Chapter No. 10: Space Missions,
What are the differences between high earth orbits and low earth orbits?
High earth orbits
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Low earth orbits
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Height from the earth's surface for these orbits is greater than or equal to 35780 km.
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Height from the earth's surface for these orbits is between 180 km and 2000 km.
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Satellites revolving in these orbits take around 24 hours to complete one revolution around the earth.
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Satellites revolving in these orbits take around 90 minutes to complete one revolution around the earth.
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The satellites appear stationary with respect to earth.
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The satellites do not appear stationary with respect to earth.
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Critical velocity of satellites revolving in these orbits is higher than that of satellites revolving in low earth orbits.
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Critical velocity of satellites revolving in these orbits is lower than that of satellites revolving in high earth orbits.
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Example: Geostationary satellites revolving parallel to equator of the earth revolve in these orbits.
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Example: International space station and Hubble telescope revolve in these orbits.
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