The Space Safety Programme, formerly the Space Situational Awareness (SSA) programme, is the

European Space Agency The European Space Agency (ESA) is a 23-member International organization, international organization devoted to space exploration. With its headquarters in Paris and a staff of around 2,547 people globally as of 2023, ESA was founded in 1975 ...

's (ESA) initiative to monitor hazards from space, determine their risk, make this data available to the appropriate authorities and where possible, mitigate the threat.

Programme

The SSA Programme was designed to support Europe's independent space access and utilization through the timely and accurate information delivery regarding the space environment, particularly hazards to both in-orbit and ground infrastructure. In 2019 it evolved into the present Space Safety Programme with an expanded focus, also including missions and activities to mitigate and prevent dangers from space. The programme is split into four main segments: *

Space weather Space weather is a branch of space physics and aeronomy, or heliophysics, concerned with the varying conditions within the Solar System and its heliosphere. This includes the effects of the solar wind, especially on the Earth's magnetosphere, ion ...

: monitoring the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

, the

solar wind The solar wind is a stream of charged particles released from the Sun's outermost atmospheric layer, the Stellar corona, corona. This Plasma (physics), plasma mostly consists of electrons, protons and alpha particles with kinetic energy betwee ...

, and in 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 Dynamo ...

ionosphere The ionosphere () is the ionized part of the upper atmosphere of Earth, from about to above sea level, a region that includes the thermosphere and parts of the mesosphere and exosphere. The ionosphere is ionized by solar radiation. It plays ...

and

thermosphere The thermosphere is the layer in the Earth's atmosphere directly above the mesosphere and below the exosphere. Within this layer of the atmosphere, ultraviolet radiation causes photoionization/photodissociation of molecules, creating ions; the ...

, that can affect spaceborne and ground-based infrastructure or endanger human life or health. This data is processed by th
Space Weather Service Network
and made available freely via th
Space Weather Portal
Upcoming missions such as

Vigil A vigil, from the Latin meaning 'wakefulness' ( Greek: , or ), is a period of purposeful sleeplessness, an occasion for devotional watching, or an observance. The Italian word has become generalized in this sense and means 'eve' (as in "on t ...

will contribute to this monitoring system, allowing for timely warnings. * Planetary Defence: detecting natural objects, such as

asteroids An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...

and

comets A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or coma surrounding the nucleus, an ...

, which can potentially impact Earth, gathering observations from telescopes around the world and plotting their path through the sky to calculate the impact risk, as well as coordinating with the international community the response to a possible impactor, through groups such as th
International Asteroid Warning Network (IAWN)
and th

ESA will soon launch the Hera mission, a follow-up to NASA's

DART mission The Double Asteroid Redirection Test (DART) was a NASA space mission aimed at testing a method of planetary defense against near-Earth objects (NEOs). It was designed to assess how much a spacecraft impact deflects an asteroid through its tran ...

which performed the first kinetic impact test of Planetary Defence on 26 September 2022. Hera will rendezvous with the impacted Didymos binary asteroid system to study the crater formed, the dust plume released and more.
Space debris
Tracking active and inactive

satellite A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...

s and

space debris Space debris (also known as space junk, space pollution, space waste, space trash, space garbage, or cosmic debris) are defunct human-made objects in spaceprincipally in Earth orbitwhich no longer serve a useful function. These include dere ...

to better understan
the debris environment
providing data, analysis and advice to spacecraft engineers to perform collision avoidance manoeuvres as well as developing a system o
automated collision avoidance
The space debris office also works with the international community on norms and standards for the sustainable future of space.
Clean Space
systematically considering the entire life-cycle of space activities, from the early stages of conceptual design to the mission’s end of life – and even beyond, to removal of space debris. ESA Clean Space include
EcoDesign
embedding environmental sustainability within space mission design
Management of end-of-life
developing technologies to prevent the creation of future debris
in-orbit servicing
active debris removal, removing spacecraft from orbit and demonstrating in-orbit servicing of spacecraft. The first mission to remove a piece of space debris from orbit will be the ESA-commissioned Clearspace-1. The Space Safety programme is being implemented as an optional ESA programme with financial participation by 14 Member States. The programme started in 2009 and its mandate was extended until 2019. The second phase of the programme received €46.5 million for the 2013–2016 period.

Space weather segment

The main objective of the space weather segment (SWE) is to detect and forecast of

space weather Space weather is a branch of space physics and aeronomy, or heliophysics, concerned with the varying conditions within the Solar System and its heliosphere. This includes the effects of the solar wind, especially on the Earth's magnetosphere, ion ...

events, avoid adverse effect on European space assets and ground-based infrastructure. To achieve that, the segment will focus on delivery of real-time space weather information, forecasts and warnings, supported by a data archive, applications and services. Assets currently available for the segment consist of multiple ground-based and spaceborne sensors monitoring the Sun,

and Earth's

and

. These include the PROBA2 satellite and the

Kanzelhoehe Solar Observatory The Kanzelhoehe Solar Observatory or KSO is an astronomical observatory affiliated with the Institute of Geophysics, Astrophysics and Meteorology out of the University of Graz.Meteorological and Geoastrophysical Abstracts. United States, America ...

. The segment is jointly coordinated by the SWE Data Centre located at the

ESTRACK The European Space Tracking (ESTRACK) network consists of a number of ground-based space-tracking stations belonging to the European Space Agency (ESA), and operated by the European Space Operations Centre (ESOC) in Darmstadt, Germany. The st ...

Redu Station Redu Station is an ESTRACK radio antenna station for communication with spacecraft. The station is located in Wallonia, about one kilometer away from the village of Redu, Belgium, where it has been tracking satellites since 1968. The ground term ...

and the SSA Space Weather Coordination Centre (SSCC), both in

Belgium Belgium, officially the Kingdom of Belgium, is a country in Northwestern Europe. Situated in a coastal lowland region known as the Low Countries, it is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeas ...

Near-Earth object segment

The

near-Earth object A near-Earth object (NEO) is any small Solar System body orbiting the Sun whose closest approach to the Sun ( perihelion) is less than 1.3 times the Earth–Sun distance (astronomical unit, AU). This definition applies to the object's orbit a ...

segment aims to deliver monitoring and warning of potential Earth impactors and tracking of newly discovered objects. The segment's current assets consist of a mixture of professional and amateur telescopes, including the

OGS Telescope The ESA Optical Ground Station (''OGS Telescope'' or ''ESA Space Debris Telescope'') is the European Space Agency's ground based Astronomical observatory, observatory at the Teide Observatory on Tenerife, Spain, built for the observation of space ...

, that are supported by tracking databases. The plans are to create a fully integrated system supporting alerts for civil authorities, including the

NEOSTEL The Near Earth Object Survey TELescope (NEOSTEL), also known as "Flyeye", is an astronomical survey and early-warning system for detecting near-Earth objects sized and above a few weeks before they impact Earth. NEOSTEL is a project founded b ...

flyeye telescope due for completion in 2020. The segment is operated by the SSA NEO Coordination Centre located at the

ESA Centre for Earth Observation The ESA Centre for Earth Observation (also known as the European Space Research Institute or ESRIN) is a research centre belonging to the European Space Agency (ESA), located in Frascati (Rome) Italy. It is dedicated to research involving ear ...

, Italy.

Space surveillance and tracking segment

The SST segment's primary goal is the detection, cataloguing and orbit prediction of objects orbiting the Earth. It is part of an effort to avoid collisions between orbiting satellites and debris, provide safe reentries, detect on-orbit explosions, assist missions at launch, deployment and end-of-life and overall reduce cost of space access. The segment currently relies on existing European radar and optical systems. Some of its assets are existing

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 ...

and

optical telescopes An optical telescope gathers and focuses light mainly from the visible part of the electromagnetic spectrum, to create a magnified image for direct visual inspection, to make a photograph, or to collect data through electronic image sensors. ...

, with now serving a secondary role for tracking space debris. The radar-based SST assets are split into two categories: surveillance and tracking systems. SSA SST radar systems include: * Surveillance ** Northern Cross transient radio telescope located at the

Medicina Radio Observatory The Medicina Radio Observatory is an astronomical observatory located 30 km from Bologna, Italy. It is operated by the Institute for Radio Astronomy of the INAF, National Institute for Astrophysics (INAF) of the government of Italy. The sit ...

, serving as a receiver in

bistatic radar Bistatic radar is a radar system comprising a transmitter and receiver that are separated by a distance comparable to the expected target distance. Conversely, a conventional radar in which the transmitter and receiver are co-located is called ...

system **

RAF Fylingdales Royal Air Force Fylingdales (RAF Fylingdales) is a Royal Air Force List of Royal Air Force stations, station on Snod Hill in the North York Moors, England. Its motto is ''Vigilamus'' ("We are watching"). It is a radar Military base, base and i ...

's three face AN/FPS-132 Upgraded Early Warning

phased array radar A phaser is an electronic sound processor used to filter a signal by creating a series of peaks and troughs in the frequency spectrum. The position of the peaks and troughs of the waveform being affected is typically modulated by an interna ...

, serving as a monostatic system **

French Air Force The French Air and Space Force (, , ) is the air force, air and space force of the French Armed Forces. Formed in 1909 as the ("Aeronautical Service"), a service arm of the French Army, it became an independent military branch in 1934 as the Fr ...

bistatic radar-based

space surveillance Space domain awareness is the study and monitoring of satellites orbiting the Earth. It involves the detection, tracking, cataloging and identification of artificial objects, i.e. active/inactive satellites, spent rocket bodies, or fragmentatio ...

system GRAVES * Tracking **

CAMRa The Campaign for Real Ale (CAMRA) is an independent voluntary consumer organisation headquartered in St Albans, which promotes real ale, real cider, cider and perry and traditional British pubs and clubs. History The organisation was founde ...

25-meter steerable

parabolic dish A parabolic (or paraboloid or paraboloidal) reflector (or dish or mirror) is a reflective surface used to collect or project energy such as light, sound, or radio waves. Its shape is part of a circular paraboloid, that is, the surface generated ...

S-band The S band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz). Thus it crosses the convention ...

radar located at the Chilbolton Observatory **

EISCAT EISCAT (European Incoherent Scatter Scientific Association) operates three incoherent scatter radar systems in Northern Scandinavia and Svalbard. The facilities are used to study the interaction between the Sun and the Earth as revealed by dist ...

scatter radar capable of 3D monitoring of the

atmosphere An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosph ...

and

** TIRA 34-meter parabolic dish with an

L-band The L band is the Institute of Electrical and Electronics Engineers (IEEE) designation for the range of Frequency, frequencies in the radio spectrum from 1 to 2 gigahertz (GHz). This is at the top end of the ultra high frequency (UHF) band, at t ...

tracking radar and a

Ku-band The Ku band () is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under" (originally ), because it is the lower part of the original NATO K band ...

imaging radar Imaging radar is an application of radar which is used to create two-dimensional images, typically of landscapes. Imaging radar provides its light to illuminate an area on the ground and take a picture at radio wavelengths. It uses an antenna and ...

SSA SST optical surveillance and tracking assets include: * Surveillance ** OLS telescope at the

Observatorio Astronómico de Mallorca The Astronomical Observatory of Mallorca (, OAM) is an observatory just south of Costitx, Mallorca, Spain. The observatory was inaugurated in May 1991 and was the first astronomical center in the Balearic Islands autonomous community and provin ...

** Starbrook and Starbrook north located at Troodos Station ** Fabra-ROA telescope (TFRM) at Serra del Montsec ** ZimSMART

robotic telescope A robotic telescope is an astronomical telescope and detector system that makes observations without the intervention of a human. In astronomical disciplines, a telescope qualifies as robotic if it makes those observations without being operated ...

* Tracking **

Satellite laser ranging Satellite laser ranging (SLR) is a method to measure the distance to satellites in a geocentric orbit. It consists of an astronomical observatory equipped with a laser that sends ultrashort pulses of light. The pulses hit the satellite and boun ...

station Graz at Lustbühel Observatory ** Matera Laser Ranging Observatory (MLRO) in Italy **

at the

Teide Observatory Teide Observatory (), IAU code 954, is an astronomical observatory on Mount Teide at , located on Tenerife, Spain. It has been operated by the Instituto de Astrofísica de Canarias since its inauguration in 1964. It became one of the first major ...

** TAROT and TAROT-South robotic telescope at the

La Silla Observatory La Silla Observatory is an astronomical observatory in Chile with three telescopes built and operated by the European Southern Observatory (ESO). Several other telescopes are also located at the site and are partly maintained by ESO. The observato ...

** ZIMLAT telescope at the

Zimmerwald Observatory The Zimmerwald Observatory () is an astronomical observatory owned and operated by the AIUB, the Astronomical Institute of the University of Bern. Built in 1956, it is located at Zimmerwald, 10 kilometers south of Bern, Switzerland. Numerous com ...

** ESA Flyeye

Telescope A telescope is a device used to observe distant objects by their emission, Absorption (electromagnetic radiation), absorption, or Reflection (physics), reflection of electromagnetic radiation. Originally, it was an optical instrument using len ...

at Sicily, Italy As part of the SSA Programme new, dedicated surveillance radar supported by optical sensors systems will be developed. The segment is coordinated by the Space Surveillance Test & Validation (SSTC) Centre located at the ESAC in

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

. Close approaches of

Near-Earth object A near-Earth object (NEO) is any small Solar System body orbiting the Sun whose closest approach to the Sun ( perihelion) is less than 1.3 times the Earth–Sun distance (astronomical unit, AU). This definition applies to the object's orbit a ...

s and near earth asteroids are reported by ESA through the space situational awareness center.

References

External links