An unmanned Japanese spacecraft Sunday completed an unprecedented seven-year journey to the surface of an asteroid and back to Earth, officials said. The Japanese news service Kyodo reported the Japan Aerospace Exploration Agency said the space probe Hayabusa burned out before reaching the ground, but a heat-resistant capsule, possibly holding sand from the asteroid Itokawa, landed in the Australian desert near Woomera after separating from the probe shortly after 8 p.m. local time. Hayabusa, or falcon in English, launched in 2003, traveled about 4 billion miles on its trip from Earth to the asteroid and back, circling the sun five times, the United Press International (UPI) quoted Kyodo as reporting. Beset by technical problems, it completed its unprecedented trip three years behind schedule, Kyodo said. Kyodo said scientists could recover the 15.75-inch-diameter capsule as early as Monday. Researchers are hoping any materials returned from the asteroid might provide insight into the origin and evolution of the solar system, the news agency said. The only substances brought back to Earth from an astronomical body are rocks from the moon.