Frequently asked questions - RADARSAT Constellation Mission

The RADARSAT Constellation Mission (RCM) is the evolution of the RADARSAT program with the objective of ensuring data continuity from previous RADARSAT missions. It consists of three identical Synthetic Aperture Radar (C-Band) Earth observation satellites approximatively half the size of its predecessors.

The three-satellite configuration provides daily revisits (on average) of Canada's vast territory and maritime approaches, including the Arctic up to four times a day, as well as daily access to any point on 90% of the world's surface.

The launch of the satellites took place on June 12, 2019.

After the three RCM satellites were declared operational on November 14, 2019, data acquisition started. A portion of the data is available through the Earth Observation Data Management System (EODMS). Designed and supported by Natural Resources Canada, the system gives access to reliable Earth observation data to Canadian and international industry and the general public.

RCM data is used in a variety of areas, such as maritime surveillance, ecosystem monitoring, agriculture, climate change monitoring and helping disaster relief efforts. Learn more about RCM data.

Because the RCM has three identical spacecraft that fly together in a constellation instead of just one like RADARSAT-2, it has the capacity to view any point on 90% of the world's surface every 24 hours (except around the South Pole); offer daily images (on average) of Canada's vast land mass, oceans and coasts; and cover areas in the Arctic up to four times a day. This capacity allows for the creation of composite images that highlight changes over time, which is particularly useful for monitoring climate change, land use evolution, and even human impacts on the environment.

Contrary to RADARSAT-2, the RCM is equipped with an Automatic Identification System (AIS) receiver for ships. It can be used independently or in conjunction with the radar, allowing improved detection and tracking of vessels of interest.

Comparative table of RADARSAT-1, RADARSAT-2 and RCM system characteristics.

While RADARSAT-2 is still operational, an alternative and a successor was needed to respond to rapidly evolving needs. Fuelled by big data analytics and the growing use of artificial intelligence, among other things, the RCM is the next step for the RADARSAT program, ensuring continuous data availability to users.

MDA was the Prime Contractor for the project. As such, it was responsible for the design, construction and testing of the spacecraft, which was mainly done out of its facility in Sainte-Anne-de-Bellevue, Quebec. Magellan, based in Winnipeg, Manitoba, built the bus – or the body – of the three satellites. At the peak of the project, approximately 300 people worked on the construction of the RCM in some 50 companies across the country. In total, 125 suppliers across seven Canadian provinces played a role in the project.

Learn more about how the satellites were tested by MDA in this Ask an Expert session on Facebook.

The bus (the body) of each satellite is 3.6 m high, about the height of two average men, by 1.1 m wide and 1.7 m deep. The antenna is 6.98 m wide. The total mass of each of the three satellites at launch is 1,430 kg (approximately the weight of a black rhino). In comparison, the total mass of RADARSAT-2 is 2,200 kg.

The mission planning and operations of the RCM is conducted by the Canadian Space Agency (CSA) in collaboration with industrial partners. To fulfill this function, a state-of-the-art Satellite Operations Control Centre at CSA headquarters in Longueuil, Quebec, and a Back-up Control Facility in Ottawa, have been built.

In addition, the Department of National Defence, through the Polar Epsilon 2 project, is also set up to order, process and receive data.

The Canada Centre for Mapping and Earth Observation, a division of Natural Resources Canada, operates the network of Canadian ground stations, which transmit commands to track and receive data from the spacecraft. It also manages the SAR data archive and access to the archived SAR data through the EODMS.

Shared Services Canada is responsible for communications infrastructure between the various subsystems of the ground segment and the servers where the RCM data archives and EODMS reside.

For more details on the ground stations:

• Prince Albert, Saskatchewan; Inuvik, Northwest Territories; and Gatineau, Quebec, for S-Band command and telemetry reception as well as X-band data reception
• X-band receiving stations in Aldergrove, British Columbia; and Masstown, Nova Scotia
• Northern Ground Terminal (Kiruna station from Swedish Space Corporation) used mainly for launch, early operation and fast-tasking of the constellation

Learn more about how the RCM is controlled by watching this Ask an Expert session on Facebook.

The expected lifespan of the RCM is seven years for each satellite.

The three spacecraft are evenly spaced on the same orbital plane, separated around the globe by 32 minutes or approximately 14,600 km.

The RCM orbits Earth at an altitude of 600 km. The satellites move at 27,200 km/h and take about 96 minutes to circle the globe. The orbit of each spacecraft is maintained precisely within an orbital "tube" of 100 m in diameter.

We estimate that the Government of Canada will use approximately 250,000 RCM images per year. That is 50 times more than the first generation of RADARSAT.

As opposed to an optical sensor, which is able to detect energy naturally emitted from Earth's surface (visible light, ultraviolet rays and infrared rays) to generate images, a radar is an active sensor that provides its own energy source for imaging. That is why radar satellites can image Earth anytime, regardless of the time of day or the season. However, this capacity requires a fairly large amount of energy to adequately highlight targets. For that reason, the satellites can only take images upon request and not continuously, with a limit of 15 minutes per orbit for imaging (an orbit lasts 96 minutes).

Each satellite has a 12-day repeat cycle. In other words, each satellite flies over a given point every 12 days. However, the constellation approach offers exact revisits every four days, which means that one of the three spacecraft flies above a point every four days. By way of contrast, RADARSAT-1 and RADARSAT-2 have a 24-day exact revisit time (one satellite vs. three with the RCM).

The system is designed as a medium-resolution mission primarily dedicated to regular monitoring of broad geographic areas. This provides a "big picture" overview of Canada's land mass and proximate water areas. The system also includes high-resolution modes, primarily designed for disaster management.

Learn more about the RCM's imaging modes and system characteristics.

The data latency, from acquisition to delivery, depends on the application area and the user requirements. It varies from 10 to 30 minutes for near-real-time requests to a maximum of 24 hours for standard ones.

For example:

• For ship detection in Canadian and adjacent waters within the coverage area of Canadian ground stations: 10 minutes
• Other maritime surveillance applications: 30 minutes
• Global and Canadian disaster management applications: 2 hours
• Ecosystem monitoring applications: 24 hours

• Multi-polarization options: In addition to all the RADARSAT-2 polarimetric modes, the RCM has new compact polarization modes that involve transmitting circular polarization. These modes combine wide-swath performance with enhanced polarimetric classification capabilities.
• Multiple imaging modes: The satellites have a wide variety of imaging modes from high-resolution spotlight modes (with 1 m × 3 m resolution) suitable for imaging small areas, to wide-swath imaging modes with swaths of up to 500 km wide. The wide-swath imaging modes are suitable for broad-area maritime and land surveillance. For example, in the ship detection mode which has a 350-km imaging swath, the RCM satellites can detect ships of 25 m in length over all the maritime areas within 2,000 km of the coasts of Canada, every day.
• Automatic Identification System (AIS): Each RCM satellite carries an AIS receiver. It can be used independently or in conjunction with the radar, allowing improved detection and tracking of vessels of interest.
• Coherent Change Detection (CCD): Using a technique called interferometry, change between images can be detected on a centimetre scale. This allows detection of small motions such as ground subsidence and land use change in general.
• Applications include geo-hazard monitoring, infrastructure monitoring (such as pipelines and rail lines), and glacier motion.
• The RCM is designed to support CCD through enhanced orbit control ("tube flying"), better attitude control, and special imaging techniques designed for CCD.

The RCM satellites were launched aboard a SpaceX Falcon 9 rocket from Vandenberg Air Force Base, California, on June 12, 2019.

Data generated by the RCM enables the development of innovative information products benefitting Canadians in a number of ways. Here are a few examples:

Through more frequent ice monitoring, the RCM helps create precise sea ice maps of Canada's oceans and the Great Lakes to facilitate navigation and commercial maritime transportation, which is essential to our economy and in our daily lives.

Similarly, radar data is used to monitor changes in permafrost and ground movement to support northern communities in planning municipal infrastructure. The information enables decision makers to identify where to safely build houses as well as to plan airport runways and their operation and maintenance.

The RCM is also used to monitor the integrity of critical infrastructure like highways, overpasses and bridges, making them safer for Canadians.

Using RADARSAT-2 imagery, along with that of other satellites, Natural Resources Canada produced maps that aided Public Safety Canada's relief efforts during the severe flooding in Quebec, Ontario and New Brunswick in spring 2019. The RCM also has this capability, but with a higher revisit rate.

Radar is a powerful tool since it has the capability to view through clouds, haze and smoke, to map burn scars and is sensitive to the changes in the structural characteristics of forest ecosystems that occur due to wildfire.

Satellite data helps farmers grow crops to their full potential and produce better quality products for Canadians.

• The RCM accurately detects crop characteristics over thousands of square metres, regardless of weather conditions.
• The data is extremely useful in monitoring moisture levels in the top few centimetres of soil, assessing soil and crop health, and avoiding waste of fertilizer, pesticides and water.
• In other words, the highly accurate data collected by the RCM enables farmers to maximize crop yields while reducing energy consumption and the use of potential pollutants.

For more details on the numerous benefits of satellites, visit Satellites serving Earth.

The RCM system and its data are used first and foremost in support of Government of Canada services and needs.

Certain RCM image products are freely and openly available to users outside the Government of Canada, subject to exceptions in terms of security, privacy and confidentiality. The user profile (i.e. public or vetted user) defines the level of access to RCM image products.

The use of each image product must adhere to the accompanying User Licence Agreement.

To become a public user and access RCM image products, you need to register for an EODMS account.

Users wishing to view RCM image products, over and above those available to the general public on the EODMS, can then apply to become vetted users. They have to go through a security screening process. For more information, go to the How to become a user page.

Vetted users are from non-federal government organizations, industry and academia.

They have successfully passed a security screening process. They have been granted an account that provides increased access to archived RCM image products.

All of the details can be found on the How to become a user page.

Every user has access to the catalogue of image products through the EODMS. Their user profile (i.e. public or vetted user) determines which image products they are able to view and/or download.

Users can also view the RCM standard coverage maps, which are provided every three months. The maps are technical and show the RCM image products that are available for the previous three-month period.

Note: Not all image products identified on the RCM Standard coverage maps are publically available. Public users will be able to download the following products only: Products covering Canada Land with a 16-metre resolution or coarser, World Maritime products with a 100-metre resolution or coarser.

The CSA is the coordinator of data ordering and dissemination, whereas access to data is provided by the Canada Centre for Mapping and Earth Observation (CCMEO), a division of Natural Resources Canada. The CCMEO is also responsible for the long-term archiving of data.

Yes. The data distribution approach being implemented for the RCM is aligned with the spirit of the Directive on Open Government and the global trends in Earth observation. It provides access to image products (subject to security restrictions set out in Canadian legislation) for free to users.

RCM synthetic aperture radar (SAR) data will be made available in the form of image products, in a format readable by common image processing computer software. They will be created from the raw data acquired by the system. These image products can be further processed into value-added products and be used to provide information services.

Yes. The RCM data distribution approach, aligned with the spirit of the Directive on Open Government and the global trends in Earth observation, aims to provide access to image products (subject to security requirements set out in Canadian legislation) for free to a variety of Canadian and international users, including those from industry, government and academia.

The use of each image product must adhere to the accompanying User Licence Agreement.

Yes. To maximize the socio-economic benefits of the Government's investment in this mission, RCM image products are available free of charge and to the broadest extent possible, in order to promote the development of innovative products and services derived from SAR data. The use of each image product must adhere to the accompanying User Licence Agreement.

All Government of Canada department users are able to share RCM data and images through sharing arrangements with their respective partners.

As a founding member of the International Charter "Space and Major Disasters," the CSA provides RADARSAT-2 and RCM imagery to support rescue teams and relief efforts on the ground when disasters strike anywhere in the world.

Certain RCM image products are made available to all users, including those from foreign countries, through the EODMS. To gain access to these products, those interested must first register for an EODMS account.

If image products available to users are not sufficient, a public user may wish to apply to become a vetted user in order to gain greater access. Access to additional image products will continue to be through the EODMS website.

The use of each RCM image product must adhere to the accompanying User Licence Agreement.

The CSA is making science data about our planet publicly available in order to develop applications that benefit Canadians in their daily lives and to advance knowledge in areas that are important for our future. For example, Earth observation images beyond those produced by the RCM and data on atmospheric science, space weather and planetary exploration are available on the CSA's Open data page and through the Open Government portal.

Other space agencies like NASA and the European Space Agency operate various types of Earth observation satellites. In addition to Canada, radar satellites are also used by countries like Japan, Germany and Italy. Although they can work together to reach a common goal, like supplying images to support relief efforts as part of the International Charter "Space and Major Disasters," the satellites all have their own characteristics to meet national needs.

Each spacecraft functions independently. If one fails, the others continue to operate. We have a comprehensive contingency plan that details different scenarios in case any of these situations arise.

In the fall of 2023, the Government of Canada funded the CSA to initiate the design and construction of an RCM replacement satellite and to initiate the definition phase of a fourth-generation RADARSAT system.

Some repairs can be done through software patches. Any physical damages to the hardware of the spacecraft can't be repaired, but the critical components have redundancy systems that could be switched on if needed.

Canada is committed to the sustainable use of space and actively collaborates with other spacefaring nations on norms and guidelines to foster space sustainability, including post-mission disposal. The RCM satellites' operational health and fuel reserves are constantly monitored with the dual goals of being able to deliver their critical services and ensuring that the satellites can be securely de-orbited at the end of their mission.

The CSA's Collision Risk Assessment and Mitigation System (CRAMS) supports over 60 satellites, national and foreign, to assess risks of close approach or collisions and propose mitigation solutions. Three CSA staff members support CRAMS activities and also perform re-entry analysis activities when required. Objects larger than about 10 cm in size are currently routinely tracked by Space Surveillance Network sensors. When a possible collision is identified, satellite operators are notified, allowing a collision avoidance manoeuvre to be made when deemed necessary.