REMOTE SENSING

Military surveillance

Space is clearly the ideal place for gathering information for military purposes and, from the very start, many Earth bservation satellites have served rather more confidential causes than others. Such military satellites are also distinctive for their technical and operating characteristics.

Preparing the optical component of two future Pléiade satellites in the Thales Alenia Space clean rooms in Cannes (FR). Preparing the optical component of two future Pléiade satellites in the Thales Alenia Space clean rooms in Cannes (FR).
©Thales-Alenia Space

Although when it comes to intelligence gathering the military are very discreet, remote sensing from space is clearly a vital tool for them. Virtually from the start of the space adventure, just 50 years ago, the major powers – the United States and Soviet Union – developed and launched spy satellites.

They were developed to provide high spectral and spatial resolution observations of the activities of other countries. Some of these devices were also developed to identify nuclear explosions or for the early detection of the launch of enemy ballistic missiles.

In 1959, the US Army was the first to put experimental Earth observation satellites into orbit (Discoverer and Samos). These pioneers were followed by dozens of spy satellites of the Key-Hole (KH) variety. The Soviet Union was quick to do the same with its prototype Kosmos-4 (1962) and many successors.

One mission, one film

These early military remote sensing devices differed from other observation satellites in terms of their very low orbit, short space life (from a few days to a few weeks) and filming system. They were in fact equipped with no more than sophisticated cameras. Launched into an orbit selected in line with the objective to be studied, they set their film running and, when the film ran out, they returned to Earth, mission accomplished. The film was then developed on the ground and the images studied.

The technical progress made over the past four decades has enabled the military to acquire more sophisticated devices equipped with digital optics, infrared and radar, the latter permitting observations day and night, irrespective of cloud cover. Most significantly, these are able to transmit their images directly from space. It is thus no longer necessary to wait for their return to Earth to find out what they have seen.

What resolution?

The resolution of the sensors used by military satellites is of course confidential. The best we can do is obtain a rough estimate on the basis of the capacities shown by the most powerful civilian satellites. “In terms of spatial resolution, some civilian satellites provide very precise data, down to around 80 cm on the ground,” explains Volker Liebig, director of Earth observation programmes at ESA (European Space Agency). “There is also clearly a growing tendency for the data transmitted by civilian satellites and the orders sent out to them from ground control to be encrypted, as they are for military satellites. In a sense, this is to safeguard against hackers! Nevertheless, there are still some differences between civilian and military satellites in certain fields, such as armouring satellites against radiation or the ability of military satellites to quickly change orbit in crisis situations.

This means that military satellites consume and require access to much more fuel and must also be able to pass very frequently over the same point on the Earth’s surface to monitor an evolving situation.” After a period when remote sensing was the preserve of the United States and Russia, other nations came to acquire Earth observation devices.

In 1988 Israel launched its first Offeq satellite. More recently, China also acquired Earth observation satellites in the form of the recoverable FSW capsules and the dual-purpose (civilian and military) Zi Yuan, with the capacity to transmit data to the ground.

Europe catches up

In Europe, France began developing the Hélios optical satellites in 1995, in cooperation with Italy and Spain. Currently operational is the French Hélios-2 military programme, also in the optical field with satellites derived from the Spot civilian platform. The Hélios-2A satellite was launched in December 2004 and the images it sends back are used by the French Armed Forces but there are also partnerships with Spain and Belgium. The second satellite of this generation, Hélios-2B, is scheduled for launch in 2009 and will remain in orbit until 2014.

Germany, on the other hand, is concentrating on a constellation of military radar satellites with its Sar-Lupe programme. This is a constellation of five satellites, the first of which entered orbit in 2006.

France is currently developing twin optical observation satellites: the Pléiades constellation, consisting of two small satellites (one tonne each) with a spatial resolution of 0.7 m and field of vision of 20 km. Pléiades will provide stereoscopic acquisition capacities to meet the needs of precise cartography, especially in urban areas, and can usefully supplement aerial photography. Germany, Belgium, Italy, Spain, Sweden and Austria are all contributing in some way to this dual-purpose military and civilian programme.

Italy, meanwhile, is developing a set of four radar satellites, also for a dual purpose programme: the Cosmo SkyMed satellites, which will be in simultaneous orbit. Together, the Pléiades and Cosmo SkyMed are at the heart of the Musis (Multinational Space-based Imaging System for surveillance, reconnaissance and observation) cooperation project launched by France in 2005. This already includes Germany, Belgium, Italy, Spain and Greece as partners. The project aims to prepare for the post-Helios era. This future Earth observation system will have both optical and radar equipment and should be operational before 2014 when Hélios 2B is expected to complete its active service life.

The future of European military geospatial intelligence is already taking shape.

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The EUSC in Torrejón

Europe has acquired its own expertise to enable it to exploit the data obtained by Earth observation satellites. Located in Torrejón de Ardoz, not far from Madrid (ES), the European Union Satellite Centre (EUSC) opened in 2002. It is an agency charged with exploiting and producing information obtained from the analysis of satellite pictures of the Earth.

In particular, it aims to support EU decision-making in the field of the Common Foreign and Security Policy (CFSP) and European Security and Defence Policy (ESDP). It contributes specifically to EU crisis management operations, by providing products resulting from the analysis of satellite imagery and associated data, including aerial imagery and related services.

The EUSC products and services can also be made available to the Member States, the Commission, third countries and various international organisations (United Nations, Organisation for Security and Cooperation in Europe, North Atlantic Treaty Organisation, etc.).

The EUSC is financed by contributions from Member States and payments for services rendered. Its services contribute to specific initiatives, such as humanitarian aid missions, peacekeeping operations, the monitoring and implementation of international treaties, crisis management, control of the non-proliferation of strategic weapons of mass destruction, and certain judicial inquiries.



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