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0 pointssamplatt1y ago0 comments

With a far point so far away from Earth it also means that it requires only tiny amounts of fuel for major orbit changes.

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justahuman741y ago

My orbital mechanics is (like most people) weak, is this intended as a generalized physical threat to other satellites?

everfrustrated1y ago

Not necessarily.

These types of orbits also have the property that the perceived loiter time is different for the perigee and apogee.

At perigee (closest to Earth) it will be moving very fast and so any changes to velocity will have a large impact (easily change orbit).

While at apogee it will appear to sit in space and move quite slowly. As an example this is used for the Russian GPS system so their satellites can sit in high earth latitudes for longer needing fewer satellites to cover Russia.

inejge1y ago

As an example this is used for the Russian GPS system so their satellites can sit in high earth latitudes for longer needing fewer satellites to cover Russia.

It's used for communications satellites and is called the Molniya orbit[1]. Their GLONASS (positioning system) satellites use circular medium altitude orbits, but with a higher inclination (about 65 deg vs. GPS's 55 deg).

[1] https://en.wikipedia.org/wiki/Molniya_orbit

xattt1y ago

Isn’t GLONASS in geostationary orbit like NAVSTAR/GPS? This would be a fixed orbital distance from Earth.

You may be thinking of highly-elliptical molniya/lightning orbits (1), which enabled state TV broadcasts for high-lat places in Siberia.

(1) https://en.m.wikipedia.org/wiki/Molniya_orbit

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Rebelgecko1y ago

If you can easily adjust your orbit, it's easy to see lots of places on the earth, or tweak what time you will be over a part of the earth (eg if you want to look at something whose owners know to hide it when satellites are overhead)

samplattOP1y ago

Intended? I don't know, you'd have to ask NASA. Does it have that capability? Sure, if it can deploy arbitrary payloads on destination.

kjkjadksj1y ago

It has carried payloads before but little is known about its missions.

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