Hayabusa veered off-course last Dec. 8, due to some unknown event that JAXA described as a "strong attitude disturbance." Officials said the newly restored communications with the probe remain at the relatively low speed of 32 bits per second � up from an initial speed of 8 bps. "The operation team will continue their efforts to have (Hayabusa) back to Earth by June 2010," the space agency said in a statement.

Last November, the spacecraft suffered a serious fuel leak immediately after it touched down for the second time on the surface of Itokawa, a small near-Earth asteroid. Officials said the leak has rendered the craft's main chemical engines unavailable, so when the December event occurred, JAXA was unable to correct Hayabusa's course.

On Jan. 23, controllers received an unmodulated radio signal during an uplink sweep that included a transmission of commands to the spacecraft. Because of the slow speed response speed, controllers said uplink commands did not go through easily at first, but by Jan. 26, Hayabusa began responding, revealing its status a little at a time until early February.

Based on the transmissions, JAXA discovered Hayabusa's spin axis attitude had shifted almost 90 degrees, which offset the axis of its high-gain antenna about 70 degrees from its proper orientation. Before the December event, the spacecraft's spin rate was direct and about 1 degree per second, but Hayabusa reported a retrograde spin of about 7 degrees per second.

After it received ground commands, Hayabusa has shifted its spin axis by about 2 degrees per day toward the Sun. On March 4, the antenna was within 14 degrees of proper orientation.

Hayabusa also reported it had lost power completely on one occasion after the spacecraft lost its attitude, and the Li-ion battery cells short-circuited � meaning the battery may not be operating. Although the chemical fuel is gone � the spacecraft reported zero pressure � controllers think the xenon gas needed to power the ion engines remains undisturbed.

JAXA controllers said they now estimate the chances of fully restoring communications with the spacecraft at 60 to 70 percent, because its attitude is now "well within the ground station's antenna beam width."

Controllers used range data obtained from Hayabusa, along with Doppler measurements, to determine its current orbit as about 13,000 kilometers (8,320 miles) ahead of Itokawa, and accelerating at about three meters (nine feet) per second. The craft lies about 190 million kilometers (121 million miles) from the Sun and 330 million kilometers (210 million miles) from Earth.

Based on Hayabusa's trajectory, JAXA controllers have devised the alternative flight plan to bring the spacecraft back to Earth in mid- 2010, three years behind the original schedule, assuming the three ion engines begin operating early next year. Officials said the plan remains under study.

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