Author Topic: Aircraft carriers and spy satellites  (Read 69702 times)

Offline hoku

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Re: Aircraft carriers and spy satellites
« Reply #40 on: 08/02/2021 11:29 pm »
https://www.thedrive.com/the-war-zone/41787/rare-sight-of-two-supercarriers-docked-in-san-diego-with-their-decks-packed-with-aircraft
Nice "satellite messaging" according to one of the commentators to the article.

Any guess on the ground resolution distance? Planet Labs offers "50cm (per pixel?) spatial resolution SkySat imagery". The image might come close to this (3ft/sub-1m?) ...

Offline Blackstar

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Re: Aircraft carriers and spy satellites
« Reply #41 on: 10/28/2021 07:10 pm »
https://www.navalnews.com/naval-news/2021/10/chinas-massive-new-aircraft-carrier-is-as-big-as-it-can-be/


China’s Massive New Aircraft Carrier Is As Big As It Can Be
Aircraft carriers are at the vanguard of China's incredible naval expansion A new, larger super-carrier is being built near Shanghai. Analysis of radar satellite imagery shows that it is as large as China's new bases allow.
H I Sutton 27 Oct 2021

The growth of the Chinese Navy has been incredible. The PLAN (People’s Liberation Army Navy) is barely recognizable from itself twenty years ago. Among the most important developments have been aircraft carriers.

Defense analysts have been trawling open source intelligence (OSINT) to keep up with developments. But like much of China, the shipyard building the latest carrier is protected from traditional satellite observation by impenetrable cloud. A new commercial satellite has provided Naval News with a way to see through this cloud.
« Last Edit: 10/30/2021 01:51 am by Blackstar »

Offline libra

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Re: Aircraft carriers and spy satellites
« Reply #42 on: 11/04/2021 10:11 am »
Bouncing off the Chinese stuff... did they really put 1.7 m mirror spysat in GEO, ground resolution 15 meters, to track down USN ships - under guise of remote sensing ?

https://spacenews.com/china-launches-gaofen-13-observation-satellite-towards-geostationary-orbit/

I wonder if the NRO / CIA / USAF had similar plans at some point in history. 1.7 m is very close from the MOL mirror 72-inch, 1.82 m.

The closest I can think of was that tentative MOL mission with a 100% Navy crew.

Offline LittleBird

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Re: Aircraft carriers and spy satellites
« Reply #43 on: 11/05/2021 10:27 am »
Bouncing off the Chinese stuff... did they really put 1.7 m mirror spysat in GEO, ground resolution 15 meters, to track down USN ships - under guise of remote sensing ?

https://spacenews.com/china-launches-gaofen-13-observation-satellite-towards-geostationary-orbit/

I wonder if the NRO / CIA / USAF had similar plans at some point in history. 1.7 m is very close from the MOL mirror 72-inch, 1.82 m.

The closest I can think of was that tentative MOL mission with a 100% Navy crew.

I guess, re  China, my question would be why would they need to nowadays ?

The US might well have considered it in the 60s, but QUILL had demonstrated LEO radar of similar or better resolution in v early 60s, and PARCAE made passive electronic location of ships operational by late 70s from a "high LEO", so I doubt if it would have stayed a worthwhile mission. [Edit: iirc one of the QUILL declassified docs said Seasat equalled but did not better QUILL's resolution.]

Lifting a KENNEN/Hubble-like payload to GEO would need a Titan Centaur class booster, no ? This would be rather conspicuous before the advent of the Titan 4, and hard to mask.
« Last Edit: 11/05/2021 03:47 pm by LittleBird »

Offline Blackstar

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Re: Aircraft carriers and spy satellites
« Reply #44 on: 11/05/2021 11:32 am »

Online edzieba

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Re: Aircraft carriers and spy satellites
« Reply #45 on: 11/09/2021 09:21 pm »
Not an actual carrier, but a carrier-shaped (and sized! Unlike Iran's infamous mock-up) target in the middle of the desert: https://news.usni.org/2021/11/07/china-builds-missile-targets-shaped-like-u-s-aircraft-carrier-destroyers-in-remote-desert

Offline Blackstar

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Re: Aircraft carriers and spy satellites
« Reply #46 on: 11/09/2021 10:42 pm »
Not an actual carrier, but a carrier-shaped (and sized! Unlike Iran's infamous mock-up) target in the middle of the desert: https://news.usni.org/2021/11/07/china-builds-missile-targets-shaped-like-u-s-aircraft-carrier-destroyers-in-remote-desert

Yes. Some nice satellite images.

« Last Edit: 11/09/2021 10:43 pm by Blackstar »

Offline Blackstar

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Re: Aircraft carriers and spy satellites
« Reply #47 on: 11/10/2021 11:39 pm »

Offline Hobbes-22

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Re: Aircraft carriers and spy satellites
« Reply #48 on: 11/11/2021 09:36 am »
Bouncing off the Chinese stuff... did they really put 1.7 m mirror spysat in GEO, ground resolution 15 meters, to track down USN ships - under guise of remote sensing ?

https://spacenews.com/china-launches-gaofen-13-observation-satellite-towards-geostationary-orbit/

I wonder if the NRO / CIA / USAF had similar plans at some point in history. 1.7 m is very close from the MOL mirror 72-inch, 1.82 m.

The closest I can think of was that tentative MOL mission with a 100% Navy crew.

I guess, re  China, my question would be why would they need to nowadays ?

The US might well have considered it in the 60s, but QUILL had demonstrated LEO radar of similar or better resolution in v early 60s, and PARCAE made passive electronic location of ships operational by late 70s from a "high LEO", so I doubt if it would have stayed a worthwhile mission. [Edit: iirc one of the QUILL declassified docs said Seasat equalled but did not better QUILL's resolution.]



The advantage of GEO is continuous coverage, which you might need for targeting long-range missiles.

Offline Blackstar

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Offline Blackstar

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Re: Aircraft carriers and spy satellites
« Reply #51 on: 11/25/2021 02:09 am »
https://www.csis.org/analysis/signs-point-chinas-third-aircraft-carrier-launching-soon

Signs Point to China's Third Aircraft Carrier Launching Soon
November 9, 2021

Steady progress on the construction of China’s third aircraft carrier has continued throughout 2021, and the vessel—commonly known as the Type 003—may launch in the coming months. Commercial satellite imagery of Jiangnan Shipyard captured on October 23, 2021, reveals that the installation of the carrier’s main external components is nearing completion. Work on other military vessels at Jiangnan appears to have slowed as the shipyard works to fill commercial orders.


Video from a plane flying over the shipyard:

https://streamable.com/p1ds0r


Also this:

https://news.usni.org/2021/11/30/russia-growing-secret-submarine-fleet-key-to-moscows-undersea-future

« Last Edit: 12/02/2021 01:07 am by Blackstar »

Offline LittleBird

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Re: Aircraft carriers and spy satellites
« Reply #52 on: 12/02/2021 02:58 pm »
Bouncing off the Chinese stuff... did they really put 1.7 m mirror spysat in GEO, ground resolution 15 meters, to track down USN ships - under guise of remote sensing ?

https://spacenews.com/china-launches-gaofen-13-observation-satellite-towards-geostationary-orbit/

I wonder if the NRO / CIA / USAF had similar plans at some point in history. 1.7 m is very close from the MOL mirror 72-inch, 1.82 m.

The closest I can think of was that tentative MOL mission with a 100% Navy crew.

I guess, re  China, my question would be why would they need to nowadays ?

The US might well have considered it in the 60s, but QUILL had demonstrated LEO radar of similar or better resolution in v early 60s, and PARCAE made passive electronic location of ships operational by late 70s from a "high LEO", so I doubt if it would have stayed a worthwhile mission. [Edit: iirc one of the QUILL declassified docs said Seasat equalled but did not better QUILL's resolution.]



The advantage of GEO is continuous coverage, which you might need for targeting long-range missiles.

Turns out I was wrong, there's plenty of interest in China in GEO observation of ships, both civil and military, e.g.

https://www.mdpi.com/1424-8220/18/7/2007/htm

and

https://www.mdpi.com/1424-8220/21/22/7547/htm

and references therein, as they say.

Offline LittleBird

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Re: Aircraft carriers and spy satellites
« Reply #53 on: 02/11/2022 05:31 pm »
Bouncing off the Chinese stuff... did they really put 1.7 m mirror spysat in GEO, ground resolution 15 meters, to track down USN ships - under guise of remote sensing ?

https://spacenews.com/china-launches-gaofen-13-observation-satellite-towards-geostationary-orbit/

I wonder if the NRO / CIA / USAF had similar plans at some point in history. 1.7 m is very close from the MOL mirror 72-inch, 1.82 m.

The closest I can think of was that tentative MOL mission with a 100% Navy crew.

I guess, re  China, my question would be why would they need to nowadays ?

The US might well have considered it in the 60s, but QUILL had demonstrated LEO radar of similar or better resolution in v early 60s, and PARCAE made passive electronic location of ships operational by late 70s from a "high LEO", so I doubt if it would have stayed a worthwhile mission. [Edit: iirc one of the QUILL declassified docs said Seasat equalled but did not better QUILL's resolution.]



The advantage of GEO is continuous coverage, which you might need for targeting long-range missiles.

Turns out I was wrong, there's plenty of interest in China in GEO observation of ships, both civil and military, e.g.

https://www.mdpi.com/1424-8220/18/7/2007/htm

and

https://www.mdpi.com/1424-8220/21/22/7547/htm

and references therein, as they say.



I was also at least partly wrong about interest in the US, as  the attached obituary of Bud Wheelon by Jeff Richelson notes the following (I think time period referred to is 1980s but not clear):


Offline libra

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Re: Aircraft carriers and spy satellites
« Reply #54 on: 02/12/2022 06:33 am »
Great ! I was wondering why the average 2 m space or ground mirror couldn't do better than 100 m detail on the lunar surface. So I looked for how the maths work and found the formula is pretty basic.

Formula right here by the great Phil Plait, of "Bad astronomy" fame.
https://www.discovermagazine.com/the-sciences/moon-hoax-why-not-use-telescopes-to-look-at-the-landers

Bottom line
- the ground resolution grows much, much slower than the mirror diameter, which is pretty irritating - but that's the laws of physics and optics, so do with them.  :(

It would take a 10 m+ diameter mirror to get below 100 m details of the lunar surface - so better to send LRO lunar probe instead.

In the case of a MOL 1.82 m diameter mirror
- looking at the Moon from LEO ( = 360 000 km, average) it wouldn't do better than a 150 m resolution
- starring at Earth surface from GEO (= 36 000 km) ground resolution would be 15 meters. Plenty enough for 300 m long ships like aircraft carriers.  Also just enough for very large aircraft like a 747.

Offline LittleBird

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Re: Aircraft carriers and spy satellites
« Reply #55 on: 02/12/2022 02:35 pm »
Great ! I was wondering why the average 2 m space or ground mirror couldn't do better than 100 m detail on the lunar surface. So I looked for how the maths work and found the formula is pretty basic.

Formula right here by the great Phil Plait, of "Bad astronomy" fame.
https://www.discovermagazine.com/the-sciences/moon-hoax-why-not-use-telescopes-to-look-at-the-landers

Bottom line
- the ground resolution grows much, much slower than the mirror diameter, which is pretty irritating - but that's the laws of physics and optics, so do with them.  :(

It would take a 10 m+ diameter mirror to get below 100 m details of the lunar surface - so better to send LRO lunar probe instead.

In the case of a MOL 1.82 m diameter mirror
- looking at the Moon from LEO ( = 360 000 km, average) it wouldn't do better than a 150 m resolution
- starring at Earth surface from GEO (= 36 000 km) ground resolution would be 15 meters. Plenty enough for 300 m long ships like aircraft carriers.  Also just enough for very large aircraft like a 747.

My impression is that we can distinguish three eras.

i) 60s, when idea may well have been loked at by NRO but evidently wasn't pursued, at least in the 1970s, because the roughly KENNEN-sized vehicle used as a hardware baseline in the SEOS study for NASA [see KH-11 thread] needed a Titan Centaur to get it to GEO, and no such launches occurred then. The SEOS study says this vehicle had been proposed [Edit: (to NASA?) by Itek in 1973. The reference is given only as (Itek,1973) and I can't see more detail elsewhere in the report. I did like the reference on page 44 "Petersen, Ralph 1973: Personal communication (report available on 14th floor)"-I'll know where to point my Tardis to ... ]

ii) 80s when Wheelon was on an advisory board and making the suggestion recorded above by Richelson. Richelson clearly knew him well and seems a very reliable source, but we have no reason at all that I know of to assume these suggestions were ever acted on.

iii) Today when a partly declassified JASON study done for NRO has  advocated much larger earthward looking optics at GEO https://irp.fas.org/agency/dod/jason/assembly.pdf (grabs below)

Last is a fascinating report, and suggests that the dreams of Hans Mark are far from dead.
« Last Edit: 02/13/2022 07:16 am by LittleBird »

Offline LittleBird

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Re: Aircraft carriers and spy satellites
« Reply #56 on: 02/14/2022 03:21 pm »
Bouncing off the Chinese stuff... did they really put 1.7 m mirror spysat in GEO, ground resolution 15 meters, to track down USN ships - under guise of remote sensing ?

https://spacenews.com/china-launches-gaofen-13-observation-satellite-towards-geostationary-orbit/

I wonder if the NRO / CIA / USAF had similar plans at some point in history. 1.7 m is very close from the MOL mirror 72-inch, 1.82 m.

The closest I can think of was that tentative MOL mission with a 100% Navy crew.

I guess, re  China, my question would be why would they need to nowadays ?

The US might well have considered it in the 60s, but QUILL had demonstrated LEO radar of similar or better resolution in v early 60s, and PARCAE made passive electronic location of ships operational by late 70s from a "high LEO", so I doubt if it would have stayed a worthwhile mission. [Edit: iirc one of the QUILL declassified docs said Seasat equalled but did not better QUILL's resolution.]



The advantage of GEO is continuous coverage, which you might need for targeting long-range missiles.

Turns out I was wrong, there's plenty of interest in China in GEO observation of ships, both civil and military, e.g.

https://www.mdpi.com/1424-8220/18/7/2007/htm

and

https://www.mdpi.com/1424-8220/21/22/7547/htm

and references therein, as they say.

And one more recent example that caught my eye in an airport lounge online freebie magazine (and no, I can't read Chinese)

https://d.wanfangdata.com.cn/periodical/ChlQZXJpb2RpY2FsQ0hJTmV3UzIwMjExMTMwEg5odHFnYzIwMjEwNTAyMBoIbno1YTQzNW8%253D


Offline libra

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Re: Aircraft carriers and spy satellites
« Reply #57 on: 02/14/2022 03:46 pm »
I have to say that tracking aircraft carriers with GEO sats seems to make some sense. Even if the ground resolution sucks a little (25 ft to 50 ft average, according to the mirror size) US aircraft carriers are more than 1000 ft long, so even from 22 000 miles they should be pretty visible. And since GEO sats can "stare" at the same corner of the Earth for a very long time... including at the Pacific ocean...

Let's suppose an optical spysat, mirror diameter 94-inch, ground resolution 40 ft (= 13 m) - staring at the Pacific Ocean.
It should be able to get pretty decent pictures of a 1100 ft long Jerry Ford supercarrier. Note that it wouldn't be able to spot a 52 ft long F-35C on the deck, or merely as a blurred spot.
https://en.wikipedia.org/wiki/USS_Gerald_R._Ford

Do you think the Chinese have such plan ? or is the idea flawed somewhere ?

Offline LittleBird

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Re: Aircraft carriers and spy satellites
« Reply #58 on: 02/14/2022 03:49 pm »
I have to say that tracking aircraft carriers with GEO sats seems to make some sense. Even if the ground resolution sucks a little (25 ft to 50 ft average, according to the mirror size) US aircraft carriers are more than 1000 ft long, so even from 22 000 miles they should be pretty visible. And since GEO sats can "stare" at the same corner of the Earth for a very long time... including at the Pacific ocean...

Let's suppose an optical spysat, mirror diameter 94-inch, ground resolution 40 ft (= 13 m) - staring at the Pacific Ocean.
It should be able to get pretty decent pictures of a 1100 ft long Jerry Ford supercarrier. Note that it wouldn't be able to spot a 52 ft long F-35C on the deck, or merely as a blurred spot.
https://en.wikipedia.org/wiki/USS_Gerald_R._Ford

Do you think the Chinese have such plan ? or is the idea flawed somewhere ?

You are confusing me with an expert ;-) Somone else might have an opinion ... I don't.

Offline libra

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Re: Aircraft carriers and spy satellites
« Reply #59 on: 02/14/2022 04:13 pm »
I'm certainly not pretending to be an expert either.

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