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Unmanned Spaceflight.com > Earth & Moon > Lunar Exploration > Chang'e program
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Hungry4info
The China Space facebook page reports the lander has awaken (Link).
I haven't heard anything about the rover.
marsbug
I've no news I'm afraid, but I do have a question: The lander itself has instruments for UV astronomy and plasmasphere investigations. If Yutu has gone to the land of eternal crunchy lettuce, how long will the lander mission continue to run without the rover?
Phil Stooke
The lander was intended to last for a year. It doesn't need the rover - and the rover doesn't need the lander, it could be completely independent as they hoped it could travel several km away from the lander.

Phil

marsbug
Thanks Phil. It's good to know the lander is designed to run for a year. I was as much wondering if the Chinese space agency would consider the lander investigations worth the effort and money of running on their own, or if they were just a sideshow to the rover that would be kept going as part of the overall budget of rover/lander mission, but not as just a lander. Paranoia, perhaps, but sometimes these things are politically influenced and the reasons why experiments are turned off aren't always clear.

I'm going to have to uncross some things for Yutu, I'm starting to ache.....

[MOD NOTE: Let's be careful about rule 1.2 here.]
A.Nemo
QUOTE (marsbug @ Feb 11 2014, 10:07 PM) *
I've no news I'm afraid, but I do have a question: The lander itself has instruments for UV astronomy and plasmasphere investigations. If Yutu has gone to the land of eternal crunchy lettuce, how long will the lander mission continue to run without the rover?


CE-3 Lander will run one year , while china engineers had thought extended to two year
Phil Stooke
http://news.sohu.com/20140211/n394783771.shtml

The little video on this site doesn't tell me much but it does include some glimpses of images we have not seen before - rocks near the lander with a lower sun angle.

I have also seen a statement that there will be a news release tomorrow.

Phil
Hungry4info
Loss of lunar rover
QUOTE
China's first lunar rover, Yutu, could not be restored to full function on Monday as expected
marsbug
Mods: Understood.
Rest well little rabbit, may your memory be honoured by many successors.
Cosmic Penguin
QUOTE (Hungry4info @ Feb 12 2014, 06:59 PM) *


Doesn't sounds like a convincing source. I think that unless Xinhua News et al. release something, we probably can't be sure that it's gone. And all the official sources are still silent (even for the lander!)....... huh.gif
Cosmic Penguin
QUOTE (Cosmic Penguin @ Feb 12 2014, 09:24 PM) *
Doesn't sounds like a convincing source. I think that unless Xinhua News et al. release something, we probably can't be sure that it's gone. And all the official sources are still silent (even for the lander!)....... huh.gif


And just after I wrote that there's this news claiming that the rover is showing "signs of activity" - with Xinhua News shown as the source! So maybe it's not dead? rolleyes.gif (remember that we don't even know what happened to it!)
Yeh
From Xinhua this morning: "Bunny seems getting better, there is evidence that he is awake, we will see." But no further details are disclosed.

http://news.sina.com.cn/c/2014-02-12/21222....shtml?wbf=more (in Chinese)
A.Nemo
Official Xinhuanet have gave us some good news:
http://t.qq.com/p/t/385354002655232
http://t.qq.com/p/t/362386008552526
一位正在抢救小兔子的嫦娥三号任务核心人员刚才用嘶哑的声音、兴奋的语调告诉记者:小兔子情况趋好,有点再醒的迹象,再等等。这是自上月25日玉兔进入月夜以来记者第一次听到积极消息。小兔子,加油!师傅们,你们辛苦了!记者余晓洁

turns well, a signs of Yutus activity,Yutu begin awake?
It's first good news last from January 25,Please wait for a while
ustrax
"Official news: Yutu is still alive! Mission control is busy working on it. Please give more time." smile.gif
https://www.facebook.com/photo.php?fbid=675...e=1&theater
Yeh
From my understanding of CNSA's habit, this (a very brief Xinhua news; CNSA remains silent) may mean that they got another 14 days trying to deal with the mechanical breakdown.

If they have fixed it, I don't see a reason for them to hold the news...

But anyway, the reconnection is good and encouraging. At least there are chances to solve the problem.
marsbug
Hurrah! Let us hope Yutu has made it through the night without too much damage. Good luck to the mission control team.
mcaplinger
Maybe all those ham radio operators who are complaining about the ISEE-3 situation should try listening for downlink from Yutu instead. rolleyes.gif
Paolo
signal from Yutu!
http://pjm.uhf-satcom.com/twtr/yutu_8462077.jpg
Thorsten Denk
Great! biggrin.gif

One question, for people (like me) who are not experts
for electronics hardware at low temperatures:
What is the problem with the low temperatures?
What exactly happens, how is the electronics knocked out?
Thanks for the answers.

Thorsten
mcaplinger
QUOTE (Thorsten Denk @ Feb 12 2014, 02:05 PM) *
What is the problem with the low temperatures?

Thermal expansion/contraction can break solder joints, internal bond wires, etc.
Some components (e.g., electrolytic capacitors, batteries) have goop that can freeze.

In general it's not that hard to build something that can survive Mars surface temps, but it gets colder and hotter on the Moon, so more stress.
djellison
QUOTE (mcaplinger @ Feb 12 2014, 12:30 PM) *
Maybe all those ham radio operators who are complaining about the ISEE-3 situation should try listening for downlink from Yutu instead. rolleyes.gif


They did. With success :-O

Yup - I was surprised as well.

https://twitter.com/uhf_satcom/status/433709448717033472
mcaplinger
QUOTE (djellison @ Feb 12 2014, 03:47 PM) *
They did. With success :-O

Detecting a signal is a good deal easier than decoding it, much less generating an uplink, of course.
Yeh
CNSA confirmation:

http://www.weibo.com/1488228740/Awubn3MXf

官方消息:探月工程新闻发言人裴照宇昨晚表示,国产玉兔号月球车已全面苏醒,状态趋于好转,但是出现问题的机构仍然有待进一步恢复。只有苏醒了才有排故的时间,希望得到很好的救治和疗养,兔子好好休个假。

CLEP news officer Pei Zhaoyu said the Yutu rover is fully awaken and is getting better, but the mechanical problems are yet to be solved.

UPDATE: CAS official microblogger says the same thing: http://www.weibo.com/3494982177/AwufW7cDi . There is an updated news brief from Xinhua there, but says nothing relevant to the exact problem.
Hungry4info
From Xinhua.
China's lunar rover "awakes" despite abnormality: spokesman
"The rover stands a chance of being saved now that it is still alive,"
elakdawalla
This came to the Lunar Listserv from Yong-Chun Zheng:
QUOTE
Yesterday night, the Jade Rabbit lunar rover have sent us a good message from the Moon. In the last lunar day for the landing site, the rover met trouble to move on the surface. The control structure of the rover can't function as designed. The rabbit has gone into sleep without protection. Fortunately, our rabbit awakes yesterday with the efforts of the engineers. The instruments on the rover stood up to the challenge of the very low temperature in the lunar night. The rover can recieve the command from the ground station. We have also recieved the the data from the rover. Except some sensitive components, most of the functions of the rover have been recovered. Its experience can contribute much for all future lunar mission, both lander or rover.The lunar and planetary missions are not easy for any country. They always give us joy mingled with surprise. We anticipate the brave Jade Rabbit get new discovery on the Moon. Cheers.
Explorer1
It might be possible to make a visual diagnosis of the panel hinges or whatever the jammed part is, given that the lander is operational and still nearby? It all hinges on whether Yutu can drive or not, but it would take out a lot of guesswork on figuring out the issue (Galileo's high gain antenna comes to mind).
elakdawalla
Remember that the lander's main camera no longer works -- it failed (as expected) after the first night.
Explorer1
Yeah, I heard about the topography camera failure, but we know there were three others on the sides, given those great perspectives on landing day.
I was just thinking of all those other missions with mysterious failures that could have been solved or at least diagnosed by a nearby pair of eyes (or hands with a nice wrench/brush/lubricant)!

A.Nemo
QUOTE (Paolo @ Feb 13 2014, 02:27 PM) *
this image from one of the TV reports has been posted on a French forum
http://www.servimg.com/image_preview.php?i...&u=17604920
I think we have never seen it before, and it looks like a perspective from late on the first lunar day

EDIT: I post the image below because I don't trust these image hosting sites...


Yutu Awake, CCTV have reported:
http://news.cntv.cn/2014/02/13/VIDE1392290645405335.shtml

Chang'e-3 have Awaked, too
Thorsten Denk
Two days from now, on Sunday 23 at 22:20 UT,
will be the third sunset for the two spacecraft.

News from Yt have gone down to zero.
Are there maybe some chinese natives who know more?
If so, please let us know! Thank's a lot! Xixie!

Thorsten
Paolo
there was a release in Chinese 2 days ago http://www.chinanews.com/mil/2014/02-19/5856563.shtml
troubleshooting continues. no more details given
Cosmic Penguin
Whatever it is, it looks like the "problem" is wheel/bogie related, as it turns out that Yutu was almost fully operational on the third lunar day (which it didn't move for the whole period), with the PanCam, VIRS and GPM working (I assume that the APXS is too, just that ground controllers aren't bothered with pulling its arm out): http://www.chinanews.com/mil/2014/02-23/5870836.shtml

And of course the lander's LUT and EUV imager were working as well for the whole lunar day. The lander went into hibernation for the 3rd lunar night yesterday, with the lander following several hours ago.

Here's a (new?) photo by the PanCam of the rover:
kenny
I think that is indeed a 'new' photo, taken from a position South-west of the lander. My guess is it is taken from fairly close to the lander, from a position not shown on Phil's map -- in other words,
after coming round the lander Yutu perhaps made an excursion westwards which has not been noticed or recorded so far.

An alternative explanation for that view might be that it was taken in zoom mode from the 11-14 January position or later. However, I think that less plausible because of the clear view it shows of the
turning tracks made after deployment - those would be surely more foreshortened if seen in zoom from a distance.

Edit: one further thought... the shadows of the 2 deployment ramps in the 'new' photo are cast directly below the ramps, showing the sun was due south and therefore it was local midday.
The earlier post deployment photos of Chang'e from Yutu were taken well after midday, as the link below shows. Hence, the 'new' picture was perhaps taken on Day 2.

Chang'e from the south, Day 1
dilo
QUOTE (Cosmic Penguin @ Feb 23 2014, 05:17 AM) *
Here's a (new?) photo by the PanCam of the rover:

In this site the pictures are two, from left and right mastcam:
http://news.xinhuanet.com/english/photo/20...133136783_2.htm
Here below the crossed eye version:
Click to view attachment
kenny
So this status report alongside the picture, implies that Yutu could even have taken the 'new' photo on Day 3....

" This undated photo taken by the camera on the Yutu moon rover shows the Chang'e-3 moon lander and the moon surface. The Chang'e-3 lander entered its third dormancy on early Feb. 23, 2014. China's
lunar rover Yutu also entered the dormancy on Feb. 22, with the mechanical control issues that might cripple the vehicle still unresolved. According to the State Administration of Science, Technology
and Industry for National Defence (SASTIND), Yutu only carried out fixed point observations during its third lunar day, equivalent to about two weeks on Earth.
Yutu's radar, panorama camera and infrared imaging equipment are functioning normally, the control issues that have troubled the rover since January persist. (Xinhua/SASTIND) "

And the parallax on those 2 left/right photos shows they were definitely taken close the lander from the SW, at a new position.
Explorer1
Ah, so they did move back towards the lander after all. Whether the remaining B/W cameras can make out a visible fault is the multimillion yuan question...
Hungry4info
http://www.moondaily.com/reports/Is_Yutu_Stuck_999.html
http://www.spacedaily.com/reports/No_Call_for_Yutu_999.html

Some updates, with more elabouration on the technical state of the rover.
Cosmic Penguin
The "problem" with the rover has finally been reported: some sort of electrical problem with the motor-driving circuit board. That's still unresolved as of right now so some luck is needed again for the rover to wake up on the next lunar sunrise.

Source
Paolo
I can't see how a motor-driving board can put at risk the night hibernation. unless of course it also controls the retractable solar panels
Cosmic Penguin
QUOTE (Paolo @ Mar 1 2014, 02:56 PM) *
I can't see how a motor-driving board can put at risk the night hibernation. unless of course it also controls the retractable solar panels


It seems that's exactly what Ye Peijian implying...
Paolo
yep, there is now also an English release where it is stated:

QUOTE
"Normal dormancy needs Yutu to fold its mast and solar panels," said Ye. "The driving unit malfunction prevented Yutu to do those actions."
Phil Stooke
If they can't fold one panel over the warm box, they probably can't tilt the other one down to face the rising sun (so it has to rise higher to shine on the panel and generate power). If they can't drive they may not be oriented to face that panel towards the rising sun, causing further delay.

Phil

William Pei
Chang'E 4 will launch this year, Ye Peijian also said: Chang'E 4 will landing a more challengeable place on the moon or even not the moon. So we may have two rabbit on the moon or another rabbit on some asteroid?
kenny
In that case, we may need a new thread for Chang'e 4, as we already have 5 covered.

A landing on anywhere other than the moon is a whole different game requiring extensive mission re-design.
Phil Stooke
I had the impression that a non-lunar option had been considered at some point in the past, but personally I would expect that the desire to demonstrate a fix for YuTu's problem would be most important now, as well as a wish to drive a much greater distance.

Phil

Cosmic Penguin
QUOTE (William Pei @ Mar 4 2014, 05:53 PM) *
Chang'E 4 will launch this year, Ye Peijian also said: Chang'E 4 will landing a more challengeable place on the moon or even not the moon. So we may have two rabbit on the moon or another rabbit on some asteroid?


Are you sure? I saw 2016 mentioned elsewhere on the Chinese side.......

Phil Stooke
This is the new image of tracks showing my interpretation, and an alternative.

The image is a composite of two, the upper left and lower right panels of the 4-panel image put on the LROC site. The pre-landing image is used to partially subtract topography - only partially as the lighting is different. I want to emphasize tracks.

In the right half I overlay red lines: the tracks as I mapped them in the map thread, and blue lines: another possible interpretation.

Phil

Click to view attachment
William Pei
QUOTE (Cosmic Penguin @ Mar 5 2014, 02:14 AM) *
Are you sure? I saw 2016 mentioned elsewhere on the Chinese side.......


As a backup spaceship, Chang'E 2 was launched at next year of Chang'E 1, so Chang'E 4 will most possibly to launch at 2014, but this is depend on the progress of Longmarch-5 rocket and Wenchang space center, if Chang'E 4 decide launch at there, may be delay to 2015, but no more late than that time, because Chang'E 5 will launch at 2017 by an officilal statement.
Thorsten Denk
Next Sunrise in 4 hours.
Will there be again a sign of life from Yt? sad.gif
(In two days or so of course!)

Thorsten
Yeh
News this morning: http://news.sina.com.cn/c/2014-03-11/033929674756.shtml (in Chinese)

Ye Peijian mentioned that a "test probe" for Chang'E 5 will be launched late this year. The probe "will not land on the Moon or take samples", "simply travel to the Moon and come back". But he did not indicate this will be Chang'E 4 or just as a separate test mission.
Explorer1
Sounds like a free return trajectory. Or perhaps braking into orbit and then escaping again for the challenge?
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