Editing Communications satellite (section)

=== Medium Earth orbit (MEO) ===
{{Main|Medium Earth orbit}}

A medium Earth orbit is a satellite in orbit somewhere between {{convert|2,000|and|35786|km|mi}} above the Earth's surface.  MEO satellites are similar to LEO satellites in functionality. MEO satellites are visible for much longer periods of time than LEO satellites, usually between 2 and 8 hours. MEO satellites have a larger coverage area than LEO satellites. A MEO satellite's longer duration of visibility and wider footprint means fewer satellites are needed in a MEO network than a LEO network. One disadvantage is that a MEO satellite's distance gives it a longer time delay and weaker signal than a LEO satellite, although these limitations are not as severe as those of a GEO satellite.

Like LEOs, these satellites do not maintain a stationary distance from the Earth.  This is in contrast to the geostationary orbit, where satellites are always {{convert|35786|km|mi}} from Earth.

Typically the orbit of a medium Earth orbit satellite is about {{convert|10,000|mi|km|order=flip}} above Earth.<ref>{{cite book |last1=Pelton |first1=Joseph N. |title=The Basics of Satellite Communications |date=2006 |publisher=Intl. Engineering Consortiu |isbn=978-1-931695-48-0 |url=https://www.google/books/edition/The_Basics_of_Satellite_Communications/ClpAJ6fLj6gC?hl=en&gbpv=0 |language=en}}</ref> In various patterns, these satellites make the trip around Earth in anywhere from 2 to 8 hours.

==== Examples of MEO ====
* In 1962, the communications satellite, '''Telstar''', was launched. It was a medium Earth orbit satellite designed to help facilitate high-speed telephone signals. Although it was the first practical way to transmit signals over the horizon, its major drawback was soon realised. Because its orbital period of about 2.5 hours did not match the Earth's rotational period of 24 hours, continuous coverage was impossible. It was apparent that multiple MEOs needed to be used in order to provide continuous coverage.
* In 2013, the first four of a constellation of 20 MEO satellites was launched. The [[O3b]] satellites provide [[Internet access|broadband internet services]], in particular to remote locations and maritime and in-flight use, and orbit at an altitude of {{convert|8063|km|mi|0}}).<ref>{{cite web|url=https://www.arianespace.com/wp-content/uploads/2015/10/VS05-O3b-launchkit-EN.pdf|title=Soyuz Flight VS05 Launch Kit|website=Arianespace|date=June 1, 2013|access-date=27 August 2020}}</ref>