A Japanese research probe failed to touch down on an asteroid Sunday after maneuvering within meters (yards) to collect surface samples, Japan's space agency said.
The Hayabusa probe, which botched a rehearsal earlier this month, was on a mission to briefly land on the asteroid, collect material, then bring it back to Earth.
When Hayabusa was 40 meters (130 feet) above the asteroid Itokawa, it dropped a small object as a touchdown target, then descended to 17 meters (56 feet), said officials from Japan's space agency, JAXA.
At that point, ground control lost contact with the probe for about three hours, the officials said.
"Hayabusa reached extremely close, but could not make the landing," said JAXA spokesman Toshihisa Horiguchi, adding that the reason for the failure was unknown.
The probe switched to auto-control, storing data about itself and later transmitting it to ground control to be analyzed.
The exact location of the probe was unknown, Horiguchi said, but it was believed to be within 10-100 kilometers (6-60 miles) of the asteroid. Officials plan to make a second landing attempt on Friday.
The mission has been troubled by a series of glitches.
A rehearsal was aborted earlier this month when it had trouble finding a landing spot, and a small robotic lander deployed from the probe was lost. Hayabusa also suffered a problem with one of its three gyroscopes, but it has since been repaired.
Hayabusa was launched in May 2003 and has until early December before it must leave orbit and begin its 290 million-kilometer (180 million-mile) journey home. It is expected to return to Earth and land in the Australian Outback in June 2007.
The asteroid is named after Hideo Itokawa, the father of rocket science in Japan, and is orbiting the sun between Earth and Mars. It is 690 meters (2,300 feet) long and 300 meters (1,000 feet) wide and has a gravitational pull of only 1/100,000th of Earth's, which makes landing a probe there difficult.
Japan was the fourth country to launch a satellite, in 1972, and announced earlier this year a major project to send its first astronauts into space and set up a base on the moon by 2025.
Examining asteroid samples is expected to help unlock secrets of how celestial bodies were formed because their surfaces are believed to have remained relatively unchanged over the eons, unlike those of larger bodies such the planets or moons, JAXA said.
A NASA probe collected data for two weeks from the Manhattan-sized asteroid Eros in 2001, but did not return with samples, AP reported. V.A.