MadSci Network: Engineering

Re: satelites monitoring our daily activities

Date: Tue Oct 5 10:55:14 1999
Posted By: Adrian Popa, Directors Office, Hughes Research Laboratories
Area of science: Engineering
ID: 938627552.Eg


Fiction writers often use factual information about specific real systems 
and then combine this information to form "science fiction" systems with 
capabilities that are far beyond what current technology can do. In some 
cases these extensions are plausible in other cases they might violate the 
laws of physics, as we currently understand them. This makes very 
interesting books and motion pictures but often it confuses the public about 
what is real and what is fiction. Your questions contain both forms of 
science fiction. I particularly like the books by Tom Clancy such as Patriot 
Games in which similar satellite surveillance technology is used to find 
terrorists; however, even Clancy tends to stay just a little ahead of real 
technology so that his stories could happen in the future. Unfortunately, 
Hollywood often stretches the books concepts even farther into the future so 
that they are less believable if not totally false.

In the United States, there are 13 major members of the intelligence 
community, headed by the Director of Central Intelligence (DCI), 
Mr.George Tenet (who also leads the Central Intelligence Agency (CIA) - one 
of the 13 members of the Community). You can read about the mission of these 
13 agencies on the DCI web site at:

Three key sources of intelligence are SIGINT, IMINT and HUMINT.

SIGINT  Signals intelligence is used to monitor electromagnetic energy 
(e.g. telephone, telegraph, radio, radar, satellite communications, 
microwave links, air traffic control, cell phones etc.)

The National Security Agency (NSA) is a key player in the SIGINT mission. 

"The SIGINT mission allows for an effective, unified organization and 
control of all the foreign signals collection and processing activities of 
the United States." 

IMINT  Image intelligence is used to collect images with cameras and radar 
type devices.

The National Reconnaissance Office (NRO) is the single, national program to 
collect the US governments IMINT needs through spaceborne reconnaissance. 
HUMINT  Human intelligence is acquired by people on the ground (e.g. spies, 
monitors, bugging, hacking, diplomats etc.)

HUMINT is conducted internationally by the Central Intelligence Agency (CIA) 
and within the United States by the Federal Bureau of Investigation (FBI).

IMINT collects images using aircraft (e.g. U2, TR-2) and spacecraft (e.g. 
KH-11 etc.). The weather, haze and smoke, and atmospheric turbulence and the 
size of the camera lenses or radar antennas set the limit of resolution (the 
detail) in the images taken. Aircraft can take pictures with resolution less 
than an inch from many miles away and automobile license plates and, under 
the best of conditions, human images can be obtained. Good satellite imagery 
has resolution of about a meter (3 feet) and can images houses, ships, 
aircraft but cannot resolve people or small vehicles. A 2-meter (6 ft) tall 
person would consist of 2 dots (pixels) in a picture with 1-meter 
resolution. Also, motion pictures can be taken so that 3D views can be 
generated of objects flown over by aircraft and in some cases spacecraft.

Satellites have to look through the whole atmosphere from hundreds of km 
(miles) in space making detailed images very difficult. Most fiction books 
and movies greatly exaggerate the resolution of pictures taken from space. 
About 15 years ago, secret pictures taken by a satellite of a Russian aircraft 
carrier under construction were leaked to the press and they are the 
most detailed pictures from space ever released. Several magazines published 
the pictures at that time. However, the detail of the pictures was not good 
enough to see people. The book "Deep Black : Space Espionage and National 
Security" by William E. Burrows  / Published 1987 (Publisher Out Of Stock) 
has these photographs. Perhaps you can find it in your library. These 
computer-processed pictures are truly amazing. 

Cameras cannot see through most materials and most countries know when spy 
satellites are passing overhead so that they keep secret airplanes etc. 
under cover during these times. Infrared cameras can sense heat patterns 
such as cool shadows even after some objects has been moved and some 
information can be obtained from these rapidly fading heat images. It is 
extremely difficult to take pictures of moving objects or to find objects to 
photograph during a satellite flyover. The pictures are still picture frames 
and each frame must be computer processed to remove as much of the 
atmospheric blurring as possible. Imagine the difficulty of flying over a 
city in about 5 minutes and trying to find one person in a million, 
somewhere on the ground, who happened to be out-of-doors, in view of the 
spacecraft, clear of buildings and without clouds, smog or fog in the way.

Imaging radar can see through clouds, weather and nonmetallic materials. The 
resolution of radar imagery is about 30 cm (1 ft) from aircraft and 10 
meters (30 ft) from spacecraft. Even at this resolution, much intelligence 
information can be obtained - including roads, bridges, dams, airfields, and 
numbers and types of aircraft and missiles, buildings etc. Spaceborne radar 
imagery taken from the space shuttle can be found on the NASA/JPL web site 

In a fictional story, the writer can combine the resolution of a camera in 
an aircraft with a camera in a space craft and the penetration capabilities 
of radar and come up with the "Enemy of the State" type movie. However, even 
with this sci-fi equipment, one would have to have the ability to quickly 
find one person in a million, who happens to be in an observable location 
and not moving very quickly and you see the magnitude of the IMINT problem.

SIGINT is a more interesting technique because radio waves and microwaves 
can pass through most materials except for metals and deep seawater. Thus 
all types of wireless communications including telephones and cell phones 
can be monitored from the ground, from the air, and from space. The problem 
with SIGINT is the huge number of channels that must be monitored at the 
same time all over the world. Millions of telephone calls, hundreds of 
thousands of radio channels, radar sets, microwave channels, air traffic 
control signals, police and fire radios etc. Determining which channels have 
good intelligence information and which are just kids talking is a huge 
problem. Who can possibly listen to millions the calls? For that, you would need 
millions of listeners. 

The NSA monitors all of these signals, all over the world, all of the time  
and records them. No one can possible sort through this huge amount of data 
unless a time, location and hopefully a channel frequency can be zeroed in 
on. This is why it can take many hours or days to recover the communications 
such as those between the Russian fighter pilots when they shot down the 
Korean Boeing 747 as it strayed off course over the Soviet Union about 10 
years ago. The general location was known, the general time was known and 
the frequencies of aircraft communications channels where known, yet it 
still required hours of searching through the recordings from many different 
SIGINT locations to find out what happened. However, when they did recover 
the communications between the fighter pilots they had a very graphic sound 
picture of the killing of about 250 people!

More recently the news people, private detectives (and others) have figured 
out how to use SIGINT and have eavesdropped on the cell phone and wireless 
remote telephone conversations of many famous and ordinary people. By 
placing a radio bug on a person or a vehicle it is often possible to find 
the location of people perhaps to take pictures. This can be used for bad 
purposes or for good purposes such as tracking down stolen automobiles.

Perhaps one of the most interesting SIGINT leaks was discussed in the 
nonfiction book "Spy Catcher" by Peter Wright in which spies eavesdropped on 
computer terminals in foreign embassies by listening to the electronic noise  
signals that most computers and FAX machines radiate. This is part of the 
HUMINT mission which uses people on the ground to collect information. This 
is the most difficult and sometimes the most useful or sometimes the  
most unreliable source of information.

Today in the real world we are being monitored by ultra miniature video 
cameras, voice and TV wireless transmitters, wire tapping and cell phone 
monitoring, wireless telephone listening, computer hacking and eavesdropping 
of all sorts is being used to invade our privacy. These are much more 
threatening to our freedom than remote sensing from aircraft or space will 
ever become.

Best regards, Your Mad Scientist
Adrian Popa

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