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2. Earth's orbit - Wikipedia

   en.wikipedia.org/wiki/Earth's_orbit

   The point towards which the Earth in its solar orbit is directed at any given instant is known as the "apex of the Earth's way". [4] [5] From a vantage point above the north pole of either the Sun or Earth, Earth would appear to revolve in a counterclockwise direction around the Sun. From the same vantage point, both the Earth and the Sun would ...

3. Newcomb's Tables of the Sun - Wikipedia

   en.wikipedia.org/wiki/Newcomb's_Tables_of_the_Sun

   The bulk of the work, however, is a collection of tabulated precomputed values that provide the position of the sun at any point in time. Newcomb's Tables were the basis for practically all ephemerides of the Sun published from 1900 through 1983, including the annual almanacs of the U.S. Naval Observatory and the Royal Greenwich Observatory.

4. Earth's rotation - Wikipedia

   en.wikipedia.org/wiki/Earth's_rotation

   Earth's movement along its nearly circular orbit while it is rotating once around its axis requires that Earth rotate slightly more than once relative to the fixed stars before the mean Sun can pass overhead again, even though it rotates only once (360°) relative to the mean Sun. [n 5] Multiplying the value in rad/s by Earth's equatorial ...

5. Orbital speed - Wikipedia

   en.wikipedia.org/wiki/Orbital_speed

   In gravitationally bound systems, the orbital speed of an astronomical body or object (e.g. planet, moon, artificial satellite, spacecraft, or star) is the speed at which it orbits around either the barycenter (the combined center of mass) or, if one body is much more massive than the other bodies of the system combined, its speed relative to the center of mass of the most massive body.

6. Earth orientation parameters - Wikipedia

   en.wikipedia.org/wiki/Earth_Orientation_Parameters

   Due to the very slow pole motion of the Earth, the Celestial Ephemeris Pole (CEP, or celestial pole) does not stay still on the surface of the Earth.The Celestial Ephemeris Pole is calculated from observation data, and is averaged, so it differs from the instantaneous rotation axis by quasi-diurnal terms, which are as small as under 0.01" (see [6]).

7. Speed of gravity - Wikipedia

   en.wikipedia.org/wiki/Speed_of_gravity

   Putting the Sun immobile at the origin, when the Earth is moving in an orbit of radius R with velocity v presuming that the gravitational influence moves with velocity c, moves the Sun's true position ahead of its optical position, by an amount equal to vR/c, which is the travel time of gravity from the sun to the Earth times the relative ...

8. Galactic year - Wikipedia

   en.wikipedia.org/wiki/Galactic_year

   The Solar System is traveling at an average speed of 230 km/s (828,000 km/h) or 143 mi/s (514,000 mph) within its trajectory around the Galactic Center, [3] a speed at which an object could circumnavigate the Earth's equator in 2 minutes and 54 seconds; that speed corresponds to approximately 1/1300 of the speed of light.

9. Kepler's laws of planetary motion - Wikipedia

   en.wikipedia.org/wiki/Kepler's_laws_of_planetary...

   Planets are pushed around the Sun by a force from the Sun. This false assumption relies on incorrect Aristotelian physics that an object needs to be pushed to maintain motion. The propelling force from the Sun is inversely proportional to the distance from the Sun. Kepler reasoned this, believing that gravity spreading in three dimensions would ...