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  2. Earth's rotation - Wikipedia

    en.wikipedia.org/wiki/Earth's_rotation

    Earth's rotation axis moves with respect to the fixed stars (inertial space); the components of this motion are precession and nutation. It also moves with respect to Earth's crust; this is called polar motion. Precession is a rotation of Earth's rotation axis, caused primarily by external torques from the gravity of the Sun, Moon and other bodies.

  3. International Earth Rotation and Reference Systems Service

    en.wikipedia.org/wiki/International_Earth...

    The Sub-bureau for Rapid Service and Predictions of Earth Orientation Parameters of the IERS, located at the United States Naval Observatory, monitors the Earth's rotation. Part of its mission involves the determination of a time scale based on the current rate of the rotation of the Earth. Other services of IERS are at the Paris Observatory.

  4. Earth orientation parameters - Wikipedia

    en.wikipedia.org/wiki/Earth_Orientation_Parameters

    Universal time tracks the Earth's rotation in time, which performs one revolution in about 24 hours. The Earth's rotation is uneven, so UT is not linear with respect to atomic time. It is practically proportional to the sidereal time, which is also a direct measure of Earth rotation. The excess revolution time is called length of day (LOD).

  5. Geosynchronous orbit - Wikipedia

    en.wikipedia.org/wiki/Geosynchronous_orbit

    Animation (not to scale) showing geosynchronous satellite orbiting the Earth. A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbital period means that, for ...

  6. Sidereal time - Wikipedia

    en.wikipedia.org/wiki/Sidereal_time

    In this frame of reference, Earth's rotation is close to constant, but the stars appear to rotate slowly with a period of about 25,800 years. It is also in this frame of reference that the tropical year (or solar year), the year related to Earth's seasons, represents one orbit of Earth around the Sun. The precise definition of a sidereal day is ...

  7. Google Earth - Wikipedia

    en.wikipedia.org/wiki/Google_Earth

    Google Earth is a web and computer program that renders a 3D representation of Earth based primarily on satellite imagery.The program maps the Earth by superimposing satellite images, aerial photography, and GIS data onto a 3D globe, allowing users to see cities and landscapes from various angles.

  8. Comparison of web map services - Wikipedia

    en.wikipedia.org/wiki/Comparison_of_web_map_services

    Google Maps Bing Maps MapQuest Mapy.cz OpenStreetMap Here WeGo Apple Maps Yandex Maps; Degrees of motion Vertical, horizontal, depth, rotation (beta), 360 panoramic (Street View), 3D mode (Google Earth JavaScript) Vertical, horizontal, depth, 360 panoramic (Streetside), 3D mode (tilt, pan, rotate) Vertical, horizontal, depth

  9. Inner core super-rotation - Wikipedia

    en.wikipedia.org/wiki/Inner_core_super-rotation

    The new estimate for super-rotation was reduced to 0.2–0.3° per year. [23] Inner core rotation has also been estimated using PKiKP waves, which scatter off the surface of the inner core, rather than PKP(DF) waves. Estimates using this method have ranged from 0.05 to 0.15° per year. [2]