Terrestrial Time

E116186

Terrestrial Time is a modern astronomical time standard used for precise calculations of planetary motion and ephemerides, defined in relation to atomic time rather than Earth's rotation.

All labels observed (3)

How this entity was disambiguated

Statements (47)

Predicate Object
instanceOf astronomical time scale ⓘ
time standard ⓘ
abbreviation TT ⓘ
basedOn atomic time ⓘ
basisOf Barycentric Coordinate Time transformations ⓘ
Barycentric Dynamical Time ⓘ
category astronomy ⓘ
celestial mechanics ⓘ
timekeeping ⓘ
continuity continuous without leap seconds ⓘ
coordinateType proper time of a clock on the geoid ⓘ
definedBy International Astronomical Union ⓘ
definedIn IAU 1991 Resolution A4 ⓘ
distinctFrom Greenwich Mean Time ⓘ
Local civil time ⓘ
Universal Time 1 ⓘ
Universal Time 2 ⓘ
epochOffsetDefinedAt 1977-01-01T00:00:00 TAI ⓘ
epochOffsetValue TT = TAI + 32.184 s ⓘ
follows International Atomic Time ⓘ
frame geocentric reference frame ⓘ
governingTheory general relativity ⓘ
maintainedBy timekeeping and astronomical institutions ⓘ
notBasedOn Earth rotation ⓘ
offsetFromTAI 32.184 seconds ⓘ
precision suitable for relativistic timekeeping ⓘ
primaryUseDomain solar system ephemeris construction ⓘ
referenceLocation Earth geocenter ⓘ
geoid ⓘ
refinedIn IAU 2000 resolutions ⓘ
IAU 2006 resolutions ⓘ
relatedTo Coordinated Universal Time ⓘ
International Atomic Time ⓘ
Universal Time ⓘ
linked to: GMT
replaced Terrestrial Dynamical Time ⓘ
linked to: Terrestrial Time
scaleType coordinate time scale ⓘ
status current standard for geocentric astronomical timekeeping ⓘ
successorOf Ephemeris Time ⓘ
Terrestrial Dynamical Time ⓘ
linked to: Terrestrial Time
symbol T_T ⓘ
timeUnit SI second ⓘ
usedFor ephemerides ⓘ
high-precision astronomical observations ⓘ
lunar motion calculations ⓘ
planetary motion calculations ⓘ
solar system dynamics ⓘ
spacecraft navigation ⓘ

How these facts were elicited

Referenced by (11)

Full triples — surface form annotated when it differs from this entity's canonical label.

Terrestrial Time → replaced → Terrestrial Dynamical Time ⓘ
linked to: Terrestrial Time
Terrestrial Time → successorOf → Terrestrial Dynamical Time ⓘ
linked to: Terrestrial Time
IAU 1991 Resolution A4 → defines → Terrestrial Time ⓘ
Ephemeris Time → replacedBy → Terrestrial Dynamical Time ⓘ
linked to: Terrestrial Time
Ephemeris Time → replacedBy → Terrestrial Time ⓘ
Ephemeris Time → relatedTo → Terrestrial Time ⓘ
Barycentric Dynamical Time → closelyMatches → Terrestrial Time ⓘ
IAU 2000 resolutions → concerns → Terrestrial Time ⓘ
IAU 2006 resolutions → concerns → Terrestrial Time ⓘ
IAU 2006 resolutions → refines → Terrestrial Time scale ⓘ
linked to: Terrestrial Time