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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; it is widely but not universally accepted.

  3. List of orbits - Wikipedia

    en.wikipedia.org/wiki/List_of_orbits

    This works out to an altitude of 35,786 km (22,236 mi). Both complete one full orbit of Earth per sidereal day (relative to the stars, not the Sun). High Earth orbit: geocentric orbits above the altitude of geosynchronous orbit (35,786 km or 22,236 mi). [8] For Earth orbiting satellites below the height of about 800 km, the atmospheric drag is ...

  4. 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.

  5. Thermosphere - Wikipedia

    en.wikipedia.org/wiki/Thermosphere

    The density of the Earth's atmosphere decreases nearly exponentially with altitude. The total mass of the atmosphere is M = ρ A H ≃ 1 kg/cm 2 within a column of one square centimeter above the ground (with ρ A = 1.29 kg/m 3 the atmospheric density on the ground at z = 0 m altitude, and H ≃ 8 km the average atmospheric scale height).

  6. Solar irradiance - Wikipedia

    en.wikipedia.org/wiki/Solar_irradiance

    The solar flux density (insolation) onto a plane tangent to the sphere of the Earth, but above the bulk of the atmosphere (elevation 100 km or greater) is: = {⁡ ⁡ > ⁡ () The average of Q over a day is the average of Q over one rotation, or the hour angle progressing from h = π to h = −π : Q ¯ day = − 1 2 π ∫ π − π Q d h ...

  7. 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 ...

  8. Orders of magnitude (length) - Wikipedia

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

    Approximately one light-minute: 10 11: 100 Gm: 150 Gm 1 astronomical unit (au); mean distance between Earth and Sun 10 12: 1 terameter (Tm) 1.3 Tm Optical diameter of Betelgeuse: 1.4 Tm Orbital distance of Saturn from Sun 2 Tm Estimated optical diameter of VY Canis Majoris, one of the largest-known stars: 5.9 Tm Orbital distance of Pluto from ...

  9. Sub-orbital spaceflight - Wikipedia

    en.wikipedia.org/wiki/Sub-orbital_spaceflight

    In this case the lowest required delta-v, to reach 100 km altitude, is about 1.4 km/s. Moving slower, with less free-fall, would require more delta-v. [citation needed] Compare this with orbital spaceflights: a low Earth orbit (LEO), with an altitude of about 300 km, needs a speed around 7.7 km/s, requiring a delta-v of about 9.2 km/s.