Chang'e-4 farside landing mission Options

[John Moore]

Interesting, those spherules...gives us an idea of how the cameras can pick up such small detail, as well as geological dynamics (impact occurrences etc.,).

John Moore

[Phil Stooke]

https://moon.bao.ac.cn/web/zhmanager/notice...detailId=864008


"The 24th batch of scientific data released by Chang'e-4
Release time: 2022-03-03 Views: 24

On March 3 , 2022 , the Lunar Exploration Engineering Ground Application System publicly released the twenty -fourth batch of scientific data from Chang'e- 4 . The Chang'e-4 probe successfully landed on the far side of the moon on January 3, 2019, Beijing time, achieving the world's first soft landing and inspection survey on the far side of the moon. By the end of February 2022 , the Chang'e -4 lander and the Yutu-2 lunar rover had completed the scientific exploration of the thirtyninth lunar day and had travelled 1,029 meters."

(I edited that a bit for clarity)

1029 m total means 25 m during that lunar day. The path I had estimated on my latest map probably has roughly the right shape but needs to be shrunk to fit that distance. I will correct it later.

Phil

[Phil Stooke]

We are in the final few days of Yutu 2's lunar day 41. Still no word yet on activities during lunar day 40 but I am hoping for a drive diary.

Phil

[Phil Stooke]

https://twitter.com/AJ_FI/status/1513513237345615875

Andrew Jones tweets a total cumulative distance for the end of lunar day 40: 1065.5 m. That means about 37 m that lunar day. No other news yet. We are at the end of day 41 and could expect a total distance now of about 1100 m.

Phil

[Phil Stooke]

https://news.mydrivers.com/1/826/826332.htm

This article (in Chinese) gives a route map up to the end of day 41 (I have to try very hard not to write Sol 41) and a drive distance of 1112 m, meaning 46 m in lunar day 41. The map is small and not very clear. I will look for a better version of it.

EDIT: Curiously, this site:

http://www.chinanews.com.cn/sh/2022/04-15/9729471.shtml

gives a distance of 1142 m, which seems too large. I'm seeing that distance in several places. I will try to figure out what is going on.

Phil

[Phil Stooke]

The distance of 1142 m is repeated in many places, suggesting it is correct, but I am having a bit of trouble reconciling reported distances.

Here:

https://finance.sina.com.cn/tech/2022-04-27...st4316724.shtml

is a new drive diary describing recent activities, especially the approach to a rock called Dragon's Back. From images and descriptions I will be updating my map - the end of day position was not at the south end of the path as I showed it before because the rover returned to its local noon position.

Phil

[Phil Stooke]

An interesting tweet by Andrew Jones:

https://twitter.com/AJ_FI/status/1521102822971953152

It says Yutu 2 has now driven 1181 m.

The last report was 1142 m at the end of day 41. That in itself implied a drive during day 41 of about 76 m, equal to the record set in lunar day 2. Now we have another 39 m driven in day 42, but we are currently in the local noon 'siesta' with the afternoon drives still to come. 39 m would have been a very respectable distance for an entire lunar day for most of the mission. It suggests the pace of driving is really picking up. A report from when they were approaching the 'mystery hut' said they had increased distance by taking stereo images for planning at a higher elevation angle, extending their topo map for each planning cycle, and also by shortening the noon break period, adding 2 days of potential driving.

If I am misinterpreting this please let me know.

Phil

[climber]

An interesting tweet by Andrew Jones:

https://twitter.com/AJ_FI/status/1521102822971953152

It says Yutu 2 has now driven 1181 m.

The last report was 1142 m at the end of day 41. That in itself implied a drive during day 41 of about 76 m, equal to the record set in lunar day 2. Now we have another 39 m driven in day 42, but we are currently in the local noon 'siesta' with the afternoon drives still to come. 39 m would have been a very respectable distance for an entire lunar day for most of the mission. It suggests the pace of driving is really picking up. A report from when they were approaching the 'mystery hut' said they had increased distance by taking stereo images for planning at a higher elevation angle, extending their topo map for each planning cycle, and also by shortening the noon break period, adding 2 days of potential driving.

If I am misinterpreting this please let me know.

Phil

We’re about 1225 terrestrials days since landing so very close to 1 m/day. Just saying

[Phil Stooke]

Looking up at the Moon, high in the sky this afternoon at First Quarter phase - a sign that the Sun is setting over Von Karman crater on the far side. The end of day 42.

Phil

[Phil Stooke]

If you are trying to keep up with Yutu 2, well, so am I. It's not easy at the moment. We are nearing the end of lunar day 43 and still no real news about day 42 that I have seen. The last news I have is from here:

https://moon.bao.ac.cn/web/zhmanager/notice...detailId=874620

"As of the end of April 2022 , the Chang'e-4 lander and the Yutu-2 lunar rover have completed the scientific exploration of the 41st lunar day , and the lunar rover's cumulative mileage has reached 1,181 meters."

But that seems to be the distance at mid-day on day 42, the end of April, not the distance at the end of day 41. As I say, it's not easy.

Phil

[Phil Stooke]

Two days later... another update from the same source:

https://moon.bao.ac.cn/web/zhmanager/notice...detailId=885442

But it only adds to the uncertainty. Now it says (via machine translation):

"As of the end of May 2022 , the Chang'e-4 lander and the Yutu-2 lunar rover have completed the scientific exploration of the 42nd lunar day, and the lunar rover's cumulative mileage has reached 1,171.8 meters."

Was it driving backwards? No, there's a mistake somewhere but I have no idea where it is. I am more inclined to believe this new figure, as the previous one implied some unexpectedly large drives.

Phil

[Phil Stooke]

It's past midnight on the 43rd night and no news yet on day 43, but here is a drive diary for day 42:

https://www.toutiao.com/article/71075842400...d=1655449348340

(in Chinese).

I can use it for a map update which will follow soon.

Phil

[Phil Stooke]

The sun will rise on Yutu 2 in a few hours... rover operations start a day or so later, on the 44th lunar day. No word yet on activities during day 43.

Phil

[Phil Stooke]

End of day 44 and Andrew Jones tweets some details:

https://twitter.com/AJ_FI/status/1544703692833755137

The distance is almost 1240 m and a drive map is released. I will update my map but there is some uncertainty. If the map shows the location at the end of day 44, where was the end of day 43? On my map the 42nd night location comes from a detailed map in the latest drive diary. This new map shows less than 50 m driving since then which doesn't seem to match the total drive distance very well. I suspect the new map shows the location at the start of day 44 (i.e. the 43rd night location), not the end of day 44. The next drive diary, if we get one, may clarify the situation.

Phil

[Phil Stooke]

This link:

https://www.cjss.ac.cn/en/article/doi/10.11...jss2022.04.yg30

is to an open access paper in English on 3 years of the Chang'e 4 mission.

Phil