local standard of rest
E581533
The local standard of rest is a reference frame in the Milky Way that represents the average motion of stars in the Sun’s neighborhood, used to measure stellar and galactic velocities.
Statements (50)
| Predicate | Object |
|---|---|
| instanceOf |
astrophysical reference frame
ⓘ
galactic dynamical concept ⓘ kinematic standard of rest ⓘ |
| alsoKnownAs | LSR ⓘ |
| appliesTo | solar neighborhood stars ⓘ |
| associatedWith |
Galactic coordinate system
NERFINISHED
ⓘ
Galactic rotation ⓘ Oort constants NERFINISHED ⓘ solar neighborhood ⓘ |
| assumes | nearby stars have small random motions around LSR ⓘ |
| belongsTo | Milky Way disk NERFINISHED ⓘ |
| coordinateSystem | Galactic coordinates ⓘ |
| definedAs | average motion of stars in the Sun’s neighborhood ⓘ |
| definedBy | mean motion of stars in a specified volume around the Sun ⓘ |
| definedInContextOf | Milky Way galaxy NERFINISHED ⓘ |
| frameVelocityOfSunApprox | (U,V,W) ≈ (11, 12, 7) km/s relative to LSR ⓘ |
| hasAssumption | Sun is near circular orbit around Galactic center ⓘ |
| hasHistoricalUse | standardizing radial velocity measurements in spectroscopy ⓘ |
| hasLimitation |
depends on sample of stars used
ⓘ
local approximation, not valid for whole Galaxy ⓘ not unique; different definitions exist ⓘ |
| hasType |
local reference frame
ⓘ
non-inertial frame ⓘ |
| hasVariant |
dynamical local standard of rest
ⓘ
kinematic local standard of rest ⓘ |
| hasVelocityComponent |
U (toward Galactic center)
ⓘ
V (in direction of Galactic rotation) ⓘ W (toward north Galactic pole) ⓘ |
| relatedConcept |
Galactic standard of rest
ⓘ
International Celestial Reference System NERFINISHED ⓘ barycentric reference frame ⓘ heliocentric reference frame ⓘ |
| relativeTo |
Sun
NERFINISHED
ⓘ
nearby stars ⓘ |
| timeScale | assumed steady over tens of millions of years ⓘ |
| usedFor |
correcting observed stellar velocities for solar motion
ⓘ
defining standard radial velocity zero point ⓘ interpreting gas motions in the Milky Way ⓘ mapping spiral structure of the Galaxy ⓘ studying Galactic rotation curve ⓘ transforming heliocentric velocities to Galactic frame ⓘ |
| usedIn |
astrometry
ⓘ
galactic astronomy ⓘ galactic dynamics ⓘ radio astronomy ⓘ stellar kinematics ⓘ |
| usedToMeasure |
galactic velocities
ⓘ
proper motions ⓘ radial velocities ⓘ stellar velocities ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.