Tokyo ? A Japanese spacecraft on an unprecedented mission to bring asteroid material back to Earth was set to start home, an executive of Japan’s space agency, JAXA, said Sunday.

On Saturday, the Hayabusa probe apparently landed on the Itokawa asteroid and collected surface samples.

JAXA plans to re-ignite its engines by Dec. 10 for the return journey, JAXA executive Yasunori Matogawa said.

Otherwise it would be two more years before the probe would be in the right position to return, he said.

JAXA said the Hayabusa appeared to have touched down for a few seconds on the asteroid, collecting powder from its surface and then lifting off again to transmit data to mission controllers.

But the agency will not know for sure if Hayabusa collected surface samples until it returns to Earth. It is expected to land in June 2007 in Australia’s Outback.