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    Published 27 March 2013 Referencing Hub media
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    A low-Earth orbit1 (LEO) is usually a circular orbit with an altitude2 from 200–2,000 km.

    Advantages: requires less energy to put a satellite3 into LEO, less power4 needed to transmit data5, high-resolution images

    Period: about 90 minutes

    Satellite examples: International Space Station

    Landsat 7, CryoSat-2, COSMIC/FORMOSAT-3

    Transcript

    Dr Allan McInnes

    What is a low-Earth orbit? An orbit that’s low near the Earth, so we usually think of a low-Earth orbit as starting around about 200 kilometres in altitude and extending up to about 2,000 kilometres.

    What speed do things move at in low-Earth orbit? It varies depending on how high you are. That’s the thing with orbits – the lower you are, the faster you tend to be going but fast enough that you’ll circle the Earth once every 90 minutes or so.

    We use low-Earth orbiting satellites for a wide range of things. A lot of science missions tend to be down in those kind of orbits. Low-Earth orbits have the advantage that you get to see a lot of the Earth, but you get to see it up close. So you’re circling the Earth, you only see a small piece at a time but you are very close to it. That’s great for science – you can get a lot of detail.

    1. orbit: The path of an object as it revolves around another object. For example, the path the Moon takes as it moves around the Earth is its orbit.
    2. altitude: 1. The height of something, usually height above sea level. 2. In astronomy, the angular distance of a natural or artificial satellite above the horizon.
    3. satellite: Any object that orbits around another object.
    4. power: 1. The rate at which work is done (defined as work divided by time taken). 2. Mechanical or physical energy, force or momentum.
    5. data: The unprocessed information we analyse to gain knowledge.
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      orbit

    1. + Create new collection
    2. The path of an object as it revolves around another object. For example, the path the Moon takes as it moves around the Earth is its orbit.

      power

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    4. 1. The rate at which work is done (defined as work divided by time taken).

      2. Mechanical or physical energy, force or momentum.

      altitude

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    6. 1. The height of something, usually height above sea level. 2. In astronomy, the angular distance of a natural or artificial satellite above the horizon.

      data

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    8. The unprocessed information we analyse to gain knowledge.

      satellite

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    10. Any object that orbits around another object.