Great post. One quick comment on the Geo satellites: while it may be true that three satellites is sufficient to get line of sight coverage to everywhere on earth, in practice it isn’t sufficient.
Beam scan loss on both the satellite payload and terminal side along with field of view geometry (that is a shallow angle of intercept may lead to poor feature definition in imagery) mean that communications and earth observation satellite constellations need to fly birds in orbits that specifically cover the poles to have full earth availability and coverage. This is why you see systems like AEHF, SBIRs high and others fly birds in Molniya (12 hour orbit with 10 hours hang over the pole) or increasingly popular Tundra (24 hour orbit) orbits to provide full coverage over at least the North Pole.
Loved the article! One correction... the Tranche 0 satellites launching later with a partner to test a different orbit are L3Harris birds, not Raytheon ones.
Well there are 3 satellite Geo constellations, they just provide lousy service about 60 deg. In fact some providers have many satellites in Geo because their payloads have narrow FOV or they want more capacity.
Actually you’ll sometimes see 4 satellite GEO constellations with one held close as a spare in a particularly high throughput orbit in case the main money maker fails or it’s long in the tooth and they anticipate retiring it soon.
But I'm going to rain on the parade a little bit. Not because what you're saying is untrue, but because everything the SDA is buying still keeps the USSF in a support role. There's no protection of space assets there. And that's always been the case (no pun intended). Most of the missions you're seeing with the new stuff still falls in the realm of remote sensing, communications, etc., which are missions that the USAF and other have done for a while.
At the same time, at least the SDA is helping the USSF update its current mission sets, and that's exciting! Maybe that allows it some expansion once those new systems are in place? Although, the USSF needs policy changes to expand from support as well.
When I read "the speed that LEO satellites travel (10km/sec) make individual satellites more difficult targets vs stationary GEO satellites," and this is often cited elsewhere too, I wonder what is doing the targeting. Lasers to blind? Lasers to incapacitate? Lasers on the ground? Lasers in space? EM weapons? Objects in space (which would soon make LEO a full of debris days into a conflict?) Active objects blocking field of view (for managing escalation)? Naturally, did seeing someone readying or ready to disrupt GEO sats finally make the SDA plan take off? This implies a window we are trying to close.
Great post. One quick comment on the Geo satellites: while it may be true that three satellites is sufficient to get line of sight coverage to everywhere on earth, in practice it isn’t sufficient.
Beam scan loss on both the satellite payload and terminal side along with field of view geometry (that is a shallow angle of intercept may lead to poor feature definition in imagery) mean that communications and earth observation satellite constellations need to fly birds in orbits that specifically cover the poles to have full earth availability and coverage. This is why you see systems like AEHF, SBIRs high and others fly birds in Molniya (12 hour orbit with 10 hours hang over the pole) or increasingly popular Tundra (24 hour orbit) orbits to provide full coverage over at least the North Pole.
That launch chart for 2023 has a bigger wedge for the U.S.
2024 will be even more lopsided.
And if you adjusted the graph to instead count launches by mass? Oh boy...
Loved the article! One correction... the Tranche 0 satellites launching later with a partner to test a different orbit are L3Harris birds, not Raytheon ones.
Well there are 3 satellite Geo constellations, they just provide lousy service about 60 deg. In fact some providers have many satellites in Geo because their payloads have narrow FOV or they want more capacity.
Actually you’ll sometimes see 4 satellite GEO constellations with one held close as a spare in a particularly high throughput orbit in case the main money maker fails or it’s long in the tooth and they anticipate retiring it soon.
Hey Case!
First--this is good stuff.
But I'm going to rain on the parade a little bit. Not because what you're saying is untrue, but because everything the SDA is buying still keeps the USSF in a support role. There's no protection of space assets there. And that's always been the case (no pun intended). Most of the missions you're seeing with the new stuff still falls in the realm of remote sensing, communications, etc., which are missions that the USAF and other have done for a while.
At the same time, at least the SDA is helping the USSF update its current mission sets, and that's exciting! Maybe that allows it some expansion once those new systems are in place? Although, the USSF needs policy changes to expand from support as well.
When I read "the speed that LEO satellites travel (10km/sec) make individual satellites more difficult targets vs stationary GEO satellites," and this is often cited elsewhere too, I wonder what is doing the targeting. Lasers to blind? Lasers to incapacitate? Lasers on the ground? Lasers in space? EM weapons? Objects in space (which would soon make LEO a full of debris days into a conflict?) Active objects blocking field of view (for managing escalation)? Naturally, did seeing someone readying or ready to disrupt GEO sats finally make the SDA plan take off? This implies a window we are trying to close.