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  2. Kármán line - Wikipedia

    en.wikipedia.org/wiki/Kármán_line

    Earth's atmosphere photographed from the International Space Station.The orange and green line of airglow is at roughly the altitude of the Kármán line. [1]The Kármán line (or von Kármán line / v ɒ n ˈ k ɑːr m ɑː n /) [2] is a conventional definition of the edge of space.

  3. Outer space - Wikipedia

    en.wikipedia.org/wiki/Outer_space

    The energy required to reach Earth orbital velocity at an altitude of 600 km (370 mi) is about 36 MJ/kg, which is six times the energy needed merely to climb to the corresponding altitude. [93] The escape velocity required to pull free of Earth's gravitational field altogether and move into interplanetary space is about 11.2 km/s (25,100 mph).

  4. Atmospheric refraction - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_refraction

    Atmospheric refraction of the light from a star is zero in the zenith, less than 1′ (one arc-minute) at 45° apparent altitude, and still only 5.3′ at 10° altitude; it quickly increases as altitude decreases, reaching 9.9′ at 5° altitude, 18.4′ at 2° altitude, and 35.4′ at the horizon; [4] all values are for 10 °C and 1013.25 hPa ...

  5. 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.

  6. Extremes on Earth - Wikipedia

    en.wikipedia.org/wiki/Extremes_on_Earth

    As the Dead Sea waters are receding, the water surface level drops more than 1 metre (3.3 ft) per year. [35] The point on the atmospheric surface closest to the Earth's centre (interpreted as a natural surface of the land or sea that is accessible by a person) is the surface of the Arctic Ocean at the Geographic North Pole (6,356.77 km or 3,950 ...

  7. Low Earth orbit - Wikipedia

    en.wikipedia.org/wiki/Low_Earth_orbit

    A wide variety of sources [5] [6] [7] define LEO in terms of altitude.The altitude of an object in an elliptic orbit can vary significantly along the orbit. Even for circular orbits, the altitude above ground can vary by as much as 30 km (19 mi) (especially for polar orbits) due to the oblateness of Earth's spheroid figure and local topography.

  8. Planetshine - Wikipedia

    en.wikipedia.org/wiki/Planetshine

    Leonardo da Vinci explained the phenomenon in the early 16th century when he realized that both Earth and the Moon reflect sunlight at the same time. Light is reflected from Earth to the Moon and back to Earth as earthshine. Earthshine is used to help determine the current albedo of Earth.

  9. Outgoing longwave radiation - Wikipedia

    en.wikipedia.org/wiki/Outgoing_longwave_radiation

    Thus, any energy that enters a system but does not leave must be retained within the system. So, the amount of energy retained on Earth (in Earth's climate system) is governed by an equation: [change in Earth's energy] = [energy arriving] − [energy leaving]. Energy arrives in the form of absorbed solar radiation (ASR). Energy leaves as ...