
A reconnaissance satellite or intelligence satellite (commonly, although unofficially, referred to as a spy satellite) is an
Earth observation satellite
An Earth observation satellite or Earth remote sensing satellite is a satellite used or designed for Earth observation (EO) from orbit, including spy satellites and similar ones intended for non-military uses such as environmental monitoring, me ...
or
communications satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Rad ...
deployed for
military
A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. Militaries are typically authorized and maintained by a sovereign state, with their members identifiable by a d ...
or
intelligence
Intelligence has been defined in many ways: the capacity for abstraction, logic, understanding, self-awareness, learning, emotional knowledge, reasoning, planning, creativity, critical thinking, and problem-solving. It can be described as t ...
applications.
The first generation type (i.e.,
Corona and
Zenit) took photographs, then ejected canisters of
photographic film
Photographic film is a strip or sheet of transparent film base coated on one side with a gelatin photographic emulsion, emulsion containing microscopically small light-sensitive silver halide crystals. The sizes and other characteristics of the ...
which would descend back down into Earth's atmosphere. Corona capsules were
retrieved in mid-air as they floated down on
parachute
A parachute is a device designed to slow an object's descent through an atmosphere by creating Drag (physics), drag or aerodynamic Lift (force), lift. It is primarily used to safely support people exiting aircraft at height, but also serves va ...
s. Later, spacecraft had digital imaging systems and downloaded the images via
encrypted radio links.
In the United States, most information available about reconnaissance satellites is on programs that existed up to 1972, as this information has been
declassified due to its age. Some information about programs before that time is still
classified information
Classified information is confidential material that a government deems to be sensitive information which must be protected from unauthorized disclosure that requires special handling and dissemination controls. Access is restricted by law or ...
, and a small amount of information is available on subsequent missions.
A few up-to-date reconnaissance satellite images have been declassified on occasion, or leaked, as in the case of
KH-11
The KH-11 KENNEN (later renamed CRYSTAL,p.199-200 then Evolved Enhanced CRYSTAL System, and codenamed 1010 and Key Hole) is a type of reconnaissance satellite first launched by the American National Reconnaissance Office (NRO) in December 19 ...
photographs which were sent to ''
Jane's Defence Weekly'' in 1984,
or US President
Donald Trump
Donald John Trump (born June 14, 1946) is an American politician, media personality, and businessman who is the 47th president of the United States. A member of the Republican Party (United States), Republican Party, he served as the 45 ...
tweeting a classified image of the aftermath of a failed test of Iran's
Safir rocket in 2019.
History
On 16 March 1955, the
United States Air Force
The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its ori ...
officially ordered the development of an advanced reconnaissance satellite to provide continuous surveillance of "preselected areas of the Earth" in order "to determine the status of a potential enemy's war-making capability".
During the mid-late 1950s, both the United States and the Soviet Union took interest into reconnaissance satellites. The United States began the
CORONA project, which encompassed several series of launches starting in 1959 and ending in 72. This program was made a priority to photograph denied areas, replace the
U-2, and due to public concern about a technological gap between the West and the Soviet Union. It was expedited significantly after the shooting of a U-2 in 1960.
Meanwhile, in the Soviet Union, a decree that authorized the development of sputnik apparently authorized a program for a satellite to be used for photo reconnaissance. This design evolved into Vostok, while another version became Zenit, which was an unmanned reconnaissance satellite. Zenit was launched from 1961 to 1994, however the last flight in 1994 was as a test payload.
Both the CORONA and Zenit satellites had to be recovered in order to access the used film, making them distinct from future reconnaissance satellites that could transmit photos without returning film to earth.
Types
There are several major types of reconnaissance satellite.
;Missile early warning
:Provides warning of an attack by detecting
ballistic missile
A ballistic missile is a type of missile that uses projectile motion to deliver warheads on a target. These weapons are powered only during relatively brief periods—most of the flight is unpowered. Short-range ballistic missiles (SRBM) typic ...
launches. Earliest known are
Missile Defense Alarm System.
;Nuclear explosion detection
:
Detects nuclear detonation from space.
Vela is the earliest known.
;Electronic reconnaissance
:
Signals intelligence
Signals intelligence (SIGINT) is the act and field of intelligence-gathering by interception of ''signals'', whether communications between people (communications intelligence—abbreviated to COMINT) or from electronic signals not directly u ...
, intercepts stray
radio
Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connec ...
waves.
SOLRAD is the earliest known.
[ ]
;Optical imaging surveillance
:
Earth imaging satellites.
Satellite images can be a survey or close-look
telephoto.
Corona is the earliest known.
Spectral imaging is commonplace.
;Radar imaging surveillance
:Most
space-based radars use
synthetic-aperture radar. Can be used at night or through
cloud cover. Earliest known are the Soviet
US-A
Upravlyaemy Sputnik Aktivnyy ( for Controlled Active Satellite), or US-A, also known in the Western world as Radar Ocean Reconnaissance Satellite or RORSAT ( GRAU index 17F16K), was a series of 33 Soviet reconnaissance satellites. Launched betwe ...
series.
Missions
Examples of reconnaissance satellite missions:
* High resolution photography (
IMINT)
* Measurement and Signature Intelligence (
MASINT)
* Communications eavesdropping (
SIGINT)
* Covert communications
* Monitoring of
nuclear test ban compliance (see
National Technical Means)
* Detection of missile launches
On 28 August 2013, it was thought that "a $1-billion high-powered spy satellite capable of snapping pictures detailed enough to distinguish the make and model of an automobile hundreds of miles below"
was launched from California's Vandenberg Air Force Base using a Delta IV Heavy launcher, America's highest-payload space launch vehicle at the time.
On 17 February 2014, a Russian Kosmos-1220 originally launched in 1980 and used for naval missile targeting until 1982, made an uncontrolled
atmospheric entry
Atmospheric entry (sometimes listed as Vimpact or Ventry) is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. Atmospheric entry may be ''uncontrolled entr ...
.
Benefits
During the 1950s, a Soviet hoax had led to American fears of a
bomber gap. In 1968, after gaining satellite photography, the United States' intelligence agencies were able to state with certainty that "No new
ICBM
An intercontinental ballistic missile (ICBM) is a ballistic missile with a range (aeronautics), range greater than , primarily designed for nuclear weapons delivery (delivering one or more Thermonuclear weapon, thermonuclear warheads). Conven ...
complexes have been established in the USSR during the past year". President
Lyndon B. Johnson told a gathering in 1967:
During his
1980 State of the Union Address, President
Jimmy Carter
James Earl Carter Jr. (October 1, 1924December 29, 2024) was an American politician and humanitarian who served as the 39th president of the United States from 1977 to 1981. A member of the Democratic Party (United States), Democratic Party ...
argued that all of humanity benefited from the presence of American spy satellites:
Reconnaissance satellites have been used to enforce human rights, through the
Satellite Sentinel Project
The Satellite Sentinel Project (SSP) was conceived by George Clooney and Enough Project co-founder John Prendergast during their October 2010 visit to South Sudan. Through the use of satellite imagery, SSP provides an early warning system ...
, which monitors atrocities in
Sudan
Sudan, officially the Republic of the Sudan, is a country in Northeast Africa. It borders the Central African Republic to the southwest, Chad to the west, Libya to the northwest, Egypt to the north, the Red Sea to the east, Eritrea and Ethiopi ...
and
South Sudan
South Sudan (), officially the Republic of South Sudan, is a landlocked country in East Africa. It is bordered on the north by Sudan; on the east by Ethiopia; on the south by the Democratic Republic of the Congo, Uganda and Kenya; and on the ...
.
Additionally, companies such as
GeoEye and
DigitalGlobe have provided commercial satellite imagery in support of natural disaster response and humanitarian missions.
In fiction
Spy satellites are commonly seen in
spy fiction
Spy fiction is a genre of literature involving espionage as an important context or plot device. It emerged in the early twentieth century, inspired by rivalries and intrigues between the major powers, and the establishment of modern intellig ...
and
military fiction
Military fiction is a subgenre of science fiction or alternate history, focusing on military activities, such as war, battles, combat, fighting; or military life.
Classes of military fiction
Types of military fiction include:
* War novels, ...
. Some works of fiction that focus specifically on spy satellites include:
* ''
Body of Lies'' (2008)
* ''
Enemy of the State'' (1998)
* ''
Ice Station Zebra'' (1968)
* ''
The OMAC Project'' (2005)
* ''
Parmanu: The Story of Pokhran'' (2018)
* ''
Patriot Games'' (1987)
See also
*
Aerial reconnaissance
Aerial reconnaissance is reconnaissance for a military or Strategy, strategic purpose that is conducted using reconnaissance aircraft. The role of reconnaissance can fulfil a variety of requirements including Artillery observer, artillery spott ...
*
Defense Support Program (U.S.)
*
European Union Satellite Centre
*
List of intelligence gathering disciplines
*
List of Kosmos satellites
*
National Reconnaissance Office (U.S.)
*
Satcom on the Move
References
Further reading
*
*
*
External links
FAS Intelligence Resource Program – Imagery Intelligence (IMINT)
*
ttps://web.archive.org/web/20091027181013/http://rst.gsfc.nasa.gov/ Military Intelligence Satellites(NASA, remote sensing tutorial)
{{DEFAULTSORT:Spy Satellite
Espionage devices
Satellites by type
Earth observation satellites