Posted on 10/05/2005 6:20:48 PM PDT by snowsislander
PARIS — Japan’s Hayabusa asteroid sample-return spacecraft has lost the use of a second reaction wheel, forcing increased reliance on its chemical-propellant thrusters for attitude control and raising questions about whether it can make its planned asteroid touchdown in November, Japan’s Institute of Space and Astronautical Science (ISAS) announced Oct. 4.
Hayabusa, known as MUSES-C before its May 2003 launch, remains in a stable position 6.8 kilometers from its target, the Itokawa asteroid, now 305.9 million kilometers from Earth. Using two reaction control systems with the remaining reaction wheel, the probe is scheduled to continue scouting possible landing sites on Itokawa in the coming weeks.
ISAS said part of the mission — to take high-resolution pictures of the asteroid — almost is completed. The mission also has validated the performance of the on-board optical navigation camera, according to ISAS.
Hayabusa ground controllers must now alter their mission profile to conserve fuel burned by the unanticipated use of the reaction control system. The first reaction wheel failed in July. The most recent failure occurred late Oct. 2 Japan Standard Time.
If the original mission scenario is maintained, Hayabusa in November will perform what ISAS calls “touch and go” maneuvers — briefly landing on the asteroid, scooping up small samples and then taking off — before beginning its return voyage to Earth, with the samples, in December. Its arrival is scheduled for June 2007.
The name is 'Hayabusa'? Someone should tell them you can't ride a motorcycle into space.
Sounds like a pretty amitious mission.
Yes, I think it is an impressively ambitious mission. They are trying a host of new technology: microwave ion propulsion, the touch-and-go's under autonomous systems, attempting a return to drop off the samples, and there was the even the possibility of further missions, though I wonder with this latest problem (Hayabusa also was very negatively affected by the huge bursts of solar activity in the last few yeras) if those are still on the table.
I think " Itokawa" is Japanese for "shaped like a turd". Have you seen picture of that thing? Is it pronounced "I tooka one"? Sounds like Engrish.
JAXA reignited the ion engine of the Asteroid Explore "HAYABUSA" for a powered flight at 11:35 a.m. on February 4, 2009 (JST.) The HAYABUSA arrived at the asteroid "ITOKAWA" in 2005 and is now scheduled to return to the Earth in June 2010.We will continue to gradually accelerate the HAYABUSA by the ion engine until around March 2010 to carry out the second phase orbit maneuvering for returning it to the Earth.
February 4, 2009
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