A zombie satellite is a

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope ...

that begins communicating again after an extended period of inactivity. It is a type of

space debris Space debris (also known as space junk, space pollution, space waste, space trash, or space garbage) are defunct human-made objects in space—principally in Earth orbit—which no longer serve a useful function. These include derelict spacecr ...

, which describes all defunct human-made objects in

outer space Outer space, commonly shortened to space, is the expanse that exists beyond Earth and its atmosphere and between celestial bodies. Outer space is not completely empty—it is a near-perfect vacuum containing a low density of particles, pred ...

. At the end of their

service life A product's service life is its period of use in service. Several related terms describe more precisely a product's life, from the point of manufacture, storage, and distribution, and eventual use. Service life has been defined as "a product's ...

, the majority of satellites suffer from

orbital decay Orbital decay is a gradual decrease of the distance between two orbiting bodies at their closest approach (the periapsis) over many orbital periods. These orbiting bodies can be a planet and its satellite, a star and any object orbiting it, or ...

and are destroyed by the heat of

atmospheric entry Atmospheric entry 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. There are two main types of atmospheric entry: ''uncontrolled entry'', such as the ent ...

. Zombie satellites, however, maintain a stable orbit but are either partially or completely inoperable, preventing operators from communicating with them consistently.

History

Transit 5B-5

One of the oldest known zombie satellites is Transit 5B-5. It was launched in 1965 as part of the

Transit Transit may refer to: Arts and entertainment Film * ''Transit'' (1979 film), a 1979 Israeli film * ''Transit'' (2005 film), a film produced by MTV and Staying-Alive about four people in countries in the world * ''Transit'' (2006 film), a 2006 ...

system, one of the first

satellite navigation A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning. It allows satellite navigation devices to determine their location (longitude, latitude, and altitude/elevation) to high pr ...

systems. Transit 5B-5 is nuclear powered and still in a stable

polar orbit A polar orbit is one in which a satellite passes above or nearly above both poles of the body being orbited (usually a planet such as the Earth, but possibly another body such as the Moon or Sun) on each revolution. It has an inclination of about ...

, though operators are unable to control it.

LES-1

LES-1 Lincoln Experimental Satellite 1, also known as LES-1, was a communications satellite, the first of nine in the Lincoln Experimental Satellite program. Launched by the United States Air Force (USAF) on February 11, 1965, it pioneered many then- ...

, also known as

Lincoln Experimental Satellite The Lincoln Experimental Satellite series was designed and built by Lincoln Laboratory at Massachusetts Institute of Technology between 1965 and 1976, under USAF sponsorship, for testing devices and techniques for satellite communication. Developm ...

1, was a

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. C ...

launched by the

United States Air Force The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...

on February 11, 1965 to study the use of

Super High Frequency Super high frequency (SHF) is the ITU designation for radio frequencies (RF) in the range between 3 and 30 gigahertz (GHz). This band of frequencies is also known as the centimetre band or centimetre wave as the wavelengths range from one to ...

radio transmissions. It never achieved optimal orbit and was out of contact for more than 40 years before spontaneously resuming transmissions in 2012.

AMSAT-OSCAR 7

AMSAT-OSCAR 7 AMSAT-OSCAR 7, or AO-7, is the second Phase 2 amateur radio satellite constructed by the Radio Amateur Satellite Corporation or AMSAT. It was launched into Low Earth Orbit on November 15, 1974 and remained operational until a battery failure in 1 ...

is an amateur-radio communications satellite which was launched into Low Earth Orbit on November 15, 1974 and remained operational until a battery failure in 1981. Then after 21 years of apparent silence, the satellite was heard again on June 21, 2002 – 27 years after launch.

Galaxy 15

Galaxy 15 Galaxy 15 is an American telecommunications satellite which is owned by Intelsat. It was launched for and originally operated by PanAmSat, and was subsequently transferred to Intelsat when the two companies merged in 2006. It was originally posit ...

is a U.S.

telecommunications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. C ...

launched in 2005. In April 2010, only five years into a planned 15 year mission, its operator,

Intelsat Intelsat S.A. (formerly INTEL-SAT, INTELSAT, Intelsat) is a multinational satellite services provider with corporate headquarters in Luxembourg and administrative headquarters in Tysons Corner, Virginia, United States. Originally formed as In ...

, lost control of the satellite and it drifted out of its

orbital slot A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude ...

. Several months later, on December 27, 2010, the satellite rebooted itself and began responding to commands again. Intelsat re-positioned it back to its original orbital slot in April 2011.

IMAGE

Launched in 2000, IMAGE (Imager for Magnetopause-to-Aurora Global Exploration), a

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

spacecraft studying the Earth's

magnetosphere In astronomy and planetary science, a magnetosphere is a region of space surrounding an astronomical object in which charged particles are affected by that object's magnetic field. It is created by a celestial body with an active interior dynam ...

, unexpectedly ceased operations in December 2005. It was a zombie satellite until Scott Tilley, an amateur radio operator living in Canada tracked it down in January 2018. On February 25, contact with IMAGE was again lost. It was reestablished in March but lost again in August. NASA is currently evaluating a recovery mission.

LES-5

On March 24, 2020, contact with another lost Lincoln Experimental Satellite, LES-5, was made by Scott Tilley. The satellite is only in operation when its solar panels are receiving sunlight.

References

{{Reflist Satellites Space debris