enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Earth's orbit - Wikipedia

    en.wikipedia.org/wiki/Earth's_orbit

    Ignoring the influence of other Solar System bodies, Earth's orbit, also called Earth's revolution, is an ellipse with the EarthSun barycenter as one focus with a current eccentricity of 0.0167. Since this value is close to zero, the center of the orbit is relatively close to the center of the Sun (relative to the size of the orbit).

  3. 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.

  4. Orders of magnitude (speed) - Wikipedia

    en.wikipedia.org/wiki/Orders_of_magnitude_(speed)

    Escape speed from Earth by NASA New Horizons spacecraft—Fastest escape velocity. 17,000: 61,000: 38,000 0.00006: The approximate speed of the Voyager 1 probe relative to the Sun, when it exited the Solar System. [25] 29,800: 107,280: 66,700 0.00010: Speed of the Earth in orbit around the Sun. 47,800: 172,100: 106,900 0.00016

  5. Angular diameter - Wikipedia

    en.wikipedia.org/wiki/Angular_diameter

    Thus, the angular diameter of Earth's orbit around the Sun as viewed from a distance of 1 pc is 2″, as 1 AU is the mean radius of Earth's orbit. The angular diameter of the Sun, from a distance of one light-year, is 0.03″, and that of Earth 0.0003″. The angular diameter 0.03″ of the Sun given above is approximately the same as that of a ...

  6. Sun-synchronous orbit - Wikipedia

    en.wikipedia.org/wiki/Sun-synchronous_orbit

    An orbit will be Sun-synchronous when the precession rate ρ = ⁠ dΩ / dt ⁠ equals the mean motion of the Earth about the Sun n E, which is 360° per sidereal year (1.990 968 71 × 10 −7 rad/s), so we must set n E = ⁠ ΔΩ E / T E ⁠ = ρ = ⁠ ΔΩ / T ⁠, where T E is the Earth orbital period, while T is the period of the spacecraft ...

  7. Astronomical unit - Wikipedia

    en.wikipedia.org/wiki/Astronomical_unit

    This is because the distance between Earth and the Sun is not fixed (it varies between 0.983 289 8912 and 1.016 710 3335 au) and, when Earth is closer to the Sun , the Sun's gravitational field is stronger and Earth is moving faster along its orbital path. As the metre is defined in terms of the second and the speed of light is constant for all ...

  8. Ecliptic - Wikipedia

    en.wikipedia.org/wiki/Ecliptic

    The actual speed with which Earth orbits the Sun varies slightly during the year, so the speed with which the Sun seems to move along the ecliptic also varies. For example, the Sun is north of the celestial equator for about 185 days of each year, and south of it for about 180 days. [7] The variation of orbital speed accounts for part of the ...

  9. Kepler's laws of planetary motion - Wikipedia

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

    The Sun is approximately at the center of the orbit. The speed of the planet in the main orbit is constant. Despite being correct in saying that the planets revolved around the Sun, Copernicus was incorrect in defining their orbits.