spiral
SB##SBa##SBb##SBc##SBd##SBab##SBbc##SBcd##SB0##SB0a
small##separation##lobes##radio
Classical Cepheid (delta Cep type)
deltaCep
delta##cepheid##classical##cep##cephei##cepheids##ceps##variable##variables
classical cepheids
Classical Cepheid
delta cephei stars
These are the classical cepheids, or Delta Cep-type variables.
Comparatively young objects that have left the main sequence and evolved into the instability strip of the Hertzsprung-Russell (H-R) diagram, they obey the well-known Cepheid period-luminosity relation and belong to the young disk population. Delta Cep stars are present in open clusters. They display a certain relation between the shapes of their light curves and their periods.
Sub-type:
- These are Delta Cep variables having light amplitudes <0.5 mag in V (<0.7 mag in B) and almost symmetrical light curves (M-m approx. 0.4 - 0.5 periods); as a rule, their periods do not exceed 7 days. They are probably first-overtone pulsators and/or are in the first transition across the instability strip after leaving the main sequence (SU Cas).
Traditionally, both Delta Cep and W Vir stars are quite often called Cepheids because it is often impossible to discriminate between them on the basis of the light curves for periods in the range 3 - 10 days. However, these are distinct groups of entirely different objects in different evolutionary stages. One of the significant spectral differences between W Vir stars and Cepheids is the presence, during a certain phase interval, of hydrogen-line emission in the former and of Ca II H and K emission in the latter.
DCEP
cC*
A high-mass X-ray binary (HMXB) is a binary star system where one of the components is a neutron star or a black hole. The other component is a massive star, usually a Be star or a blue supergiant. A fraction of the stellar wind of the companion star is captured by the compact star, and produces X-rays as it falls onto the compact object.
In HMXB, the massive star dominates the emission of optical light. The compact object is the dominant source of X-rays. The massive stars are very luminous and therefore easily detected. One of the most famous HMXB is Cygnus X-1 which was the first stellar-mass black hole discovered. Soft-gamma rays emitters.
x##ray##xray##binary##binaries##high##mass##hmxb#hmxrb
HMXB
High-mass X-ray Binary
HXB
wcn stars
WR*
wc stars
WolfRayetStars
wolf##rayet##wolfrayet##star##wr
WR*
wr stars
Stars, Wolf-Rayet
wn stars
WOLF RAYET STARS
Stars:WR
WR
Wolf-Rayet Star
INTERACTING GALAXIES
IG
IG
galaxy in strong interaction with others (within a pair or a group)
interacting##galaxy##galaxies
InteractingGalaxies
Interacting Galaxy
Core Dominated
core##dominated##coredominated
Core/Extented Flux Ratio >1
BrownDwarfStars
1
Brown Dwarf
BROWN DWARF STARS
brown##dwarf##dwarves
Pulsar
pulsar##psr##pulsars
Pulsars
Psr
Pulsars
PSR
Pulsar
Pulsar
Optically variable pulsars (CM Tau), which are rapidly rotating neutron stars with strong magnetic fields, radiating in the radio, optical, and X-ray regions. Pulsars emit narrow beams of radiation, and periods of their light changes coincide with rotational periods (from 0.004 to 4 s), while amplitudes of the light pulses reach 0.8 mag.
PULSARS
Pulsars
Psr
S
SuperClG
Super Cluster of Galaxies
SUPERCLUSTERS
SCG
Superclusters
super##cluster##supercluster##galaxies##galaxy##superclusters##clusters##g##gal
AGN
ActiveGalacticNuclei
AGN
AGN
Active gal. nuclei
eruptive galaxies
ACTIVE GALAXIES
agn
ACTIVE GALACTIC NUCLEI
Active Galaxy Nucleus
AGN
ActiveGalaxies
agn##active##galaxy##nucleus##nuclei##galactic
AGN
Type1 QSO Active Galactic Nucleus
QSO type 1
qso##quasi##stellar##object##quasar##type1##type##1##quasars##objects##quasistellar##qsos
Star of Luminosity Class II
brilliant##giant##giants
Brilliant Giant
Type2 Seyfert Active Galactic Nucleus
Seyfert 2 Galaxy
Seyfert_2
seyfert2##2low##power##radio##quiet##agn##active##galaxy##nucleus##seyfert##galactic##nuclei##seyferts
Sy2
Variables of the RV Tauri type. These are radially pulsating supergiants having spectral types F-G at maximum light and K-M at minimum. The light curves are characterized by the presence of double waves with alternating primary and secondary minima that can vary in depth so that primary minima may become secondary and vice versa. The complete light amplitude may reach 3-4 mag in V. Periods between two adjacent primary minima (usually called formal periods) lie in the range 30-150 days.
Two subtypes are recognized:
- RV Tauri variables that do not vary in mean magnitude (AC Her);
- RV Tauri variables that periodically (with periods from 600 to 1500 days and amplitudes up to 2 mag in V) vary in mean magnitude (DF Cyg, RV Tau).
RV*
rv##tau##tauri##rvtau##rvtauri##star##variable##stars##variables
PulsV*RVTau
RV TAURI STARS
Variable Star of RV Tau type
RV
RvTauriStars
RV Tauri Variable Star
Radio-quiet AGN
radio##quiet##agn##active##galactic##nucleus##nuclei##galaxy
GiantBranchStars
GIANT BRANCH STARS
Giant
giant##giants
GiantStars
cs stars
Stars, giant
GIANT STARS
Star of Luminosity Class III
Supernova type I
SNI
supernova##supernovae##super##nova##novae##sn##typei##type1##type##1##i
Magnetar
magnetar##pulsar##magnetic##field##pulsars##magnetars
Stellar Black Hole
stellar##black##hole##blackhole##blackholes##holes
BlackHoles
BLACK HOLES
part##of##cloud##parts##clouds
PartofCloud
Part Of Cloud
PoC
PN
Planetary Nebula
Planetary_Nebulae
PN
A planetary nebula is a nebula surrounding a stellar remnant (white dwarf)
Planetary nebulae
PLANETARY NEBULAE
PN
PlanetaryNebulae
planetary##nebula##nebulae
M
supernova##explosion##processes##process
Supernova Explosion
Elliptical Galaxy
Ep GALAXIES
ELLIPTICAL GALAXIES
cD GALAXIES
E galaxies
EarlyTypeGalaxies
EARLY TYPE GALAXIES
EpGalaxies
cDGalaxies
EllipticalGalaxies
elliptical##galaxy##gal##galaxies##g
Variable stars with nonuniform surface brightness and/or ellipsoidal shapes, whose variability is caused by axial rotation with respect to the observer. The nonuniformity of surface brightness distributions may be caused by the presence of spots or by some thermal or chemical inhomogeneity of the atmosphere caused by a magnetic field whose axis is not coincident with the rotation axis.
Ro*
rotational##rotationally##variable##object##star##stars##objects##variables
RotatingStars
Rotationally Variable Object
RotV*
ROTATING STARS
LuminosityClassification
LuminosityClass
LUMINOSITY CLASSIFICATION
Luminosity Class
LUMINOSITY CLASS
luminosity##class
HV*
HighVelocityStars
High-velocity Star
highvelocity##high##velocity##star
HV*
HIGH VELOCITY STARS
Stars, high-velocity
Radio-loud AGN
agn##radio##loud##active##galactic##nucleus##nuclei##galaxy
non##stellar##body##bodies##object##objects##nonstellar
Non-stellar Body
Planets+Asteroids
Nonstellar
Nonstellar objects
Flat-Spectrum Radio Quasar, which is a Type1 active galactic nucleus
type##1##type1##flat##spectrum##radio##quasar##qso
Flat-Spectrum Radio Quasar
F STARS
FStars
f##fstar##star##stars##fstars
F Star
Stars, F-type
Star of Spectral Type F
RADIO GALAXY
rG
RadioGalaxies
RadioG
Radio Galaxy
radio##gal##galaxy##galaxies##g
Galaxies, radio
VELOCITY DISPERSION
VelocityDispersion
Velocity dispersion
eclipse##algol##process##processes
Eclipse of Algol Type
supernova##supernovae##super##nova##novae##sn##typeiib##type2b##type##2##ii##b##typeii##type2
Supernova type IIb
Temperature
temperature
TEMPERATURE
Nebulae
Nebula
Nebula
BrightNebulae
GASEOUS NEBULAE
FilamentsNebulae
Nebula
BRIGHT NEBULAE
COMPACT NEBULAE
GaseousNebulae
neb##nebula##nebulae
Neb
DiffuseNebulae
CompactNebulae
DIFFUSE NEBULAE
Nebulae
NEBULAE
FILAMENTS [NEBULAE]
FILAMENTARY NEBULAE
FilamentaryNebulae
L
The shockwave-generating process or the resulting Shockwave
Shockwave
SHOCK WAVES
ShockWaves
IONIZING SHOCK WAVES
shockwave##shock##wave##waves##shockwaves
IonizingShockWaves
thermal##continuum
Thermal Continuum
Black Body thermal continuum
YSO
YSO
Y*O
YSOs
YOUNG STARS
YSOs
YoungStars
yso##young##stellar##object##objects
Young Stellar Object (YSO)
1. Physical, an object in any of the Stages defined above. (Strom et al. 1975, ARAA, 13, 187)
2. Observational, an object in any of the Classes but with an infrared excess detectable in Spitzer surveys (a definition used by the c2d team to distinguish YSOs from the larger class of pre-mainsequence objects (PMS)
near IR emission, age around 10^6years
TT*
T Tauri Star
t##tauri##star##tau##ttauri##stars
T TAURI STARS
yy orionis stars
TTauriStars
INT,IT
O
spiral##arm##arms
arms
Spiral Arm
SpiralArms
SPIRAL ARMS
Spiral Arm of a galaxy
EUV
Extreme UV sources
EUV sources
extreme ultraviolet
euv
Proper_Motions
PROPER MOTIONS
pm##proper##motion
Proper motions
component of SpaceVelocity
ProperMotions
Proper Motion
Millimetric Radio Source
millimetric##radio##source
Radio(mm)
Millimetric/submm sources
mm
Galaxy in Pair
GiP
in##pair##galaxy##gal##galaxies##g
GinPair
DWARF GALAXIES
DwarfGalaxies
pr*
Pre-Main-Sequence Object (PMS) (NJE)
1. Observational, a star that lies above the main sequence.
Pre-Main Sequence Star
early stage stars
Stars, pre-main sequence
PremainsequenceStars
pre##main##sequence##star##stars
PREMAINSEQUENCE STARS
pMS*
PN
PN
planetary##nebula##shell##shells##nebulae
Planetary Nebula Shell
MINOR PLANETS
Asteroids
Minor planets
planetoids
asteroid##asteroids
MinorPlanets
ASTEROIDS
Asteroids
Asteroid
Protostars
Protostar
protostar##proto##star##protostars##stars
protostar (NJE)
1. Physical, an object that is still accreting mass and that will become or already is a main sequence star.
2. Physical, an object deriving most of its luminosity from accretion and that will become a main sequence star.
3. Physical, the entire structure of central star, disk, and envelope.
Comments: The first definition allows the inclusion of massive protostars, which can be already burning nuclear fuel but still growing in mass. The second does not allow them above a certain mass where the nuclear-burning luminosity exceeds that from accretion. Both the first two apply to the central object, while the third refers to the entire structure. For the first two definitions, objects in Stages 0, I, or II could host protostars; For the third definition, only Stages 0 and I would be protostars.
PROTOSTARS
Protostars
CH*
CH*
ch##envelope##type##star
CH Envelope-type Star
twenty one cm line
21 CM LINE
21CmLine
h##hydrogen##line##emission##process##processes
far##ir##infrared##source
IR>30ยต
Far-IR Source
FIR
BSubdwarfStars
B SUBDWARF STARS
herbig stars
Emission-line Star
AeStars
Em*
Em*
emission##line##emissionline##star
Ae STARS
Stars:Emission
H II regions
HII (inonized) region
H II REGIONS
HII Region
HII
HII
CompactHIiRegions
HII_regions
COMPACT H II REGIONS
HIiRegions
hii##region##regions
HII
NEUTRON STARS
neutron##star##stars
Neutron Star
NeutronStars
BetaCepheiStars
beta canis majoris stars
ultra short period variable stars
Beta Cephei Variable
53PerseiStars
cephei##cep##beta##cepheid##cma##variables##variable
BCEP
ultra short period B stars
PulsV*bCep
53 PERSEI STARS
BETA CEPHEI STARS
Variables of the Beta Cephei type (Beta Cep, Beta CMa), which are pulsating O8-B6 I-V stars with periods of light and radial-velocity variations in the range of 0.1 - 0.6 days and light amplitudes from 0.01 to 0.3 mag in V. The light curves are similar in shape to average radial-velocity curves but lag in phase by a quarter of the period, so that maximum brightness corresponds to maximum contraction, i.e., to minimum stellar radius. The majority of these stars probably show radial pulsations, but some (V649 Per) display nonradial pulsations; multiperiodicity is characteristic of many of these stars.
Sub-type:
- A short-period group of Beta Cep variables. The spectral types are B2-B3 IV-V; periods and light amplitudes are in the ranges 0.02 - 0.04 days and 0.015 - 0.025 days, respectively, i.e., an order of magnitude smaller than the normally observed ones.
bC*
Variable of the Beta Cep type
galactic##galaxy##morphology##elliptical
E
galactic##galaxy##morphology##dwarf##elliptical
dE
Parallaxes
Parallaxes
PARALLAXES
Parallaxes, trigonometric
Thermonuclear Supernova Explosion
supernova##explosion##thermonuclear##thermo##nuclear##process##processes
CircumstellarShells
shell##shells
CIRCUMSTELLAR SHELLS
Shell
SUBGIANT STARS
Star of Luminosity Class IV
SubgiantStars
Subgiant
sub##giant##subgiant##giants##subgiants
Clusters of Galaxies
ClG
Cluster of Galaxies
GClstr
ClG
Clusters_of_galaxies
cluster##galaxy##galaxies##clusters##g##gal
ClustersOfGalaxies
CLUSTERS OF GALAXIES
clusters of galaxies
Cluster of Galaxies
Clusters, galaxy
galaxy clustering
galaxy clusters
Steep-spectrum Radio Quasar
steep##spectrum##radio##quasar##qso##quasi##stellar##object##objects
NEAR INFRARED RADIATION
Near Infrared
Wavelength under 10 microns
near##ir##infrared
NearInfraredRadiation
MICROLENSING
Microlensing
Micro-lensing
microlensing##micro##lensing##process##processes
portion##of##stellar##object##objects##portions
Portion of Stellar Object
any component of a stellar object
Galaxy with High Redshift
HzG
high##redshift##galaxy##gal##galaxies##g
High_z_G
SStars
S*
se stars
s##type##stype##star##sstar##stars##sstars
S*
S-type Star
S STARS
l##ltype##type##irregular##stars##star
L-type Irregular Star
star##burst##starburst
Starburst Process
OpCl
Clusters, open
OpenStarClusters
OPEN STAR CLUSTERS
galactic clusters
Open_clusters
OpC
open##cluster##star##stars##clusters
Open Cluster
Starburst Galaxy
StarburstGalaxies
starburst##gal##galaxy##galaxies##g
SBG
StarburstG
STARBURST GALAXIES
B Star
Bw STARS
BStars
bstar##b##star##stars##bstars
BwStars
B STARS
Stars, B-type
Star of Spectral Type B
ASupergiantStars
A SUPERGIANT STARS
Weak-line T Tauri
Weak-line T Tauri Star (WTTS)
1. (Original) Observational, a โsolar-typeโ (Mโ ~0.5Mโ, K7-M0), age ~1 Myr, pre-main sequence star (from HRD location) that has W(Hฮฑ) < 10ร
.
Description: The limit was chosen in order to separate objects which showed the signatures of optically thick accretion disks (based on IRAS + NIR SEDs) from those that appeared to be photospheric.
2. (More modern) Observational, any pre-main sequence star that shows no evidence of accretion based on an age and spectral-type appropriate W(Halpha).
Description: Firm inclusion in the class would require additional information from high resolution, high S/N spectra to test for the presence (CTTS) or absence (WTTS) of Hฮฑ profiles indicative of accretion, or signatures (e.g., forbidden [OI] or [SII]) of winds driven by accretion.
3. Physical, a young star that is no longer surrounded by an accretion disk.
Comments: The definition of WTTS was introduced to link signatures of accretion (Halpha emission; forbidden line emission) diagnosed from the presence/kinematics of gas, with signatures of optically thick disks provided by IR SEDs. The definition that was applied to the initial Taurus sample is obsolete, in the sense that the W(Halpha) = 10ร
limit is an appropriate (and only approximate) discriminant for Taurus-age stars with masses ~ 0.5 Mโ. However, the idea of using both gas and dust diagnostics to assess the physical state of the disk is still enormously valuable. In particular, it is by using both SEDs and gas diagnostics that we can probe the evolutionary state of transition/anemic disks and assess/constrain the likely physical cause for the observed SED signature.
wtts##weak##line##t##tau##tauri##star##stars##ttauri##weakline
radio##cm##centimetric
Radio Centimetric
Atomic Element
atomic##element
ATOMS
Atoms
Cepheid variable star
DOUBLE MODE CEPHEIDS
CEPHEIDS
Ce*
bump cepheids
DoubleModeCepheids
Cepheid
Cepheid
CEP
cepheid variable stars
DwarfCepheids
DWARF CEPHEIDS
Cepheids. Radially pulsating, high luminosity (classes Ib-II) variables with periods in the range of 1-135 days and amplitudes from several hundredths to 2 mag in V (in the B band, the amplitudes are greater). Spectral type at maximum light is F; at minimum, the types are G-K. The longer the period of light variation, the later is the spectral type. The maximum of the surface-layer expansion velocity almost coinciding with maximum light.
Sub-type:
- Cepheids (TU Cas, V 367 Sct) displaying the presence of two or more simultaneously operating pulsation modes (usually the fundamental tone with the period P0 and the first overtone P1). The periods P0 are in the range from 2 to 7 days, with the ratio P1/P0 approx. 0.71.
Cepheids
cepheid##cep##cephei##cepeids##variables##variable
I
galactic##galaxy##morphology##irregular
Compact_Gr_G
CGG
Compact Group of Galaxies
compact##galaxy##galaxies##group##groups
Rotation-powered Pulsar
rotation##powered##pulsar##psr##pulsars
Gamma Doradus Variable
gD*
gamma##doradus##variable##variables##stars##star
Variable Star of gamma Dor type
Gamma Doradus variables are variable stars which display variations in luminosity due to non-radial pulsations of their surface. The stars are typically young, early F or late A type main sequence stars, and typical brightness fluctuations are 0.1 magnitudes with periods on the order of one day. This is a relatively new class of variable stars, having been first characterised in the second half of the 1990s, and details on the underlying physical cause of the variations remains under investigation.
gammaDor
PM*
high##proper##motion##star
High-proper motion Star
PM*
III
eclipsing variable stars
E
ECLIPSING BINARY STARS
Binaries:eclipsing
eclipsing##binary##star##stars##binaries
Binary systems with orbital planes so close to the observer's line of sight (the inclination i of the orbital plane to the plane orthogonal to the line of sight is close to 90 deg) that the components periodically eclipse each other. Consequently, the observer finds changes of the apparent combined brightness of the system with the period coincident with that of the components' orbital motion.
Binaries, eclipsing
EclipsingBinaryStars
EB*
EB*
photometric binary stars
eclipsing stars
Eclipsing Binary
Post-AGB Star
post-AGB*
postagb##post##agb##asymptotic##giant##branch##star
pA*
Old Disk
Galactic Sperical Component (old disk)
old##disk##galactic##sperical##component##disks##components
X RAYS
X-Rays
XRays
X-Ray
X ray radiation
x##ray##xray##rays##xrays
Spectra, infrared
Infrared
INFRARED
IR
ir##infrared
Infrared
FUOr*
Variable Star of FU Ori type
FU
FuOrionisStars
fu##orionis##orion##variable##star##stars##variables
FU ORIONIS STARS
FU*
Orion variables (eruptive) of the FU Orionis type. Characterized by gradual increases in brightness by about 6 mag in several months, followed by either almost complete constancy at maximum that is sustained for long periods of time or slow decline by 1-2 mag. Spectral types at maximum are in the range Ae(alpha) - Gpe(alpha). After an outburst, a gradual development of an emission spectrum is observed and the spectral type becomes later. These variables probably mark one of the evolutionary stages of T Tauri-type Orion variables, as evidenced by an outburst of one member, V1057 Cyg, but its decline (2.5 mag in 11 years) commenced immediately after maximum brightness was attained. All presently known FU Ori variables are coupled with reflecting cometary nebulae.
FU Orionis Variable Star
GIANT ELLIPTICAL GALAXIES
giant##elliptical##galaxy##gal##galaxies##g
Giant Elliptical Galaxy
GiantEllipticalGalaxies
RfNeb
RNe
Reflection Nebula
REFLECTION NEBULAE
reflection##nebula##nebulae
RfN
ReflectionNebulae
dwarf##irregular##galaxy##gal##galaxies##g
Dwarf Irregular Galaxy
K
GiantGalaxies
GIANT GALAXIES
Variables of the Delta Scuti type. These are pulsating variables of spectral types A0-F5 III-V displaying light amplitudes from 0.003 to 0.9 mag in V (usually several hundredths of a magnitude) and periods from 0.01 to 0.2 days. The shapes of the light curves, periods, and amplitudes usually vary greatly. Radial as well as nonradial pulsations are observed. The variability of some members of this type appears sporadically and sometimes completely ceases, this being a consequence of strong amplitude modulation with the lower value of the amplitude not exceeding 0.001 mag in some cases. The maximum of the surface layer expansion does not lag behind the maximum light for more than 0.1 periods. Delta Sct stars are representatives of the galactic disk (flat component) and are phenomenologically close to the SX Phe variables.
Sub-type:
- Low amplitude group of Delta Sct variables (light amplitude <0.1 mag in V). The majority of this type's representatives are stars of luminosity class V; objects of this subtype generally are representative of the Delta Sct variables in open clusters.
DELTA DELPHINI STARS
DeltaScutiStars
DELTA SCUTI STARS
dS*
DSCT
DeltaDelphiniStars
delta##scuti##deltascuti##variable##variables##stars##star
Delta Scuti Variable Star
Variable Star of delta sct type
PulsV*delsct
dwarf##elliptic##galaxy##gal##galaxies##g
Dwarf Elliptical Galaxy
association##star##stars##associations
*Ass
AS*
Assoc*
STAR ASSOCIATIONS
Associations, stellar
Associations
StarAssociations
Association of Stars
Period
period
Period
PERIOD
white dwarf with He II lines
disc##discs##disk##disks##circumstellar
circumstellar disk (LH)
1. Physical, any disk of gas and/or dust surrounding a star.
2. Physical, a disk surrounding only a single star, not a binary.
CircumstellarDisks
Circumstellar disk
CIRCUMSTELLAR DISKS
galactic##galaxy##morphology##peculiar
symbiotic novas
Symbiotic Star
SYMBIOTIC STARS
symbiotic##star##stars
SymbioticStars
Symbiotic variables of the Z Andromedae type. They are close binaries consisting of a hot star, a star of late type, and an extended envelope excited by the hot star's radiation. The combined brightness displays irregular variations with amplitudes up to 4 mag in V. A very inhomogeneous group of objects.
Symbiotic*
ZAND
Sy*
DoubleModeVariableStars
Variable Star
VARIABLE STARS
Stars:variable
DOUBLE MODE VARIABLE STARS
V*
V*
Variable stars
V*
VariableStars
variable##star##stellar##object##objects##variability##stars
Stars, variable
Binaries:spectroscopic
binary##binaries##spectroscopic##doubles##double##sb##sbs
SB*
spectrum binary stars
DeltaDelphiniStars
Spectroscopic Binary
SpectroscopicBinaryStars
SB
Binaries, spectroscopic
DELTA DELPHINI STARS
SPECTROSCOPIC BINARY STARS
cosmological##lensing##lens##process#processes
Cosmological Lensing
bllac##bl##Lac##object##lacertae##objects##bllacertae#lacertae
BLL
bl lac objects
BLLac
BL Lac objects
BLLac
BL Lacertae Object, Type1 Active Galactic Nucleus
BL LACERTAE OBJECTS
BL_Lac_objects
BLLAC
BlLacertaeObjects
radial##pulsation##pulse##pulsating##process##processes
Radial Pulsation
dI
galactic##galaxy##morphology##dwarf##irregular
spectral##index
Spectral Index
high##mass##star##highmass##stars
High-mass Star
omicron ceti stars
mira##ceti##omicron##variable##variables##stars##star##miraceti
M
Mi*
Variable Star of Mira Cet type
miras
Mira
zeta aurigae stars
Mira (Omicron) Ceti-type variables. These are long-period variable giants with characteristic late-type emission spectra (Me, Ce, Se) and light amplitudes from 2.5 to 11 mag in V. Their periodicity is well pronounced, and the periods lie in the range between 80 and 1000 days. Infrared amplitudes are usually less than in the visible and may be <2.5 mag. For example, in the K band they usually do not exceed 0.9 mag.
Mira Ceti Variable
MIRA VARIABLE STARS
MiraVariableStars
carbon##star##c##cstar##stars##cstars##carbonstars
CarbonStars
c stars
C*
CARBON STARS
Carbon Star
C*
C*
Non-periodic process
non##not##periodic##process##processes
alternate name: proplyd
Protoplanetary disk
protoplanetary disk (CL)
1. Physical, a primordial disk with the potential to form planets.
protoplanetary##proto##planetary##disk##proplyd##proplyds##disks
blu
Blue Object
Blue
Blue*
BLUE OBJECTS
blue##object
Blue_objects
Blue objects
BlueObjects
Any component of a galaxy
Portion of Galaxy
portion##of##galaxy##galaxies##portions
N
prenovas
Close binary systems with orbital periods from 0.05 to 230 days. One of the components of these systems is a hot dwarf star that suddenly, during a time interval from one to several dozen or several hundred days, increases its brightness by 7-19 mag in V, then returns gradually to its former brightness over several months, years, or decades. Small changes at minimum light may be present. Cool components may be giants, subgiants, or dwarfs of K-M type. The spectra of novae near maximum light resemble A-F absorption spectra of luminous stars at first. Then broad emission lines (bands) of hydrogen, helium, and other elements with absorption components indicating the presence of a rapidly expanding envelope appear in the spectrum. As the light decreases, the composite spectrum begins to show forbidden lines characteristic of the spectra of gas nebulae excited by hot stars. At minimum light, the spectra of novae are generally continuous or resemble the spectra of Wolf-Rayet stars. Only spectra of the most massive systems show traces of cool components.
Some novae reveal pulsations of hot components with periods of approximately 100 s and amplitudes of about 0.05 mag in V after an outburst. Some novae eventually turn out to be eclipsing systems. According to the features of their light variations, novae are subdivided into fast, slow, very slow, and recurrent categories.
NOVAS
No*
Nova
Novae
Novae
Nova
symbiotic novas
Novas
nova##novae
Nova
Disk
disc##discs##disk##disks
em##electromagnetic##specrum##range
EM Spectrum Range
ELECTROMAGNETIC WAVES
ElectromagneticWaves
RADIATION
electromagnetic radiation
Set of ranges in the electromagnetic spectrum
Radiation
DQHerCataclysmicVariable
DQ Herculis
DQHer
Cataclysmic Variable Star DQ Her type
dq##herculis##cataclysmic##variable##star##stars##dqherculis##variables
DQ HERCULIS STARS
DQ*
G SUBDWARF STARS
GSubdwarfStars
FSubgiantStars
R Coronae Borealis Variable
RCB
Variable Star of R CrB type
RCoronaeBorealisStars
rcb##r##coronae##borealis##variable##variables##stars##star##variable##variables
RC*
Variables of the R Coronae Borealis type. These are hydrogen-poor, carbon- and helium-rich, high-luminosity stars belonging to the spectral types Bpe-R, which are simultaneously eruptive and pulsating variables. They show slow nonperiodic fadings by 1-9 mag in V lasting from a month or more to several hundred days. These changes are superposed on cyclic pulsations with amplitudes up to several tenths of a magnitude and periods in the range 30-100 days.
rcb stars
R CORONAE BOREALIS STARS
Erupt*RCrB
Mass
Masses
MASS
mass
Mass
CocoonStars
OH/IR
COCOON STARS
OH/IR Envelope-type Star
OH*
OhIrStars
OH IR STARS
oh##ir##envelope##star##stars##ohir
Stars, G-type
GStars
G Star
g##gstar##star##gstars##stars
Star of Spectral Type G
G STARS
Unknown
?
Object of unknown nature
unknown
supernova##supernovae##super##nova##novae##sn##supernovae##super##nova##novae##sn##typeii##type2##type##2##ii
Supernova type II
SNII
Part of Galaxy
PoG
part##of##galaxy##parts##galaxies
PartofG
PofG
Emission Process
emission##process##processes
EMISSION PROCESSES
EmissionProcesses
Ages
Age
AGE
Stars, ages
Non-radial Pulsation
not##non##radial##pulsation##pulse##pulsating##process##processes
F SUPERGIANT STARS
FSupergiantStars
GroupG
group##galaxies##galaxy##groups
GROUPS OF GALAXIES
Group of Galaxies
GroupsOfGalaxies
GrG
GGroup
F
white dwarf with He I lines
Classical T Tauri Star (CTTS)
1. (Original) Observational, a solar-type PMS star that exhibits at least one of the following:
(a) broad, strong Halpha emission (Joy, 1945, ApJ 102, 168);
(b) ultraviolet excess emission (above photospheric levels);
(c) forbidden and in some cases permitted line emission; and (d) irregular optical variability.
Description: Such stars can exhibit IR SEDs that span Class I-II, and in some cases, Transition Disk SEDs (see below). Typical examples are AA Tau; BP Tau (Class II); and HL Tau, DG Tau. 2. Physical, A solar-type PMS star surrounded by an accretion disk, and in some cases, an accretion disk and a โremnantโ envelope. An accretiondriven wind, manifest in emission line spectra, is also present.
Description: The key distinguishing characteristics are the presence of an accretion disk and an accretion-driven wind. However, CTTS cover a โbroadโ range of evolutionary stages.
Classical T Tauri
ctts##classical##t##tauri##star##tau##stars##ttauri
CENTRAL STARS
Planetary Nebula Central Star
planetary##nebula##central##star##stars
CentralStars
Photosphere
Photosphere
photosphere
PHOTOSPHERE
EXTENDED SOURCES
EXTENDED OBJECTS
ExtendedSources
Extended
extended##morphology
ExtendedObjects
Radio Source
Radio
ExtragalacticRadioSources
RadioSources
radio##source
radio
RadioS
RADIO SOURCES
Rad
Radio
EXTRAGALACTIC RADIO SOURCES
Radio sources
CompactGalaxies
Compact Morphology
CompactObjects
COMPACT NEBULAE
CompactSources
COMPACT SOURCES
COMPACT OBJECTS
compact##morphology
CompactNebulae
CompactHIiRegions
CompactNuclei
COMPACT NUCLEI
COMPACT H II REGIONS
COMPACT GALAXIES
K Star
Star of Spectral Type K
Stars, K-type
kstar##k##star#stars##kstars
Alpha2CanumVenaticorumStars
Variable Star of alpha2 CVn type
Alpha2 Canum Venaticorum Variable
alpha##2##alpha2##cv##cvn##canum##venaticorum
ACV
Alpha2 Canum Venaticorum variables. These are main-sequence stars with spectral types B8p-A7p and displaying strong magnetic fields. Spectra show abnormally strong lines of Si, Sr, Cr, and rare earths whose intensities vary with rotation. They exhibit magnetic field and brightness changes (periods of 0.5-160 days or more). The amplitudes of the brightness changes are usually withine 0.01-0.1 mag in V.
Sub-type:
- Rapidly oscillating Alpha2 CVn variables. These are nonradially pulsating, rotating magnetic variables of Ap spectral type (DO Eri). Pulsation periods are in the range of 6-12 mmag (0.004-0.01 days), while amplitudes of light variation caused by the pulsation are about 0.01 mag in V. The pulsational variations are superposed on those caused by rotation.
RotV*alf2CVn
ALPHA 2 CANUM VENATICORUM STARS
a2*
BY
Varaible Star of BY Dra type
BYDra
BY Draconis Variable
by##draconis##variable##star##stars##variables
ByDraconisStars
BY*
BY Draconis-type variables, which are emission-line dwarfs of dKe-dMe spectral type showing quasiperiodic light changes with periods from a fraction of a day to 120 days and amplitudes from several hundredths to 0.5 mag in V. The light variability is caused by axial rotation of a star with a variable degree of nonuniformity of the surface brightness (spots) and chromospheric activity.
Some of these stars also show flares similar to those of UV Cet stars, and in those cases they also belong to the latter type and are simultaneously considered eruptive variables.
BY DRACONIS STARS
IrS
IR
ir##infrared##source
Infrared Source
Infrared:stars
INFRARED SOURCES
InfraredSources
IR
Infrared sources
Infrared
Pulsations
DoubleModePulsation
DOUBLE MODE PULSATION
PULSATIONS
pulsation##process##processes##pulse##pulsating
Pulsation Process
Stars, distances
I
FANAROFF RILEY CLASS
Fanaroff-Riley Type-1 Object
fanaroff##riley##type##1##type1##agn##active##galatic##nucleus##nuclei##galaxy
Fanaroff-Riley Type I, which is a Type2 Active Galactic Nucleus
FanaroffRileyClass
blue
Blue
blazar##blazars
Blazars
BLAZARS
Blazar
Bla
Blazar
Debris disk
debris##disk##disc##disks##discs
debris disk (LH)
1. Physical, circumstellar disk composed of rock, dust, and ice.
2. Physical, gas-poor circumstellar disk in which the primary physical process is the collisional grinding down of planetesimals into smaller particles, eventually dust which is known as โsecond generationโ dust.
3. Physical, optically thin disk in which material is removed from the system via various drag or blowout scenarios on timescales much less than the age of the star.
Description: Indicator of a planetary system given that large, planetary-mass bodies are required in order to induce and maintain the collisional cascade. In our Solar System, the Asteroid Belt and the Kuiper Belt are well-separated debris belts that would be considered a tenuous debris disk if viewed from afar.
Star of Luminosity Class V
DwarfStars
Stars, dwarfs
DWARF STARS
dwarves##dwarf
Dwarf
G
Process
process
Phenomenon or associated process
process##processes
DegenerateStars
1
Stellar Remnant
DegenerateDwarfStars
stellar##remnant##remnants
DEGENERATE STARS
DEGENERATE DWARF STARS
white dwarf with hydrogen lines
Redshift
Redshifts
Redshifts
-12 < value < 12
REDSHIFT
redshift##red##shift
Redshift
HI
hi##region##cold##regions
Cold HI Region
HI
Spectral types
Any class in Morgan Keeman's spectral classification
SPECTRAL TYPES
SpectralTypes
spectral##type
MK spectral classification
Spectral Type
Spectral_Classification
RR*
RR
RR LYRAE STARS
ab variable stars
rr##lyrae##variable##star##stars##variables##rrlyrae
RrLyraeStars
cluster type variable stars
Variable Star of RR Lyr type
RRLyr
RR Lyrae Variable
Variables of the RR Lyrae type, which are radially-pulsating giant A-F stars having amplitudes from 0.2 to 2 mag in V. Cases of variable light-curve shapes as well as variable periods are known. If these changes are periodic, they are called the "Blazhko effect."
Traditionally, RR Lyrae stars are sometimes called short-period Cepheids or cluster-type variables. The majority of these stars belong to the spherical component of the Galaxy; they are present, sometimes in large numbers, in some globular clusters, where they are known as pulsating horizontal-branch stars. Like Cepheids, maximum expansion velocities of surface layers for these stars practically coincide with maximum light.
Sub-types:
- RR Lyrae variables showing two simultaneously operating pulsation modes, the fundamental tone with the period P0 and the first overtone, P1 (AQ Leo). The ratio P1/P0 is approximately 0.745;
- RR Lyrae variables with asymmetric light curves (steep ascending branches), periods from 0.3 to 1.2 days, and amplitudes from 0.5 to 2 mag in V;
- RR Lyrae variables with nearly symmetric, sometimes sinusoidal, light curves, periods from 0.2 to 0.5 days, and amplitudes not greater than 0.8 mag in V (SX UMa).
LSB_G
LSB
low##surface##brightness##lsb##gal##galaxy##galaxies##g
Low Surface Brightness Galaxy
Synchrotron Emission
synchrotron##emission##process##processes
emission synchrotron
G_Lens
Lensed Galaxy
LeG
lensed##gravitationnal##gal##galaxy##galaxies##g
Gravitationnaly Lensed Image of a Galaxy
LensedG
polarization
light polarization
POLARIZATION [WAVES]
PolarizationWaves
ContactBinaryStars
Contact
CONTACT BINARY STARS
contact
nebular##continuum
Recombination thermal continuum
Nebular Continuum
red##super##giant##supergiant##giants##supergiants
Red Supergiant
pulsating##alpha##2##alpha2##cv##cvn##canum##venaticorum
Pulsating Alpha2 Canum Venaticorum
association of stars of type O or B
association##star##stars##associations##ob##o##b
OB ASSOCIATIONS
ObAssociations
high##velocity##cloud##coulds##hvc##hvcld
HIGH VELOCITY CLOUDS
HVCld
HVC (High Velocity Cloud)
High-velocity Cloud
HVC
HighVelocityClouds
Class
class##type
Continuum Non-thermal
continuum##non##not##thermal
SeyfertGalaxies
SEYFERT NUCLEI
SEYFERT GALAXIES
low##power##radio##quiet##agn##active##galaxy##nucleus##seyfert##galactic##nuclei##seyferts
Seyfert_Galaxies
SeyfertNuclei
Seyfert
SyG
Seyfert Galaxy
Galaxies, Seyfert
An individual star located in a star cluster
stellar##object##star##in##cluster
*iC
Stellar Object in Cluster
*inCl
Measured observational parameters/properties
Measurement
Measurement
measure##measurement##measures##measurements
MEASUREMENT
accretion##powerred##pulsar##psr##pulsars##
Accretion-powered Pulsar
Flux Amplitude Variation
flux##amplitude##variation
Core Collapse Supernova Explosion
supernova##explosion##core##collapse##process##processes
Polar Ring Galaxy
polar##ring##gal##galaxy##galaxies##g
A
Chromosphere
chromosphere
CHROMOSPHERE
Chromosphere
Sy1
seyfert##seyfert1##1##low##power##radio##quiet##agn##active##galaxy##nucleus##galactic##nuclei##seyferts
Type1 Seyfert Active Galactic Nucleus
Seyfert 1 Galaxy
Seyfert_1
asymptotic##giant##branch##star##agb##stars
AGB Star
AG*
Asymptotic Giant Branch Star
AGB*
Flux Ratio
flux##ratio
G SUBGIANT STARS
GSubgiantStars
G Subgiant Star
PECULIAR GALAXIES
Peculiar Galaxy
Galaxies, peculiar
peculiar##gal##galaxy##galaxies##g
PeculiarGalaxies
II
white dwarfs with continuous spectrum
ovv##optically##variable##objects##object
OVV
OVV
Optically Violently Variable Object
ECLIPSES
eclipse##eclipsing##process##processes
Eclipse
Eclipses
Abundances, [Fe/H]
Abundances
ABUNDANCE
Abundance
Abundances, peculiar
Abundances
Light Curve
light##curve
LIGHT CURVES
LightCurves
ptts##post#t##tauri##ttauri##star##stars##post-t
Post-T Tauri star (PTTS) (SES)
1. Observational, a young star that exhibits a photospheric spectrum over a wavelength range from the NIR and longward.
Description: Among solar-type PMS stars, such objects can be identified from their location in the HRD, from their x-ray properties supplemented by HRD location (confirmed from parallaxes; radial velocities; clear membership in a cluster.....) plus a robust SED. Among higher mass stars, such objectsmight be called โPost Ae/Be starsโ and can be identified via their location in the HRD in a cluster/association plus robust SEDs.
2. Physical, a young star of any mass that no longeris surrounded by a circumstellar accretion disk.
3. Physical, an evolutionary step between T Tauri Stars and ZAMS, generally thought to refer to stars on the radiative track.
Comments: In these definitions, there is no physical
difference between a WTTS and a post-TTS.
Itโs just the choice of observational โtoolโ for certifying
that such an object is no longer accreting
material. There is some sentiment on the committee
for specifying that a Post-T Tauri star is older
than either a CTTS or a WTTS (e.g., with ages of
5-30 Myr). See also naked T Tauri star.
Naked T Tauri star (NTTS) (supplied by Scott Wolk and Fred Walter)
1. Observational, a low mass pre-main sequence star that exhibits no evidence of an optically thick circumstellar disk or on-going accretion.
Description: In this picture, a NTTS differs from a post-T Tauri star in being an observational definition while the PTTS is described by definition 3 for post-T Tauri Star.
Post-T Tauri Star
Naked T Tauri stars are basically the same as Post-T Tauri stars.
g##gtype##super##giant##supergiant##supergiants##star##stars
GSupergiantStars
G SUPERGIANT STARS
G Supergiant Star
B
Spiral Galaxy
spiral##gal##galaxy##galaxies##g
SPIRAL GALAXIES
SpiralGalaxies
RS
rs##canum##venaticorum##cv##rscv##binary##binaries
RS*
Variable of RS CVn type
RSCVn
Eruptive variables of the RS Canum Venaticorum type. This type is ascribed to close binary systems with spectra showing Ca II H and K in emission, their components having enhanced chromospheric activity that causes quasi-periodic light variability. The period of variation is close to the orbital one, and the variability amplitude is usually as great as 0.2 mag in V (UX Ari). They are X-ray sources and rotating variables. RS CVn itself is also an eclipsing system.
RS Canum Venaticorum Variable Star
Subdwarf
Star of LuminosityClass VI
subdwarf##sub##subdwarves
Cl*
clusters of stars
Cl*
*Cl
STAR CLUSTERS
cluster##star##stars##clusters
Star Cluster
Cluster of Stars
StarClusters
LineWidths
line##width
LINE WIDTHS
Line Width
spectral line widths
lensed##quasar##qso##gravitationnaly##quasars##quasistellar##quasi##stellar##qsos
Lensed Quasar
Gravitationnaly Lensed Image of a Quasar
LeQ
LensedQ
Q_Lens
uv##ultraviolet##ultra##violet
ULTRAVIOLET
Ultraviolet
UV
ultraviolet light
uv
ULTRAVIOLET RADIATION
UltravioletRadiation
Ultraviolet
Ultraviolet
Spectra, ultraviolet
gamma##ray##source
gamma
gam
GAMMA RAY SOURCES
GammaRaySources
Gamma-ray Source
GammaS
PLANETS
GiantPlanets
Planets
ExtrasolarPlanets
GIANT PLANETS
EXTRASOLAR PLANETS
Planet?
planet##planets
Planets
(Extra-solar) Planet (or candidate)
Planet
Planets
Pl?
IrregularGalaxies
irregular##galaxy##gal##galaxies##g
IRREGULAR GALAXIES
Irregular Galaxy
RADIO WAVES
twenty one cm line
21 CM LINE
Radio
RadioWaves
radio
Radio
RadioFrequencies
21CmLine
RADIO EMISSION
RADIO FREQUENCIES
RadioEmission
dwarf##spiral##galaxy##gal##galaxies##g
Dwarf Spiral Galaxy
DOUBLE GALAXIES
pair##gal##galaxy##galaxies##pairs##g##gal##double
Galaxy Pair
2
PaG
PairG
DoubleGalaxies
GPair
XRayS
X
X RAY SOURCES
xray
x-ray
X
X-ray sources
X-ray Source
XRaySources
power##radio##mhz##powerradiomhz##radiomhz
Power Radio Mhz
B SUPERGIANT STARS
BSupergiantStars
Close
close##morphology
Diffuse clouds
CLOUDS
DENSE CLOUDS
DenseClouds
cloud##clouds##cld
Clouds
Lenticular Galaxy
EarlyTypeGalaxies
EARLY TYPE GALAXIES
lenticular##gal##galaxy##galaxies##g
Variability Time Scale
time##scale##timescale##variability
herbig stars
Herbig star
HerbigHaroObjects
Herbig Ae/Be Stars (NC)
1. Observational, a category of spectral type A and B stars that exhibit properties similar to those of CTTS: strong optical emission lines and infrared to millimeter excesses consistent with disk emission.
2. (Orig.) Observational, Herbig (1962) first drew attention to a set of early type objects with emission lines, associated with localized nebulosity and larger scale dark clouds. As is the case for CTTS/WTTS, the original classification implied nothing about the presence of disks, though disks were later recognized as the physical driver for many of the observational characteristics. Description: These systems are interpreted as pre-main sequence and zero-age main sequence objects, with ages comparable to CTTS and WTTS but larger masses, 2 < Mโ/Mโ < 10. They are often referred to as just โHerbig Starsโ.
HH
AeStars
hh objects
Ae STARS
HH
herbig##haro##herbigharo##object##ae##be##star##stars
HERBIG HARO OBJECTS
C
galactic##galaxy##morphology##dwarf
Power Radio Ghz
power##radio##ghz##radioghz##powerradioghz
U Geminorum-type variables, quite often called dwarf novae. They are close binary systems consisting of a dwarf or subgiant K-M star that fills the volume of its inner Roche lobe and a white dwarf surrounded by an accretion disk. Orbital periods are in the range 0.05-0.5 days. Usually only small, in some cases rapid, light fluctuations are observed, but from time to time the brightness of a system increases rapidly by several magnitudes and, after an interval of from several days to a month or more, returns to the original state. Intervals between two consecutive outbursts for a given star may vary greatly, but every star is characterized by a certain mean value of these intervals, i.e., a mean cycle that corresponds to the mean light amplitude. The longer the cycle, the greater the amplitude. These systems are frequently sources of X-ray emission. The spectrum of a system at minimum is continuous, with broad H and He emission lines. At maximum these lines almost disappear or become shallow absorption lines. Some of these systems are eclipsing, possibly indicating that the primary minimum is caused by the eclipse of a hot spot that originates in the accretion disk from the infall of a gaseous stream from the K-M star. According to the characteristics of the light changes, U Gem variables may be subdivided into three types: SS Cyg, SU UMa, and Z Cam.
Dwarf Nova
DN*
UG
Dwarf Nova (U Geminorum-type variable star)
dwarf##nova##novae##u##geminorum
DwarfNova
supernova##supernovae##super##nova##novae##sn##typeia##type1a##type##1a##ia##a##1##i
Supernova type Ia
FSubDwarfStars
F SUBDWARF STARS
qso##2##quasar##qso2##object##objects##quasi##stellar##quasistellar##type##2##type2##quasars##qsos
QSO2
Type2 QSO Active Galactic Nucleus
Large Separation Lobes
large##separation##lobes##radio
Accretion Disks
Accretion Disk
ACCRETION DISKS
accretion disk (SES)
1. Observational, signified via at least one of the following:
(a) broad Halpha emission, which at appropriate resolution and S/N exhibits kinematic signatures of accretion (inverse P-Cygni);
(b) ultraviolet excess emission (above photospheric levels),
(c) gas in Keplerian rotation around the star;
(d) 5 large amplitude and irregular photometric variability.
Description: the excess UV is thought to arise from hot spots from accreting matter. It is often combined with emission lines (e.g. CO, [NeII], HCN, ...) that exhibit the characteristic double-horned profiles indicative of gas that could supply the accretion.
2. Physical, a disk โ isolated or fed by material infalling from a protostellar envelope โ which is transporting material inward toward the stellar surface.
accretion##disk##disks##disc##discs
galactic##galaxy##morphology
Galaxy Morphology
HI
H I REGIONS
HICLOUDS
HI Region
HIClouds
H I data
HI
hi##region##regions
HIRegions
HI (neutral) region
red
Red
giant##giants##star##stars##A##A-type
AGiantStars
A GIANT STARS
LINER AGN
liner##agn##galactic##nucleus##nuclei##liners##galaxy
LINER-type Active Galaxy Nucleus
LIN
LINER
Eclipsing Binary of Algol type
EB*Algol
AlgolVariableStar
EA
Algol (Beta Persei)-type eclipsing systems. Binaries with spherical or slightly ellipsoidal components. It is possible to specify, for their light curves, the moments of the beginning and end of the eclipses. Between eclipses the light remains almost constant or varies insignificantly because of reflection effects, slight ellipsoidality of components, or physical variations. Secondary minima may be absent. An extremely wide range of periods is observed, from 0.2 to >= 10000 days. Light amplitudes are also quite different and may reach several magnitudes.
eclipsing##binary##star##algol##beta##persei##stars##binaries
ALGOL VARIABLE STARS
beta persei stars
Algol Eclipsing Binary
Al*
BOK GLOBULES
Bok Globule
bok##globule
Globules
Bok globules
BokGlobules
Stars
Star
Stellar Object
STELLAR
Stellar
Stars
*
STARS
*
stellar##object##objects
Radio Metric
radio##metric##m
HB*
HorizontalBranchStars
HORIZONTAL BRANCH STARS
hb##star##horizontal##branch
HB*
Stars, horizontal branch
Horizontal-branch Star
LATE TYPE STARS
Stars, cyanogen
late##type##star##latetype##stars
cool stars
Stars, late-type
Star of the late spectral types
Stars:late-type
LateTypeStars
Late-type Star
Stars, carbon
Stars, S
ExtremeUltravioletRadiation
EUV
EXTREME ULTRAVIOLET RADIATION
lpv##long##period##variable##variables##stars##star
LongPeriodVariableStars
Long-period Variable
LONG PERIOD VARIABLE STARS
Cataclysmic Variable Star AM Her type
AmHerculisStars
AM CANUM VENATICORUM STARS
AM
polars
AM Herculis
AM*
am##herculis##cataclysmic##variable##star##stars##amherculis##variables
AMHer
Red*
Red
Red Object
red
red##object
RotV*Ell
EllipsoidalVariableStar
ELLIPSOIDAL VARIABLE STARS
Rotating ellipsoidal variables (b Per, Alpha Vir). These are close binary systems with ellipsoidal components, which change combined brightnesses with periods equal to those of orbital motion because of changes in emitting areas toward an observer, but showing no eclipses. Light amplitudes do not exceed 0.1 mag in V.
ellipsoidal##variable##star##variables##stars
Ellipsoidal Variable Star
ELL
El*
ACCRETION
Accretion
Accretion
accretion##accreting##process##processes
IV
Supernova type Ic
supernova##supernovae##super##nova##novae##sn##typeic##type1c##type##1c##ic##c##1##i
RADIO QUIET QUASARS
high##power##radio##quiet##agn##active##galaxy##nucleus##nuclei##quasar##quasi##stellar##quasistellar##object##objects##qso##qsos
Quasars: general
High-power Radio-quiet AGN
QSOs
QSOs
Quasars
quasi stellar objects
QSO
QUASARS
QSOs
DOUBLE QUASARS
RadioQuietQuasars
DoubleQuasars
QSO
qso
quasi stellar galaxies
QSO
QSO
quasi stellar radio sources
Multiple_Stars
multiple##star##stars##system
MultipleStars
Multiple Star
A system of two or more distinct stars
triple stars
**
MULTIPLE STARS
2
Stars, double and multiple
Double or multiple star
supernova##supernovae##super##nova##novae##sn##typeiilp##type2lp##type##2##iilpb##typeii##type2
Supernova type IILP
EarlyTypeStars
EARLY TYPE STARS
hot stars
Star of the early spectral types
EARLY TYPE EMISSION STARS
Stars, OB
early##type##star##earlytype##stars
Stars:early-type
EarlyTypeEmissionStars
Early-type Star
blue stars
HI
warm##hi##region##regions
HI Region Warm
HI
HII_G
hii####galaxy##gal##galaxies##g
HII Galaxy
H2G
BwStars
Stars, Ap
PECULIAR STARS
Pe*
Peculiar Stellar Object
Stars, Am
AmStars
PeculiarStars
Am STARS
Stars, peculiar
Pec*
Stars:peculiar
ApStars
peculiar##star##stellar##object
Stars, metal-deficient
Bw STARS
Ap STARS
Stars, Bp
Stars, barium
Halo
Halos
halo
HALOS
REFLECTION
Reflection Process
Reflection
Reflection of stellar light
reflection##process##processes
eruptive##variable##star##stars##variables
Eruptive Variable Star
ERUPTIVE BINARY STARS
Eruptive variables are stars varying in brightness because of violent processes and flares occurring in their chromospheres and coronae. The light changes are usually accompanied by shell events or mass outflow in the form of stellar winds of variable intensity and/or by interaction with the surrounding interstellar medium.
eruptive variable stars
Er*
explosive variable stars
EruptiveBinaryStars
Eruptive*
eruptive stars
pulsating##variable##star##variables##stars
Pulsating variables are stars showing periodic expansion and contraction of their surface layers. The pulsations may be radial or nonradial. A radially pulsating star remains spherical in shape, while in the case of nonradial pulsations the star's shape periodically deviates from a sphere, and even neighboring zones of its surface may have opposite pulsation phases.
Depending on the period value, on the mass and evolutionary status of the star, and on the scale of pulsational phenomena, different types of pulsating variables may be distinguished.
Pulsating Star
PulsatingVariableStars
PulsV*
PULSATING VARIABLE STARS
Pu*
Pulsating Variable Star
supernova##supernovae##super##nova##novae##sn##typeia##type1b##type##1b##ib##b##1##i
Supernova type Ib
compound##object##morphology
Compound Object Morphology
Binaries:cataclysmic
Binaries, cataclysmic
cataclysmic##variable##star##stars##binaries##binary##double##cv##variables
cataclysmic binary stars
CATACLYSMIC VARIABLE STARS
Cataclysmic Variable
CataclysmicVariableStars
Variable stars showing outbursts caused by thermonuclear burst processes in their surface layers (novae) or deep in their interiors (supernovae). We use the term "novalike" for variables that show novalike outbursts caused by rapid energy release in the surrounding space (UG-type stars) and also for objects not displaying outbursts but resembling explosive variables at minimum light by their spectral (or other) characteristics. The majority of explosive and novalike variables are close binary systems, their components having strong mutual influence on the evolution of each star. It is often observed that the hot dwarf component of the system is surrounded by an accretion disk formed by matter lost by the other, cooler, and more extended component.
AM CANUM VENATICORUM STARS
CataclyV*
AmCanumVenaticorumStars
CV
CV*
component of SpaceVelocity
Radial velocities
radial##velocity
RadialVelocity
Radial Velocity
value < 300000
RADIAL VELOCITY
Comets
Comets
COMETS
Comet
Comets
comet##comets
accreting##white##wd##dwarf
Accreting White Dwarf
mR
Radio(m)
Metric Radio Source
radio##source##metric
Eclipse of WUMa Type
eclipse##wuma##w##ursae##majoris##process##processes
Envelope
Envelopes
envelope
ENVELOPES
Type1.5 Seyfert Active Galactic Nucleus
Seyfert 1.5 Galaxy
Seyfert
seyfert1.5##1.5##seyferts##low##power##radio##quiet##agn##active##galaxy##nucleus##seyfert##galactic##nuclei##seyferts
spectrum
Spectrum
Explosion or Eruption process
Explosion or Eruption process
ERUPTIONS
EXPLOSIONS
eruption##explosion##process##processes
Explosions
Eruptions
HypergiantStars
Star of Luminosity Class I
HYPERGIANT STARS
super##giant##supergiant##giants##supergiants
Stars, supergiant
Supergiant
EW
eclipsing##binary##star##wuma##w##ursae##majoris##stars##binaries
Eclipsing Binary of W UMa type
W Ursae Majoris-type eclipsing variables. These are eclipsers with periods shorter than 1 days, consisting of ellipsoidal components almost in contact and having light curves for which it is impossible to specify the exact times of onset and end of eclipses. The depths of the primary and secondary minima are almost equal or differ insignificantly. Light amplitudes are usually <0.8 mag in V. The components generally belong to spectral types F-G and later.
WUMa Eclipsing Binary
EB*WUMa
WU*
galactic##galaxy##morphology##dwarf##barred##spiral
*in**
stellar##object##star##in##double##stars##objects
Stellar Object in Double Star
A star that is part of a double star
*i*
ERO
Extremely Red Object
RedExtreme
extremely##red##object
stellar##object##star##in##association##stars##objects##associations
*iA
*inAssoc
Stellar Object in Association
BrightGalaxies
Galaxies
galaxy##gal##galaxies##g
Galaxies, optical
Galaxy
Galaxies, optical
CompactGalaxies
Galaxies, UV-excess
GALAXY
Galaxies
Galaxies, Markarian
Galaxy
Galaxies
Galaxies, photometry
Galaxies, nearby
Galaxy
COMPACT GALAXIES
GALAXIES
galaxies
G
Galaxy catalogs
G
Galaxies, IR
Galaxies, spectra
Galaxies, rotation
Lensing Process
lensing##process##processes##lens
Gravitational_lensing
Gravitational lensing
GravitationalLenses
GRAVITATIONAL LENSES
Cloud
Interstellar medium
inter##stellar##interstellar##medium##ism
Interstellar medium
interstellar medium
ISM
Neb
Cld
Interstellar_Medium
Neb
pulsating##white##dwarf##wd
ZZ*
Pulsating White Dwarf
PulsWD*
Barred Spiral Galaxy
galactic bars
BarredSpiralGalaxies
barred##spiral##galaxy##gal##galaxies##g
BARRED SPIRAL GALAXIES
AbsoluteMagnitude
ABSOLUTE MAGNITUDE
Absolute Magnitude
absolute##magnitude
Effective Temperature
EFFECTIVE TEMPERATURE
effective##temperature
Effective temperatures
EffectiveTemperature
White dwarfs
WD*
White Dwarf
WHITE DWARF STARS
Stars:white_dwarf
WD
White Dwarf
da stars
white##dwarf##wd
Stars, white dwarf
WhiteDwarfStars
WD*
SupernovaRemnants
SNR
SNR
SNR
supernova##shell##remnant##shells##remnants##snr##supernovae##snrs
Supernova Remnant Shell
SUPERNOVA REMNANTS
Supernova remnants
SNR
SuperNovae_Remnants
White dwarf with metal lines
BDwarfStars
B DWARF STARS
TOP
TOP concept
thing##top##anything
Sub-stellar
su*
sub##substellar##object##objects##stellar
Substellar Object
CW
W Virginis Variable Star
w##virginis##wvirginis##type##variable##star##stars##variables
Variables of the W Virginis type. These are pulsating variables of the galactic spherical component (old disk) population with periods of approximately 0.8 to 35 days and amplitudes from 0.3 to 1.2 mag in V. They obey a period-luminosity relation different from that for Delta Cep variables. For an equal period value, the W Vir variables are fainter than the Delta Cep stars by 0.7 - 2 mag. The light curves of W Vir variables for some period intervals differ from those of Delta Cep variables for corresponding periods either by amplitudes or by the presence of humps on their descending branches, sometimes turning into broad flat maxima. W Vir variables are present in globular clusters and at high galactic latitudes.
Variable Star of W Vir type
WV*
W VIRGINIS STARS
PulsV*WVir
WVirginisStars
Low-mass X-ray binaries (LMXBs) are binary stars where one of the components is either a black hole or neutron star. The other component (donor) is usually filling its Roche lobe and therefore transfers mass to the compact star. The donor is less massive than the compact object, and can be on the main sequence, a degenerate dwarf (white dwarf), or an evolved star (red giant). Found in the Milky Way, external galaxies, and in globular clusters.
A typical LMXB emits almost all of its radiation in X-rays, and typically less than one percent in visible light, so they are among the brightest objects in the X-ray sky, but relatively faint in visible light. The apparent magnitude is typically around 15 to 20. The brightest part of the system is the accretion disk around the compact object. The orbital periods of LMXBs range from ten minutes to hundreds of days. Soft-gamma rays emitters.
x##ray##xray##binary##binaries##low##mass##lmxb##lmxrb
Low-mass X-ray Binary
LXB
LMXB
globular##cluster##star##stars##clusters
Globular Clusters
Globular Cluster
GlCl
Globular_Clusters
GLOBULAR STAR CLUSTERS
Clusters, globular
GlC
GlobularStarClusters
centimetric##radio##source
Centimetric Radio Source
Radio(cm)
cm
RocheLobe
roche##lobe##rochelobe
ROCHE LOBE
Roche Lobe
ASubgiantStars
A SUBGIANT STARS
RI*
Rapid_Irreg_V*
Rapid irregular variables (class: eruptive) having no apparent connection with diffuse nebulae and showing light changes of about 0.5 - 1.0 mag within several hours or days. There is no strict boundary between rapid irregular and Orion variables. If a rapid irregular star is observed in the region of a diffuse nebula, it is considered an Orion variable. To attribute a variable to this type (R.I.), it is necessary to take much care to be certain that its light changes are really not periodic.
Sub-types:
- Rapid irregular variables of the early spectral types, B-A or Ae;
- Rapid irregular variables of the intermediate and late spectral types, F-M and Fe-Me.
rapid##irregular##variable##star##variables##stars
IS
Variable Star with rapid variations
Rapid Irregular Variable Star
space##velocity
Space Velocity
lobe##dominated##lobedominated
Lobe Dominated
Core/Extended Flux Ratio < 1)
Dark Nebula
DNe
dark##cloud##nebula
DarkClouds
DkNeb
Nebulae, dark
DARK CLOUDS
stars
HELIUM POOR STARS
HeliumPoorStars
Stars
Star
star##stars
HELIUM RICH STARS
Star
HeliumRichStars
HYDROGEN DEFICIENT STARS
HydrogenDeficientStars
1
M STARS
M Star
Star of Spectral Type M
MStars
m##star##mstar##mstars##stars
A SUBDWARF STARS
ASubdwarfStars
Surface Brightness
SURFACE BRIGHTNESS
SurfaceBrightness
surface##brightness
for extended objects
FANAROFF RILEY CLASS
fanaroff##riley##type##2##agn#active##nucleus##galactic##type2##nuclei##galaxy
Fanaroff-Riley type II, which is a Type2 Active Galactic Nucleus
Fanaroff-Riley type 2
FanaroffRileyClass
Line Emission
herbig stars
emission##line##lines##process##processes
AeStars
EmissionLines
EMISSION LINES
Ae STARS
White dwarf with metal lines
XRayBinaryStars
X RAY BINARY STARS
X-ray Binary
Close binary systems that are sources of strong, variable X-ray emission and which do not belong to or are not yet attributed to any other type of variable stars. One of the components of the system is a hot compact object (white dwarf, neutron star, or possibly a black hole). X-ray emission originates from the infall of matter onto the compact object or onto an accretion disk surrounding the compact object. In turn, the X-ray emission is incident upon the atmosphere of the cooler companion of the compact object and is reradiated in the form of optical high-temperature radiation (reflection effect), thus making that area of the cooler companion's surface an earlier spectral type.
x##ray##xray##binary##binaries##stars##xb##xrb
X
XB
XRB
XB*
Binaries, X-ray
BETA LYRAE STARS
eclipsing##binary##star##beta##lyrae##stars##binaries
EB*betLyr
Beta Lyrae Eclipsing Binary
BetaLyraeStars
Eclipsing Binary of Beta Lyr type
Beta Lyrae-type eclipsing systems. These are eclipsing systems having ellipsoidal components and light curves for which it is impossible to specify the exact times of onset and end of eclipses because of a continuous change of a system's apparent combined brightness between eclipses; secondary minimum is observed in all cases, its depth usually being considerably smaller than that of the primary minimum; periods are mainly longer than 1 day. The components generally belong to early spectral types (B-A). Light amplitudes are usually <2 mag in V.
EB
bL*
galactic##galaxy##morphology##giant
o##star##ostar##stars##ostars
O STARS
Stars, O
O Star
Star of Spectral Type O
OStars
binaries
**
2
EruptiveBinaryStar
wide binary stars
double stars
BinaryStars
Double or multiple star
binary systems
DetachedBinaryStars
DETACHED BINARY STARS
BINARY STARS
CONTACT BINARY STARS
double##star##pair
ContactBinaryStars
**
Double Star
ERUPTIVE BINARY STARS
A system of two stars
herbig stars
Star of Spectral Type A
A Star
AeStars
AmStars
A STARS
Ae STARS
ApStars
AStars
a##star##astar##stars##astars
Ap STARS
Stars, A-type
Indicates that the DOMAIN CompoundObject has the RANGE AstrObject among its direct physical components (the RANGE AstrObject cannot be a component of a component of the composite object)
has among its (direct) components
is class of
Indicates that the RANGE AstroPortion can be found whithin the DOMAIN CompoundObject or AstroPortion
Indicates that the RANGE AstroPortion can be found whithin the DOMAIN CompoundObject or AstroPortion
features a noticeable emission in
is a member of the class:
has among its processes
Indicates that an astronomical object is the location of a Process/has an attached process
features absorption spectral line(s) for
is ionized by
Indicates what ionizes the gas of a given ISM
is morphology of
Indicates that the DOMAIN AstrObject is a direct physical component of the RANGE CompositeObject (not a component of a component of the RANGE CompositeObject)
is component of
has among its morphological features
features emission spectral line(s) for
Indicates that the DOMAIN AstrObject has the RANGE Measurement among its (observational) measurements
has among its measurements
features an abundance of
has for progenitor
Indicates the Progenitor of a Supernova
is portion of
is measured for
keywords for various purposes like plain text search
name in natural language for display purposes
morphological type for galaxies in SIMBAD
Standard name in Simbad's object classification
Main part of the spectral type in SIMBAD (letters only, found at the beginning of SIMBAD's spectral type value)
Text definition of a concept, as complete as possible
VizieR keyword corresponding to an item of the ontology
Main part of the luminosity class in SIMBAD (letters only, found within SIMBAD's spectral type value after said spectral type)
Astronomical Data Center keyword
NED object type code
tests that should be taken care of outside of the ontology (e.g. check that a value is within sensible boundaries)
any kind of comment on an element of the ontology
General Catalogue of Variable Stars code corresponding to a concept of the ontology
non-standardized keywords used in registry subjects
Short code in Simbad's object classification
default instance
default instance
default instance
default instance
default instance
default instance