PARIS - Canada's Radarsat-2 Earth observation satellite, which has been almost a decade in design and construction, launched successfully Friday aboard a Russian Soyuz-Fregat rocket from Russia's Baikonur Cosmodrome in Kazakhstan, according to launch-services provider Starsem S.A. of France.

The 4,850-pound (2,200-kilogram) Radarsat-2 is expected to operate for seven years in a 495-mile (798-kilometer), sun-synchronous low Earth orbit and provide radar images with a ground resolution as sharp as 10 feet (three meters) and as wide as 328 feet (100 meters).

Despite being delayed by a host of technical and policy issues over the years, Radarsat-2 arrived in orbit in time to assure continuous radar Earth observation for Canadian authorities before Radarsat-1 is retired.

Radarsat-1, which provides images with a maximum sharpness of 10 meters, was launched in 1995 on what was designed as a five-year mission. It continues to operate today.

Radarsat-2 features an improved on-board memory and image-taking flexibility as well as a higher-resolution imaging mode. It is the product of a partnership between the Canadian Space Agency (CSA) and MacDonald, Dettwiler and Associates (MDA) of Richmond, British Columbia CSA has said its total Radarsat-2 budget is 421.6 million Canadian dollars ($419 million), and that MDA has spent an additional 90 million Canadian dollars on the satellite.

The launch of Radarsat-2 brings to a close an unusually busy year for radar Earth observation. German and Italian high-resolution radar satellites also began service this year, for both government and commercial customers.

MDA is Radarsat-2 prime contractor, with Thales Alenia Space of France and Italy providing the satellite platform. An MDA unit supplied the radar sensor.

The launch was managed by Starsem of Paris, a French-Russian joint venture that markets Soyuz rockets commercially.

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