Canada's Radarsat 1 satellite stopped communicating with Earth in late March, and officials fear the country's oldest Earth observation satellite may be lost for good, the Canadian Space Agency announced Tuesday.

Artist's concept of the Radarsat 1 satellite. Credit: Canadian Space Agency
 
Controllers last heard from the spacecraft March 29, when engineers noticed Radarsat 1 was in safe mode, a semi-dormant state in which the spacecraft conserves energy, according to Michel Doyon, flight operations manager at the Canadian Space Agency.

But soon after controllers noticed Radarsat 1 was in safe mode, the satellite went silent.

"We lost contact because it was out of battery power, and since then we've been trying various recovery procedures," Doyon said in an interview. "We have a team of experts looking at all aspects of this anomaly to try to find the root cause and potential remedial actions."

Officials have not given up reviving Radarsat 1, but the prospects are not promising.

"Make no mistake, this is a serious anomaly," Doyon said. "It is related to the power distribution system, so the chance of continuing a nominal mission is low, but we're still hoping to find a solution."

The satellite launched more than 17 years ago, surpassing its five-year design life and establishing Canada as a world leader in radar imaging from orbit. Doyon said Radarsat 1's performance was "remarkable" since launching in 1995.

"This situation does not impact the security of Canadian borders, coasts and northern territories as Radarsat 2 continues to provide critical, high-quality data," the Canadian Space Agency said in a statement. "Government and commercial users of Radarsat 1 have been advised that no new orders for imagery are being accepted, but that requests for archival images will continue to be processed."

Built by Ball Aerospace and Technologies Corp., Radarsat 1 is in a 500-mile-high sun-synchronous orbit covering the entire planet. Its C-band radar collected imagery of Earth's surface in day and night and in all weather conditions, creating images sharp enough to resolve objects as small as 8 meters, or 26 feet.

Radarsat 1's total cost was about $600 million, excluding launch costs, according to CSA.

Radarsat 1 data was used in maritime surveillance, cartography, ice research, oceanography, agriculture, forestry and disaster management applications.

A follow-on craft named Radarsat 2 launched in December 2007 and continues operating. Since its launch, Radarsat 1 took on a backup role to alleviate demand on the new satellite, Doyon said.

Radarsat 2 is designed to last until at least 2014.

Canada is developing a third-generation observation program called the Radarsat Constellation Mission, which features three satellites to gather imagery at a faster rate, covering Canadian territories at least once per day and up to four times daily in the Arctic.

The Canadian government signed a contract worth 706 million Canadian dollars, or $696 million, in January for MDA Corp. to construct the three next-generation Radarsat satellites. The satellites are scheduled for launch in 2018.