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View Full Version : Hayabusa Update - October 4, 2005


October 5th 05, 02:23 AM
http://www.isas.ac.jp/e/snews/2005/1004.shtml

Current Status of Hayabusa Spacecraft
Japan Aerospace Exploration Agency (JAXA)
October 4, 2005

Excerpts:

o On September 30th, Hayabusa descended to the distance of 6.8 km,
Home Position, and entered into a new flight phase.

o On that day, Hayabusa fired its RCS engines about 5cm/second to
raise the altitude again to keep its relative position within
a certain control box.

o Hayabusa will make higher latitude imaging as well as inspection of
touching-down candidate points for a month.

o Every scientific instrument functions normally.

Current status of Spacecraft

o As already reported, Hayabusa lost one reaction wheel (X-axis) on
July 31st and has taken an alternate flight mode using two wheels
for attitude stabilization.

o On October 3rd, another Y-axis reaction wheel was found not
functioning. The incident occurred at 23:08 JST on Oct. 2nd,
while it is not operated from Japan.

On the malfunction of Y-axis wheel

o When the incident occurred, Hayabusa was under the autonomous
asteroid tracking mode. The task was with no trouble compensated
by RCS (chemical engines) and the observation has been maintained.

o Currently, Hayabusa continues the attitude stabilization using
one wheel plus two RCS engines. And subsequent observation plan is
studied after adequate amount of information is gathered.

o Note, Z-axis wheel has not problem from launch and in good health.

Affect to Further Hayabusa Flight Activity

o Still under detailed study

o Fortunately, global mapping is almost completed.

o In terms of guidance and navigation, Hayabusa uses radio
measurements,
and no problem is foreseen.

o Operation team is analyzing how to reduce fuel comsumption for
attitude
stabilization.

o Activity plan will be updated and reported, as soon as the strategy
is
fixed.

Flight Schedule Ahead

o In the middle of October, high latitude observation and landing
site
inspection are planned

o In November, a rehearsal and two touching-down samplings are
performed.

o At the beginnig of December, Hayabusa departs for Earth, returning
samples of Itokawa in June of 2007.