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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. 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.

  4. Satellite ground track - Wikipedia

    en.wikipedia.org/wiki/Satellite_ground_track

    The "ground track" in this case consists of a single point on the Earth's equator, above which the satellite sits at all times. Note that the satellite is still orbiting the Earth — its apparent lack of motion is due to the fact that the Earth is rotating about its own center of mass at the same rate as the satellite is orbiting.

  5. Geostationary orbit - Wikipedia

    en.wikipedia.org/wiki/Geostationary_orbit

    where F g is the gravitational force acting between two objects, M E is the mass of the Earth, 5.9736 × 10 24 kg, m s is the mass of the satellite, r is the distance between the centers of their masses, and G is the gravitational constant, (6.674 28 ± 0.000 67) × 10 −11 m 3 kg −1 s −2.

  6. Sidereal time - Wikipedia

    en.wikipedia.org/wiki/Sidereal_time

    The Earth rotation angle (ERA) measures the rotation of the Earth from an origin on the celestial equator, the Celestial Intermediate Origin, also termed the Celestial Ephemeris Origin, [9] that has no instantaneous motion along the equator; it was originally referred to as the non-rotating origin. This point is very close to the equinox of J2000.

  7. 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

  8. South-up map orientation - Wikipedia

    en.wikipedia.org/wiki/South-up_map_orientation

    South-up map orientation is the orientation of a map with south up, at the top of the map, amounting to a 180-degree rotation of the map from the standard convention of north-up. Maps in this orientation are sometimes called upside down maps or reversed maps .

  9. 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.