The spokesman said that these echoes "are not images with a definition like a photograph, but they do allow us to identify the nature of an object and to localize it."
Gathering satellite echo data involves sending a beam of energy to the Earth and then analyzing it when it bounces back, according to Joseph Bermudez Jr., chief analytics officer at AllSource Analysis, a commercial satellite intelligence firm.
Satellite radar echoes can be converted into an image that would look similar to a black-and-white photo, though not as clear, he said. "You'd have to know what you're looking at," Bermudez said.
A Malaysian official involved in the search said the French data located objects about 930 kilometers (575 miles) north of the spots where the objects in the images released by Australia and China were located.
One of the objects located was estimated to be about the same size as an object captured Tuesday by the Chinese satellite that appeared to be 22 meters (72 feet) by 13 meters (43 feet), said the official, who declined to be identified because he wasn't authorized to speak to the media.
US underwater wreck hunter David Mearns on Monday described the French satellite sighting of potential debris as a "positive development," although he was unaware of the full details.
Mearns was an adviser to British and French search authorities following the loss of Air France Flight 447 in the Atlantic Ocean during a flight from Brazil to Paris in 2009.
He warned that time was running out to find confirmed wreckage that could lead searchers back to the aircraft's black box.
