gives the value of the property prop about the orientation of the Earth on the given date.
gives the specified variant of the property prop on the given date.
- GeoOrientationData gives information about the orientation of the Earth with respect to the celestial reference frame.
- GeoOrientationData is typically used in applications such as pointing a telescope, monitoring the rotation and wobble of the Earth, or investigating how Earth's rotation has slowed down in the past.
- The gravitational pull of other celestial bodies, the internal motion of mass in the Earth, ocean tides and other physical phenomena modify the average rotation of the Earth and the direction of its rotation axis in unpredictable ways. The consequences of many of those effects are tracked in GeoOrientationData.
- In GeoOrientationData[date,…], date specifications are DateObject or DateInterval expressions representing dates or intervals in the UTC time system.
- Temporal properties describing the inhomogeneous duration of the day include:
"DayDuration" duration in seconds of the day of the given date "DayDurationExcess" excess of the duration of the day over 86400 seconds "LeapSecondCount" number of leap seconds inserted until the given date "LeapSeconds" list of leap seconds added during a given period "TAIMinusUT1" difference between TAI and UT1 times "TAIMinusUTC" difference between TAI and UTC times "UT1MinusUTC" difference between UT1 and UTC times
- Properties describing the orientation of the Earth with respect to the terrestrial reference frame include:
"PolarMotion" components of the rotation axis in the ITRF frame "PolarMotionX" component of rotation axis, positive toward Greenwich "PolarMotionY" component of rotation axis, positive toward 90° west "PolarMotionGeoPosition" geodetic location of the instantaneous rotation axis
- Properties describing the orientation of the Earth with respect to the celestial reference frame include:
"BiasMatrix" rotation matrix from the ICRF frame to the mean equatorial frame of J2000 "PrecessionMatrix" rotation matrix from the mean equatorial frame of J2000 to the mean equatorial frame of date "NutationMatrix" rotation matrix from the mean equatorial frame of date to the true equatorial frame of date "Obliquity" obliquity angle between the equatorial and ecliptic planes
- In GeoOrientationData[date,prop,"variant"] possible variants include:
"Value" value of the property, a number, quantity or geo position "Uncertainty" uncertainty of the measured value, if available "Around" Around[value,uncertainty] object
- For dates after 1960 until April 2021, measured data was obtained from the International Earth Rotation and Reference Systems Service (IERS), as well as predicted data from May 2021 to April 2022. Data before 1960 was obtained from the analysis of older astronomical sources, in particular, ancient observation of eclipses. Future data is extrapolated.
Examplesopen allclose all
Basic Examples (3)
Specify dates as DateObject expressions:
Get a time series of property values for a DateInterval input:
Properties & Relations (3)
Wolfram Research (2021), GeoOrientationData, Wolfram Language function, https://reference.wolfram.com/language/ref/GeoOrientationData.html.
Wolfram Language. 2021. "GeoOrientationData." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/GeoOrientationData.html.
Wolfram Language. (2021). GeoOrientationData. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/GeoOrientationData.html