Military Reconnaissance Satellites (IMINT)

When detailed reports of geographical areas, military installations and activities, troop positions, or other picture-based intelligence are required, policy-makers and analysts turn to data provided by IMINT (Image Intelligence) satellites.  Operating in low, near-polar orbits at an altitude of between 500 and 3,000 kilometers, and maintaining the same orbit around the Earth, they make about 14 revolutions per day.  IMINT satellites use either photo-optic, electro-optic infrared, or radar technology to scan a new swath of ground with each orbit. 

VARIETIES OF IMINT SATELLITES

Photo-optic.  An image is recorded on film, after which it is retrieved, processed, and analyzed.  A one to three day time lag from the time the data is requested and the time the image can be used makes photo-optic satellites more useful for strategic planning than for tactical combat situations.  They cannot penetrate clouds or darkness and can be fooled by camouflage. 

EO-IR—Electro-optical/Infra-red.  These satellites provide full-spectrum photographic imagery, including infra-red.  Digital enhancement provides the opportunity to further sharpen and define images produced by these satellites.  IR sensors can spot heat sources at night but cannot spot vehicles or aircraft on the ground once their engines are cold.  They are also unable to penetrate clouds and darkness and are only slightly less likely to be fooled by camouflage.  IR sensors can also be fooled by dummy heat sources and can be blocked to some degree by special IR-netting.

Radar Imaging.  An image is created by high-energy radar pulses reflected off the Earth’s surface.  Several types of radar emissions are produced, some of which are combined on the same satellite.  Using Synthetic Aperture Radar technology, now a mature technique used to generate radar images in fine detail, illumination is generated in the form of radar pulses, allowing imaging at any time of day or night.  Long wavelengths allow penetration of cloud cover and imagery even in dusty conditions.  Doppler-radar technology is used to spot movement of ships and aircraft, and GMTI radar is useful for detecting ground movement of vehicles.  RORSAT-type satellites are primarily used over oceanic regions to search for shipping.  Resolution is not as good as photo-optic or E-O satellites, however, and analyzing its imagery requires a higher level of skill.  Images can also be subject to "noise" due to “backscatter” (a form electronic static) caused by certain unfavorable conditions such as rough seas or nearby large, metallic surfaces.  Radar satellites are also susceptible to active jamming.

AMERICAN SATELLITE CAPABILITIES

The United States reportedly maintains at least six newer reconnaissance satellites that have been placed in orbit during a series of launches throughout the last decade, including: 

Key Hole (KH) Satellites

Key Hole-class satellites return images to Earth via an electronic link.  The most advanced of these satellites has a resolution of around 10-15 centimeters, but cannot see through clouds, nor do they have “dwell capability” (the ability to maintain orbit over a specific location).  Key Hole satellites closely resemble the Hubble Space Telescope, yet their optical and infrared sensors are much different.  A series of satellites that costs around $1.5 billion, Key Hole enables identification of objects 6 to 8.5 inches across, although it is speculated that the actual resolution may even be as good as 4 inches.  At least three versions of the KH-11 and KH-12, the most advanced in the Key Hole series, have been launched since 1992.

KH-11 satellites have a higher orbit than their predecessors—operating with perigees (the point in the orbit closest to the Earth) of about 150 miles and apogees (the point in the orbit furthest from the Earth) of about 600 miles.  They have infrared imagery capability, including a thermal infrared imagery capability, and thus allow imagery in darkness.  They also carry the Improved CRYSTAL Metric System (ICMS), which codes returned imagery, making it easier to map and providing details such as relative dimensions of objects on the ground.  These advanced satellites can carry more fuel than the original models.  Their life span may even be eight years.

Declassified KH-11 photographs that have been actively used in policy formulation and briefings include photographs of the Zhawar Kili Base Camp in Afghanistan, which housed training facilities for Osama bin Laden’s terrorist organization.  Then-Secretary of Defense William Cohen and Gen. Henry R. Shelton used KH-11 material to brief reporters on the U.S. cruise missile attack on the facility in 1998.

During the December 1998 Operation Desert Fox, KH-11 photographs were sent to the National Imagery and Mapping Agency, where interpreters assessed damage caused by U.S. air strikes. 

A comprehensive list of KH satellite launches is available at

http://users.ox.ac.uk/cgi-bin/safeperl/daveh/satellite.

The ninth and final KH-11 satellite was launched in 1988.  The KH-12 program was begun soon after.

KH12 (Improved Crystal)  The distinguishing difference between the KH-12 and its predecessor is the additional amount of propellant—the fuel-carrying capacity of the KH-12 is up to 7 tons of fuel.  This contributes to a 4-ton increase in total weight over the KH-11 and also prolongs the operating life of the satellite and provides unique maneuver capability.  The KH-12 can adjust its orbit to provide coverage of areas that are of particular interest, and can maneuver to avoid anti-satellite interceptors — powered by a large rocket engine attached to a frame that also resembles the Hubble Space Telescope.  About 4.5 meters in diameter, it is over 15 meters long and can be serviced, refueled, and launched by the Shuttle, although so far all have been launched by the Titan 3 expendable launch vehicle. 

This satellite has sophisticated optics that digitally enhance images before relaying them to Earth, and can provide full-spectrum IMINT data in “real time” (virtually instantaneously).  It travels low and fast in a near-polar, sun-synchronous orbit (it passes over a given point at the same time each day).  This makes it easier to detect changes taking place in the target area by comparing one day’s photos to another.  However, it also makes its arrival predictable to countries that possess good intelligence on U.S. satellite paths, leaving open the possibility of deception or simply "laying low" for a few minutes while the satellite passes overhead.  One way to avoid this predictability is to use its on-board fuel to change its orbit or to reduce its speed temporarily. 

Optical sensors and electronic cameras provide real-time transmission of images to ground stations via Milstar relay satellites.  These sensors operate in visible and near infrared light; they can also detect heat sources using thermal infrared.  These sensors most likely use low-light-level image intensifiers to provide images during darkness.  KH-12’s have advanced infrared capability useful in detecting camouflage, looking at buried structures.  By looking at temperature differences between objects, analysts can determine such things as which factories are operational or whether tank engines have been running recently.  Its image resolution approaches 10 centimeters. 

KH13  An electro-optical/IR satellite, it is an improved version of the KH12 that, unlike previous models, is undetectable by radar or infrared sensors as a safeguard against the possible use of anti-satellite weapons.

8X  The 8X was launched in May 1999 in the first of a likely series of 24 multi-function satellites that will eventually cover the globe, passing over any given spot of the planet every 15 minutes.  Featuring superior optics, these satellites are typically sent into a high "Molniya" orbit, an elongated, elliptical path where the satellite's speed slows down dramatically at the apogee.  Its high quality sensors compensate for the longer ranges resulting from its higher altitude.  It also has an adjustable dwell capability, making it useful for real-time tactical battlefield observation.  One of the drawbacks, however, is the less frequent, elliptical orbit, which means that a target will have a longer window of time in which people or vehicles can maneuver unobserved.  The 8X carries significantly larger fuel tanks than the KH series and can be refueled by the Space Shuttle.  Each adjustment to its orbit will burn up a large portion of fuel, however, due to the satellite's enormous mass.

LACROSSE

(The project to develop a space-based imaging radar satellite began in 1976.  The prototype, Indigo, was launched in January 1982.  The first operational Lacrosse was launched from the Shuttle in December 1998, and the name Lacrosse is probably not used anymore.)

The Lacrosse radar imaging satellite is an active radar satellite optimized for tactical and strategic military targets partly due to a sophisticated imaging process that involves Synthetic Aperture Radar (SAR), making it capable of resolving images to within 1 meter.  Although the resolution is not as high as the KH series, Lacrosse is an all-weather, day-night satellite.  It is able t detect and target large objects like ships and aircraft.  Lacrosse also uses other radar emissions such as GMTI to track moving vehicles, locate field bunkers up to three meters underground and submerged submarines at periscope depth (40 to 50 feet).  The NRO tries to keep two Lacrosse systems in orbit at all times, with one usually tasked for oceanic surveillance.  Currently, Lacrosse 2, 3, and 4 are believed to be in orbit based on observations by amateur astronomers.  They have a characteristic orange hue as a result of the extensive use of orange colored kapton thermal insulation.  Other distinguishing features are the very large radar antenna and the solar panels used to provide electrical power its imaging equipment.  These solar arrays reportedly have a wingspan of almost 50 meters, which suggests power available to the radar in the range of 10-20 kilowatts.  It has no significant dwell capability.

Lacrosse satellites orbit the Earth 12-14 times a day and carry a modest amount of on-board propellant for orbit adjustments.  As mentioned, the main attribute of Lacrosse is the image sensor, used to beam microwave energy to the ground.  Rows and columns of small transmitting and receiving elements cover the 48 foot long, 12 foot wide rectangular antenna, helping Lacrosse pick up the return signals that are reflected into space.  This allows the satellite to “see” objects on Earth that would otherwise be obscured by cloud cover and darkness.  Lacrosse records a series of snapshots rather than a constant stream of images.  The angle of rotation of the lens is such that it will have a small blind spot between each revolution that can only be covered by shifting to a new orbit.  Thus, an orbit that has been optimized for one target will not always cover a second.

Lacrosse most likely has a number of different radar scanning modes, some providing high resolution coverage of small areas, and others lower resolution coverage of larger areas.  Extensive computer power is needed to process Lacrosse’s data, which implies a several hundred megabits-per-second data transfer rate to ground stations. 

The name “Onyx” is associated with the fourth Lacrosse, launched on Aug. 17, 2000.  Most recently, the name “Vega” has been attached to the Lacrosse program.

Recent Vega missions have included providing imagery for bomb damage assessments of the consequences of Navy Tomahawk missile attacks on Iraqi air defense installations in September 1996, monitoring Iraqi weapons storage sites, and tracking troop movements.  Vega photographed the Shifa Pharmaceutical Plant in Sudan that was hit in the U.S. retaliatory strikes after the Embassy bombings in 1998.

ADVANCES IN ANALYSIS

One of the most significant advances in IMINT may have to do not with the platform in space but with the manipulation of the digital data derived from these satellites.  The National Imagery and Mapping Agency, which was set up to centralize the research, development, and analysis of satellite imagery, can now configure data in three-dimensional format.  The value added is not just in war fighting, but also in mission rehearsals of military and intelligence operations.  Envisions, 3D animations of terrain and landscapes, are computer-generated animations that help policy-makers gain both diplomatic leverage in negotiations (as in the animations of Serbian landscape used at the Bosnian peace accords) and to understand problems faced by peacekeepers or soldiers prior to deployment. 

MOST RECENT LAUNCHES

A payload for the National Reconnaissance Office was launched from Cape Canaveral on Oct. 10, 2001. Carried aboard an Atlas, the satellite was placed into a transfer orbit by the rocket's upper stage. Its stationary position is stated at 22,300 miles above the equator, indicating that it is either a signals intelligence satellite or a newer and smaller version of a data relay satellite used to pass information from other satellites to ground stations. (Florida Today). Aviation Week and Space Technology magazine reported that the payload is a relay satellite that could be used to route data involved in anti-terrorism operations or intelligence data related to actions in Afghanistan.

A payload was launched for the National Reconnaissance Office on October 5, 2001. It was most likely an imaging satellite, and was launched aboard a Lockheed Martin Titan IVB rocket.

Another national security payload was launched by National Reconnaissance Office on a Lockheed Martin Atlas IIAS rocket on Sept. 8, 2001, from Space Launch Complex 3E at Vandenberg AFB, Calif.  The payload is believed to be the first of a new series of naval electronic intelligence satellites. 

Sources:  Federation of American Scientists; MSNBC; Jonathan’s Space Report; Battlefront.com;  Satobs.org;  National Reconnaissance Office;  Cosmiverse.com; National Security Archive Electronic Briefing Book No. 13- U.S. Satellite Imagery, 1960-1999 by Jeffrey T. Richelson; United States Air Force Space Command; Heavens-Above.com; http://users.ox.ac.uk/cgi-bin/safeperl/daveh/satellite

Emily Clark

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