You have to be visual range, or radar range of you have one, which is the horizon plus a bit more depending how high above sea level your are and how tall your target is.
If you’re on a ship, unless you’re using an advanced radar that bounces signals against the ionosphere your radar horizon is surprisingly short, something around 12 nautical miles give or take. And the sea is big and Iran is quite far.
This is one big reason why aircraft are used for surveillance at sea. They can go much higher than any ship’s radar antenna mast every could be which significantly increases their detection and identification ranges. They can also travel out to see when further.
Right now because if this, Iran now has the intel that the French carrier is approaching without even having to send an aircraft out to look for it. If they even ever have the ability to at this point.
Sort of. Satellite resources are surprisingly scarce, so a lot are focused where people are, i.e. land. Plus, for the imagery sats that are focused on the ocean, ships are also tiny in a literal ocean of blue. It’s just a spec. While the resolution could be good, have fun looking for that spec. That’s why most countries use signal collection to locate vessels at sea. (I’m over-simplifying a lot, but you get the picture)
There are a surprising amount of false positives when using object detection on maritime imagery. While a carrier is a spec, there are a ton of specs in the ocean that can look similar enough. Plus, weather has a huge hand to play. If it were always perfectly clear, then it’s an easier problem, but one cloud can really mess up the detection. Ultimately, ship detection is a difficult problem (not intractable but still hard).
False positives are fine, you assign 1, 10, 50, 100 analysts to review hits. You only need to find it once, then the search area becomes incredibly small for each subsequent satellite pass.
I’m not saying that it is easy, just that you don’t need to have a surface ship within 15 nm in order to see it.
‘Take a picture of the entire ocean and look for ships’ is simple, but executing that plan is not.
It requires hundreds of millions of dollars of reconnaissance satellites, and an entire branch of personnel to operate and digest the information.
This is why the US operates carrier battle groups instead of just sailing their carriers everywhere with a small escort. They can’t hide, but they can pack enough offensive and defensive power into a tiny area to make most attacks infeasible.
Anyways, there’s a reason submarines exist
True, and even they’re vulnerable when they surface (if they’re moving), the v-shaped wake is also very detectable from space where satellites can detect wave heights within 3cm. It’s not easy for humans to find, but with billions of dollars to spend on computers, these kinds of things are very much within the reach of sovereign nations.
The Swedish Navy’s ships do have some bonkers designs, like massive barcodes printed on the side. It’s so that when they get back to port they can scan the navy in.
You have to be visual range, or radar range of you have one, which is the horizon plus a bit more depending how high above sea level your are and how tall your target is.
If you’re on a ship, unless you’re using an advanced radar that bounces signals against the ionosphere your radar horizon is surprisingly short, something around 12 nautical miles give or take. And the sea is big and Iran is quite far.
This is one big reason why aircraft are used for surveillance at sea. They can go much higher than any ship’s radar antenna mast every could be which significantly increases their detection and identification ranges. They can also travel out to see when further.
Right now because if this, Iran now has the intel that the French carrier is approaching without even having to send an aircraft out to look for it. If they even ever have the ability to at this point.
So satellites can see my truck’s plate but an aircraft carrier and it’s escrow fleet are too… Small?
Sort of. Satellite resources are surprisingly scarce, so a lot are focused where people are, i.e. land. Plus, for the imagery sats that are focused on the ocean, ships are also tiny in a literal ocean of blue. It’s just a spec. While the resolution could be good, have fun looking for that spec. That’s why most countries use signal collection to locate vessels at sea. (I’m over-simplifying a lot, but you get the picture)
Seems like an simple but tedious job. Something that a computer can do.
Object detection algorithms are incredibly fast and can learn to tell the difference between an aircraft carrier and an ocean.
There are a surprising amount of false positives when using object detection on maritime imagery. While a carrier is a spec, there are a ton of specs in the ocean that can look similar enough. Plus, weather has a huge hand to play. If it were always perfectly clear, then it’s an easier problem, but one cloud can really mess up the detection. Ultimately, ship detection is a difficult problem (not intractable but still hard).
False positives are fine, you assign 1, 10, 50, 100 analysts to review hits. You only need to find it once, then the search area becomes incredibly small for each subsequent satellite pass.
I’m not saying that it is easy, just that you don’t need to have a surface ship within 15 nm in order to see it.
It kind of sounds like you’re saying that. Anyways, there’s a reason submarines exist
It is simple, it is not easy.
‘Take a picture of the entire ocean and look for ships’ is simple, but executing that plan is not.
It requires hundreds of millions of dollars of reconnaissance satellites, and an entire branch of personnel to operate and digest the information.
This is why the US operates carrier battle groups instead of just sailing their carriers everywhere with a small escort. They can’t hide, but they can pack enough offensive and defensive power into a tiny area to make most attacks infeasible.
True, and even they’re vulnerable when they surface (if they’re moving), the v-shaped wake is also very detectable from space where satellites can detect wave heights within 3cm. It’s not easy for humans to find, but with billions of dollars to spend on computers, these kinds of things are very much within the reach of sovereign nations.
It depends a great deal on if you have access to a real-time satellite feed and know where to look.
It’s the ocean. The majority of Earths surface where there’s usually not much going on
why don’t ships at sea simply disguise themselves as a rock or shrubbery?
Or as a duck if they need to move.
BTW sweden have some cool ship disguises.
The Swedish Navy’s ships do have some bonkers designs, like massive barcodes printed on the side. It’s so that when they get back to port they can scan the navy in.
I just searched for some more info on this and was definitely surprised by the design. That’s pretty neat. 😆
(‘scandinavian’ for people like me)
Good idea, you should sketch it up in paint and post it to NCD
China and Russia could also just tell Iran, if they don’t have satellites of their own
It wasn’t exactly a secret, France publicly announced it was going to move to the eastern med