No that is not true I disagree
a snap shot of one place and time does not equate to 24/7 365 surveillance
if you want to track a carrier using satellites you need a whole constellation of them dedicated to just one thing, tracking carriers and thats just practical
if what you said was true no one would building carriers
Why would China need 24/7 365 satellite surveillance?
The key limitation/difficulties of using satellites for targeting are:
1) field of view vs resolution - the smaller the field of view, the better the resolution. But searching a large body of water with a small search box equals low probability of successful detection.
2) your kill chain vs time on target. Satellites typically only have LoS for a few minutes, which is not enough time to mount a conventional strike package.
However, there are very China-specific factors that make both those difficulties significantly less challenging.
First of all, China’s goal is not to scour the world’s oceans hunting USN carriers. In the event of open conflict, they just need to keep USN carriers a certain distance from the mainland so they cannot mount effective strikes against Chinese targets.
That dramatically reduces the body of water Chinese satellites need to look in.
What more, that body of water is very close to the mainland, and so would allow them to bring all sorts of other detection assets into play, like OTH radars; AWACS, drones and the like. So China could use additional sensors to help them direct their recon satellites to look at areas of interest instead of just systematic scanning.
In addition, if China and the US ever actual come to blows, all existing rules go out the window.
China could simply declare all the waters within the first and second island chains as open conflict zones, but set up safe passage highways for all civilian and neutral shipping to use (which would be easily and heavily monitored by Chinese coast guard ships).
Anything sailing outside of those safe zones will be assumed as hostile to China, and engaged without further warning.
That will effectively clear the board, (especially if China sinks a few ships to show they are not messing around) and pretty much eliminate all civilian and neutral maritime traffic from the defined conflict zones.
What that does is allow Chinese satellites to use the maximum possible search boxes to scan to waters for anything big enough to be a Burke or carrier, and reduce the number of hits to a small enough size to allow Chinese satellites to automatically take snapshots of any hits at higher resolution without disrupting their normal search pattern.
The coding for such a task is pretty elementary stuff, and I am just using an extreme example to illusate just how easy China can make things for themselves.
With the advances China has been making in complex image recognition software, as is evidenced with its proliferating use (Chinese hotels even use facial recognition these days, and have been for years). They can easily add in automated checks to weed out non-warships.
All of this will reduce the number of hits to a small enough number that a few human analysts could check all of them in real time.
As soon as a carrier is detected, the race is on to get to the end of the kill chain before they loose LoS with the satellite.
Again, China has the unique advantage of AShBMs, which can reduce the missile flight time to mere minutes. With real time image processing and human verification; and Chinese rocket forces on a hair trigger just waiting for coordinates, the entire kill chain could be compressed to be only a minute or two longer than the flight time of an AShBM fairly easily.
They can compress that further to be mere seconds after detection if their software is up to scratch to provide high probability matches automatically. In which case human independent verification can be cut-out and the computer can upload target coordinates to launch vehicles directly.
But they should not need to take that risk, since they have the option of going into added time with satellites if needed.
If a Chinese satellite has indeed detected an enemy carrier battlegroup within AShBM range of the mainland, China would gladly sacrifice that satellite, and several more besides if that is what is needed.
As such, Chinese recon satellites can and will use up their entire service lives’ fuel supply if needed to remain on station longer and/or get on station quicker to provide continuous imaging support for as long as possible the AShBM could reasonably need to complete its kill chain.