Re:Chinese city to launch man-made moon to light up skies
by QuotedForTruth on Thursday October 18, 2018 @11:02AM
(#18248862)
They can have inclination other than 0. If inclination is 0 thats a "geostationary" orbit, a special case of geosynchronous. In fact these are not stable and degrade into mere geosynchronous orbits without station keeping. In general though geostationary orbits are more useful since they are fixed competely in the sky. Ground antenna dont have to track the satellite as it moves north/south in the sky.
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Re:Chinese city to launch man-made moon to light up skies
by M_Bakhtiari on Friday October 19, 2018 @02:49AM
(#18254662)
In this case a pair of satellites in a Tundra orbit [1] inclined to spend most of its time over this particular city seems like the right orbit for the job (as silly as it is to light a city by satellite), which is why I was curious to get an explanation behind the sweeping statement that geosynchronous (not geostationary in particular) orbits had to be in a line along the equator.
Re:Chinese city to launch man-made moon to light up skies
by QuotedForTruth on Friday October 19, 2018 @09:44AM
(#18256645)
Oh thats interesting. I hadn't heard of Tundra orbits. Wiki says 2 can provide continous coverage over an area. Wouldnt 1 be enough to act as a moon then? You only need it for half of the day and their period is 1 day right?
Re:Chinese city to launch man-made moon to light up skies
by M_Bakhtiari on Monday October 22, 2018 @03:17AM
(#18272773)
The problem with using just one is that geosynchronous orbital periods are one sidereal [1] day, not one solar day. So depending on the time of the year, the satellite would be in position in the wrong half of the day. On the other hand a satellite in Tundra orbit spends not half but more than half of its time in the designated area. Maybe a good compromise orbit could be found.