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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

    Transatmospheric orbit (TAO): geocentric orbits with an apogee above 100 km and perigee that intersects with the defined atmosphere. [4] Very low Earth orbit (VLEO) is defined as altitudes between approximately 100 - 450 km above Earth’s surface. [5] [6] Low Earth orbit (LEO): geocentric orbits with altitudes below 2,000 km (1,200 mi). [7]

  4. Thermosphere - Wikipedia

    en.wikipedia.org/wiki/Thermosphere

    The first term in (3) on the right is the global mean of the exospheric temperature (of the order of 1000 K). The second term [with P 2 0 = 0.5(3 sin 2 (φ)−1)] represents the heat surplus at lower latitudes and a corresponding heat deficit at higher latitudes (Fig. 2a). A thermal wind system develops with the wind toward the poles in the ...

  5. 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.

  6. Scale height - Wikipedia

    en.wikipedia.org/wiki/Scale_height

    These figures should be compared with the temperature and density of Earth's atmosphere plotted at NRLMSISE-00, which shows the air density dropping from 1200 g/m 3 at sea level to 0.125 g/m 3 at 70 km, a factor of 9600, indicating an average scale height of 70 / ln(9600) = 7.64 km, consistent with the indicated average air temperature over ...

  7. Line-of-sight propagation - Wikipedia

    en.wikipedia.org/wiki/Line-of-sight_propagation

    Usually, a factor k is used in the equation above, modified to be k > 1 means geometrically reduced bulge and a longer service range. On the other hand, k < 1 means a shorter service range. Under normal weather conditions, k is usually chosen [5] to be 43. That means that the maximum service range increases by 15%.

  8. Bill Anders, Apollo 8 astronaut who took iconic 'Earthrise ...

    www.aol.com/news/bill-anders-apollo-8-astronaut...

    Astronaut Bill Anders, who orbited the moon aboard Apollo 8 in 1968, has died in a plane crash off the coast of Washington state. His photo 'Earthrise' captivated the world.

  9. MW 18014 - Wikipedia

    en.wikipedia.org/wiki/MW_18014

    MW 18014 was a German A-4 test rocket [nb 1] launched on 20 June 1944, [1] [2] [3] at the Peenemünde Army Research Center in Peenemünde.It was the first human-made object to reach outer space, attaining an apogee of 176 kilometres (109 mi), well above the Kármán line that was established later as the lowest altitude of space. [4]