posted November 21, 2005 09:52 AM            

"We made a first Touching Down (TD-1) attempt yesterday [Sunday].

Hayabusa released its 'Signature target Marker from 880,000 persons' at 40 m
and successfully changed its attitude control to 'terrain alignment
autonomous control using Laser Range Finder' at the altitude of just 17 m, below which Hayabusa itself stopped firing and started free fall descent to the surface. We were watching it via Doppler. But no touch-down occurred for surprisingly 30 minutes, during which the descent continued at very slow speed of about 2 cm/sec. We estimate
Hayabusa drifted at very low altitude along the surface. Therefore, Hayabusa did not touch down the surface, but reached
below 10 m altitude. In terms of the guidance and navigation as well as the 'Terrain Alignment Control', we think we achieved a big step.

We directed a command to Hayabusa to make an abort, since the sub-spacecraft point might have shifted so much from the intended area.
One concern was the surface temperature. The instruments temperature went high so much and we need to make sure if every instrument is still in order. This time, the guidance and navigation to the intended point was performed quite well with the residual speed of almost several mm/second.

Hayabusa fell into a Safe Mode at today's Touching-Down trial, due to some attitude anomaly very close to the altitude of about 10 m or so. The details are under investigation. The recovery operation has been performed successfully.

The project looks positively at the next opportunity, since almost every difficult step was now identified to function normally.

Jun Kawaguchi
Project Manager "

I've tidied up the email to make it read better in English but all the technical salient points are still in there

posted November 23, 2005 08:01 AM            

Here is a clip from email :-

"...Hayabusa is very far now from Itokawa and a bit concerned about whether
actually it returns back to the starting position in time....."

Phill Parker
spaceuk

posted November 23, 2005 11:56 AM               

I hope they are successful the second time and are able to return samples.

posted November 25, 2005 06:45 AM            

Several other spacecraft have,of course,bounced to a 'stop' on various planetary bodies during landing attempts including lunas, rangers, surveyors, Mars rovers, Veneras ..... :-)

Do we count Apollo lunar surface astronauts when they did their photo opportunity jumps eg John Young's jump :-))

Phill
spaceuk

posted November 25, 2005 06:57 AM            

I understand they will run the Hayabusa Live Blog again at www.jaxa.tv.

At about 1pm GMT Friday Hayabusa was 20 km altitude starting position.

[PS - A BBC News story has the time wrong - they were saying 700am GMT Friday)

posted November 25, 2005 10:59 AM            

As of 1:00 JST (Saturday morning in Japan,Friday night in UK), the distance between shape center of Itokawa and Hayabusa is approximately 1080 meters, and altitude is approximately 950 meters. Hayabusa is approaching Itokawa at a rate of three centimeters per second.

posted November 26, 2005 09:23 AM            

"The process of sampling also seems to have gone very well," said Jaxa's Kiyotaka Yashiro.

posted December 08, 2005 09:52 AM               

quote:

---

A Japanese spacecraft is likely to have failed in its landmark mission to collect the first-ever samples from an asteroid and also faces trouble returning to Earth, the space program said Wednesday.

The Japan Aerospace Exploration Agency had earlier said the Hayabusa probe "most probably" succeeded in gathering dust from the Itokawa asteroid, 290 million kilometers (180 million miles) from Earth, in late November.

"But now we found that the possibility is very high that a metal bullet to collect samples was actually not fired," said an official of the agency, which operates the probe.

---

posted December 09, 2005 05:44 AM            

an update from JAXA - including close images of the 880,000 name target marker on Itokawa.

Hayabusa is 550 km from Itokawa preparing for departure to earth - if still feasible with loss of thrusters.

posted December 10, 2005 01:17 PM            

However, they say Hayabusa is now leaving Itokawa The spacecraft has already left Itokawa and as of December 6th, the distance to Itokawa was about 550 km with the relative speed of about 5 km per hour.

The spacecraft was given a spin of about 1 degree per second.

At Dec 8th, communication with the spacecraft was established via medium gain antenna at the bit rate of 256 bps.

at the moment they are very unsure whether soil was actually collected at Itokawa by Hayabusa since on Dec 6th, a part of the data recorded by Hayabusa was reproduced and the pyro-controller data retrieved. It showed no ‘fire’ evidence about the pyro’s for the projectile initiation. However,In turn, there was NO ‘no-fire’ evidence, either !

At the same time, there was found an incorrectly positioned disarming command that may have been activated prior to the touching down. Pyros act with both arming and firing commands. The firing command was issued as reported before.

There was also glimpsed inconsistent phenomenon that may support the pyro initiation, such as the temperature increase.
However,detailed inspection of the sequence and command log is currently under way.

They also lost RCS fuel due to a leakage.
On Nov 26th, after the completion of the correction canceling the ascent speed, the RCS thrusters were switched to the subsystem-B, but there was a leak from one thruster on the upper panel of the spacecraft belonging to subsystem-B. Shutting off the latching valves for both the two subsystems was commanded and it worked. But some acceleration due to the leak was observed.

Due to the leakage ,orientation of the spacecraft was lost for a while and solar power dropped severely. Because of this, the
onboard batteries were almost drained.

However,I understand orientation has been regained and , hopefully,power will be built up over a period of time?

They have since tried to use the RCS jets but thgis failed since they believe that they may have frozen after the command to shutoff both systems? So, instead, they believe they have enough Xe-gas onboard for the ion engine to return Haybusa to Earth and for attitude control during the remaining mission. But, they still work at perhaps getting the RCS jets back - though fuel is assumed to be now very low since the leak. However, they assume the ion engine is working fine at the moment but they are still checking this out and will be around 10 days for them to do this.

Communications by the ground station with with Hayabusa is through the spacecraft's medium gain antenna, at the bit rate of 256 bps.

Phill Parker
spaceuk

posted March 08, 2006 10:07 PM               

More information can be found at this link:
http://www.spacedaily.com/reports/JAXA_Reconnects_With_Hayabusa_Probe.html