| > There are 510 trillion square miles of surface area on the planet. I understand it's a big job, but that's why big governments have billion dollar budgets and toys.
Also remember we have no need to take photos of the entire surface, only the Atlantic (and even then, only the North Atlantic right now) >You could, conceivably, completely miss the object in your imaging passes I feel quite confident when images are taken their exact co-ordinates are known, so it can be quickly determined if you've "missed" a patch or if you have them all. >* or the satellite you have tasked for a particular ground track has an error in it's imaging sensor or downlink equipment* I feel quite certain they've tested these things extensively, and they're not going find some previously unknown bug while looking for a ship in the ocean. They work properly. > * You might also have to move the satellites around occasionally making imaging useless during these periods as well.* I thought most satellites were in orbits that make it possible to image almost the entire surface without moving them. > Also.. there's night and weather I didn't say it was going to be easy. > whole-earth real-time imaging is seriously difficult I'm not for one second proposing whole-earth real-time imaging. |
Yes.. but spending a billion dollars to save a few million is kind of silly, isn't it?
> feel quite confident when images are taken their exact co-ordinates are known, so it can be quickly determined if you've "missed" a patch or if you have them all.
Knowing you're missing data is one thing, but if you're _looking_ for a _moving_ object it can really set you back. You also then have to wait for that satellite, or another one on the same ground track to make the next pass. Most earth imaging satellites have a 90 minute orbital period. Even then, the earth is spinning, so you can't get back to the _exact_ spot very easily (if at all). Still confident this is easy?
> I feel quite certain they've tested these things extensively, and they're not going find some previously unknown bug while looking for a ship in the ocean. They work properly.
You can't image from geosynchronous orbit. I mean, you can, but it's pointless. You need a polar orbit. These orbits aren't stable. You need to adjust them (seriously, sign up for the GPS update list and see how often they have to be adjusted and moved).
Also, "they work properly." Clearly you're not an engineer. Things work properly until they don't. Which could be because of component failure, debris strike or you know, plain ole solar flares. These objects are in _space_. It sort of ups the bar.
> thought most satellites were in orbits that make it possible to image almost the entire surface without moving them.
As I said before, these orbits aren't perfectly stable. You need to boost and adjust and make movements. You may also want to put a new satellite in a slot where a previous satellite (with lessor technology) was. This all requires an insane amount of coordination and effort. Or, an insanely huge cluster.
> I didn't say it was going to be easy.
You made it sound as if it was a foregone conclusion. My effort was to point out that it is in no way that simple. It's going to be hard, it's going to cost a lot, you're going to have to throw people and money and equipment at it _constantly_. Is this justifiable for looking for missing objects? Probably not.
> I'm not for one second proposing whole-earth real-time imaging.
Then good luck finding those _moving_ objects. Also, I'd like to know what orbit takes a satellite only over the Atlantic Ocean. Yes, there are orbits that can "park" over an area, but those orbits are useless for the type of imaging you're suggesting, so you have to deal with the whole-earth problem anyways.