Japan Aerospace Exploration Agency (JAXA)
Hayabusa that arrived at the target asteroid Itokawa on September 12th of this year has performed detailed scientific observation so far by varying its relative position around Itokawa.
As already reported, Hayabusa carried two reaction wheels were lost on July 31st and October 3rd, and its attitude has been maintained by a single wheel together with the chemical engines aboard, while the spacecraft has been operated normally.
In order that the flight can be carried out and completed until the return to the Earth, the fuel consumption required for stabilizing the attitude has to be reduced, and a strenuous effort has been poured to devise the strategy including a number of firing tests in vacuum on the ground. A new control scheme making the firing impulse enough small has now been developed assuring the attitude control resolution to be well managed. This assures the fuel amount required is adequate within that remains. The on-orbit function test was already conducted and it was verified functioning by the actual flight hardware and software aboard. The Hayabusa project team concluded the flight operation until the return to the Earth is feasibly performed, as long as the existing instruments and hardware aboard continue working normally as they are.
JAXA Public Affairs Department
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