They have their own frequency allocation they paid big bucks for, and they have 3 satellites) 2 mostly in view at the same time. Different situation entirely.
AMC14 The Rescue mission: Lunar Burn may be a reality.
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They have their own frequency allocation they paid big bucks for, and they have 3 satellites) 2 mostly in view at the same time. Different situation entirely.
XM doesn't offer video. XM Radio is on the Clark belt, but it uses its own 12.5mhz slice of heaven in the 2ghz range (Sirius's is right next door to XM's allocation).
GPS sats are LEO, also in their own frequency allocation.
XM has been testing video for a few years now.
Sirius is now offering video service to consumers.
Sirius is now offering video service to consumers.
XM can test whatever they like. I'm talking about tangible product. 
Either way we're talking a few channels using dedicated bandwidth, quite different from a Satellite TV service where spectrum is reused in different orbital slots.
Either way we're talking a few channels using dedicated bandwidth, quite different from a Satellite TV service where spectrum is reused in different orbital slots.
Actually the Sirius satellites are in a highly elliptical geo-synchronous orbit. They appear from the ground to make a figure 8 pattern between South America at low altitude and Canada at very high altitude. Since our dishes point to a specific point in the sky, Dish satellites must be in a geo-stationary orbit.
Check this out... Its from NASA.
NASA - Science@NASA J-Track 3D
This track's every satellite that's up there now in 3d. If you click on the bird it shows you its path and location. It is possible to have a bird not be on the Clarke belt and still be in the same spot in the sky. The criteria is it has to be traveling the same speed as the earth, and be far enough out that gravity wont pull it in or be too far out that it wont float off into space.
NASA - Science@NASA J-Track 3D
This track's every satellite that's up there now in 3d. If you click on the bird it shows you its path and location. It is possible to have a bird not be on the Clarke belt and still be in the same spot in the sky. The criteria is it has to be traveling the same speed as the earth, and be far enough out that gravity wont pull it in or be too far out that it wont float off into space.
Now, I know someone is eventually going to ask this question, so I will go ahead and ask it. Why doesn't Dish use a antenna system like XM and Sirius.
I believe I know the answer, someone correct me if I am wrong. the fact that frequencies are reused on different sats. and also the DBS signal is lower powered than the high powered Sat. Radio signals.
I believe I know the answer, someone correct me if I am wrong. the fact that frequencies are reused on different sats. and also the DBS signal is lower powered than the high powered Sat. Radio signals.
Basically correct.
The reason why the DBS signal is lower powered is to help facilitate reuse. They have MUCH higher bandwidth needs than the satellite radio companies do. It was hard enough for the sat radio guys to get what they did.
Not it's not, that's why they call it the Clarke belt. The only way to be geo-stationary is to be in a circular geo-synchronous orbit over the equator.
goaliebob99 , don't rush to post - we already see how you 'floating' in planetary mechanics.
Actually, don't go there at all.
Actually, don't go there at all
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The only known location for a satellite to remain in the same location without much rocket thrust is the Clark orbit (Even in the Clark orbit some orbit corrections are required).
However if you give the satellite additional rocket thrust it is possible to have a geostationary satellite not in the Clark orbit (This will require A LOT of fuel, more than what a satellite has).
So theoretically it is possible, practically it is not
However if you give the satellite additional rocket thrust it is possible to have a geostationary satellite not in the Clark orbit (This will require A LOT of fuel, more than what a satellite has).
So theoretically it is possible, practically it is not
Wrong again.
There's no way for it to be far enough out that gravity won't pull it in. Every object exerts a gravitational force on every object, but when the distance between them becomes so great, it becomes negligible.
However, if the Earth had a negligible gravitational force on the satellite, there would be no centripetal force to keep it in orbit.
In addition, it'd have to be so far away to have no significant centripetal acceleration.
Qwert is right...you could theoretically keep an object in the same place in the sky with constant propulsion, but constant propulsion would require an infinite supply of rocket fuel. However, then it wouldn't even be a satellite as it wouldn't be in an orbit.
I'm with goaliebob on everything but his Clark belt comment.
My wag on the potential salvage is that everybody involved has been in this business long enough that every contingency will already be cast in concrete. By that I mean the insurer will go down his list of contingencies, and read out what he must pay in various scenarios including this one. I seriously doubt any insurer would pay a dime to an operator who deliberately deorbited a perfectly functional satellite without even attempting to salvage it's residual value.
As far as the orbital dynamics are concerned, it's all about delta-V and the cost in fuel to give you that delta-V. Just getting off the ground and up to orbital velocity is the big delta-V. Changing altitude or circularizing an orbit doesn't cost that much fuel. However, changing orbital planes to zero degrees inclination does cost. That's why that other rescued satellite went all the way around the moon; to affect a plane change within available fuel. The altitude change alone is obviously not such a big deal if they went all the way "up" to the moon and back.
My wag on the potential salvage is that everybody involved has been in this business long enough that every contingency will already be cast in concrete. By that I mean the insurer will go down his list of contingencies, and read out what he must pay in various scenarios including this one. I seriously doubt any insurer would pay a dime to an operator who deliberately deorbited a perfectly functional satellite without even attempting to salvage it's residual value.
As far as the orbital dynamics are concerned, it's all about delta-V and the cost in fuel to give you that delta-V. Just getting off the ground and up to orbital velocity is the big delta-V. Changing altitude or circularizing an orbit doesn't cost that much fuel. However, changing orbital planes to zero degrees inclination does cost. That's why that other rescued satellite went all the way around the moon; to affect a plane change within available fuel. The altitude change alone is obviously not such a big deal if they went all the way "up" to the moon and back.
Ok lets assume the bird is unharmed, and it is possible to use its on-board engine to move it to the correct location and still get a few years of life out of it.
I say the OP's idea is not all that impossible. I think it depends on if Charlie is willing to take the risk to work out a deal with SES, and whether SES is willing to take the risk on the insurance.
If my understanding of how insurance works is close enough, the insurance to cover the launch is just that, to cover the launch. Since the launch had failed the insurance should cover it. A different insurance (if SES elected to have it) should cover the test/operations of the bird. That insurance may no longer cover the bird anymore due to "pre-existing conditions" clause.
What do you guys think?
I say the OP's idea is not all that impossible. I think it depends on if Charlie is willing to take the risk to work out a deal with SES, and whether SES is willing to take the risk on the insurance.
If my understanding of how insurance works is close enough, the insurance to cover the launch is just that, to cover the launch. Since the launch had failed the insurance should cover it. A different insurance (if SES elected to have it) should cover the test/operations of the bird. That insurance may no longer cover the bird anymore due to "pre-existing conditions" clause.
What do you guys think?
Starting at the same altitude above the surface of a small moon, balls are thrown at different speeds. Regardless of the horizontal speed of the balls, they all fall at the same rate and hit the surface at the same time. The faster balls go further, in the same elapsed time as the slower balls, before hitting the ground. Finally, a ball travels so fast and thus so far before falling, that the ground doesn't appear flat but curves away beneath the ball. At just the correct speed, the ground curves away at the same rate that the ball drops. The ball has achieved orbit.
