Statements (122)
| Predicate | Object |
|---|---|
| gptkbp:instanceOf |
variable star
stellar classification type of variable star variable star type |
| gptkbp:affects |
Light curve
|
| gptkbp:ageRange |
less than 1 million years
|
| gptkbp:alsoKnownAs |
FUor
RCB variable |
| gptkbp:alternativeName |
BL_Herculis_variable
Cepheid_variable FU_Orionis_variable RR_Lyrae_variable RS_Canum_Venaticorum_variable R_Coronae_Borealis_variable Variable_star cataclysmic_variable_star luminous_blue_variable |
| gptkbp:amplitude |
up to 1.5 magnitudes
|
| gptkbp:associatedWith |
young stellar objects
accretion disks |
| gptkbp:brightnessDropCause |
carbon dust cloud formation
|
| gptkbp:brightnessIncrease |
up to 6 magnitudes
|
| gptkbp:carbonContent |
carbon-rich
|
| gptkbp:cataloguedIn |
gptkb:General_Catalogue_of_Variable_Stars
|
| gptkbp:category |
gptkb:eruptive_variable_stars
pre-main-sequence variable stars |
| gptkbp:commonIn |
old stellar populations
|
| gptkbp:defines |
A star whose brightness as seen from Earth fluctuates.
|
| gptkbp:discoveredBy |
gptkb:Williamina_Fleming
gptkb:John_Goodricke gptkb:Edward_Pigott 1899 1936 early 20th century |
| gptkbp:discoveredIn |
1784
1795 |
| gptkbp:distance |
yes
|
| gptkbp:evolutionaryStage |
horizontal branch
|
| gptkbp:evolvesFrom |
final helium shell flash
white dwarf merger |
| gptkbp:example |
gptkb:V1515_Cygni
gptkb:Mira_variable gptkb:R_Coronae_Borealis Eclipsing binary variable star V1057 Cygni V1735 Cygni V346 Nor Z CMa RY Sagittarii V854 Centauri |
| gptkbp:field |
Astronomy
|
| gptkbp:foundIn |
gptkb:galaxy
gptkb:Population_II_stars globular clusters star-forming regions |
| gptkbp:hasProperty |
Luminosity variation
Periodicity |
| gptkbp:hasType |
Extrinsic variable star
Intrinsic variable star |
| gptkbp:heliumContent |
helium-rich
|
| gptkbp:heliumFusion |
core
|
| gptkbp:hydrogenContent |
hydrogen-deficient
|
| gptkbp:light_curve_shape |
asymmetric
|
| gptkbp:lightCurveFeature |
slow recovery
sudden deep declines |
| gptkbp:lightCurveShape |
sawtooth
|
| gptkbp:location |
gptkb:galaxy
gptkb:Milky_Way globular clusters pre-main-sequence stars |
| gptkbp:luminosity |
~40-50 solar luminosities
|
| gptkbp:luminosity_class |
gptkb:giant
|
| gptkbp:mass |
~0.6-0.8 solar masses
|
| gptkbp:measures |
gptkb:Spectroscopy
Photometry |
| gptkbp:metallicity |
low
|
| gptkbp:namedAfter |
gptkb:BL_Herculis
gptkb:R_Coronae_Borealis gptkb:RR_Lyrae FU Orionis |
| gptkbp:numberKnown |
~100
|
| gptkbp:observedBy |
gptkb:AAVSO
optical wavelengths infrared wavelengths |
| gptkbp:outburstCause |
sudden increase in accretion rate
|
| gptkbp:outburstDuration |
decades
|
| gptkbp:period |
0.2 to 1 day
|
| gptkbp:period_range |
1 to 4 days
|
| gptkbp:periodLuminosityRelation |
exists
|
| gptkbp:prototype |
FU Orionis
|
| gptkbp:pulsation_mechanism |
radial pulsation
|
| gptkbp:relatedTo |
RV Tauri variable
W Virginis variable |
| gptkbp:restored |
months to years
|
| gptkbp:spectralType |
A
F A to F F or G supergiant-like F or G supergiant |
| gptkbp:stellarPopulation |
gptkb:Population_II
|
| gptkbp:studiedBy |
Astronomers
|
| gptkbp:subclassOf |
gptkb:star
gptkb:Type_II_Cepheid_variable |
| gptkbp:subspecies |
gptkb:RRab
gptkb:RRc gptkb:RRd |
| gptkbp:typicalAmplitude |
0.3 to 2 magnitudes
|
| gptkbp:typicalBrightnessDrop |
up to 9 magnitudes
|
| gptkbp:typicalMass |
0.3 to 2 solar masses
|
| gptkbp:usedFor |
distance indicators
distance measurement standard candle |
| gptkbp:variableType |
pulsating variable
|
| gptkbp:variant |
irregular
eruptive variable |
| gptkbp:bfsParent |
gptkb:Nord
gptkb:Stars gptkb:Polaris gptkb:The_North_Star gptkb:Nova |
| gptkbp:bfsLayer |
5
|