This is a VERY interesting, innovative, and extremely capable little lander with maximum value in minimum volume and mass (merely 120 kg dry!). MANY fascinating features and creative methods used. Includes two clever mini-rovers using new techniques. This one is much more interesting than any recent lunar lander I've seen details about. A SUPER shame it has had difficulties - solar cells not charging the battery.

An excellent overview of the lander hardware and tech in the video below. I wish the YouTuber had STFU during the landing phase shown here since the English audio translated JAXA version which was shown live and which has, for now at least, been overwritten by their press conference, was more informative:

https://www.youtube.com/live/Bg67FA...re=shared&t=728

The provided, live telemetry screen was excellent.

Lots of almost good enough questions to the post landing panel, some typically stupid ones (paraphrasing: "What was the mood in the control room?" My sarcastic answer, "What would you reasonably expect it to be?") but, hearing the answers to the halfway good ones, these would be mine:

"I assume that the attitude sensors which allowed you to land can also tell you whether the lander is properly upright. Is it? If it is, considering that the solar cells are on the top of the vehicle, it should be generating electricity which would indicate a harware problem. What is the angle of elevation of the sun over the lunar horizon and, if low, could the lander be in a shadow? If it is, in fact, in a proper upright position, which I have not heard you specifically claim, would this possibly be the reason you mention some hope of battery charge resulting from a changing sun position over the next 30 days. If it is not properly upright, the same hope would be valid."

Apparently, for some strange reason, they apparently don't know that it landed in the proper attitude because, finally, after a bazillion questions, someone asked that if the lander isn't upright and the solar cells are pointed in a bad direction that a charge could come from the changing position of the sun and the main JAXA panel member just nodded. I noted that after landing, the telemetry screen model of the lander was at a weird angle. Also, couldn't they tell if the lander isn't at the proper attitude because of the effect that would have on the comm link receive signal level?

Finally, one panel member finally said that "once the (lander) angle is received." What?!

Another decent question was from someone who, like me, was watching the excellent live telemetry display that had an animated lander model who got the impression that the last few meters of descent seemed too fast. Amazingly, none on the panel could answer that as they had no data on the landing velocity! NOT enough important questions answered by that panel.

The lander was designed to survive the two week long lunar night and they claim that the mission isn't necessarily over when the battery dies, I assume due to the sun position change possibly charging the battery.

__________________
The other day I sat next to a woman who has a profound fear of flying. I wanted to comfort her, so I said, "Don't worry, we're not gonna' crash. Statistically, we got a better chance of being bitten by a shark." Then I showed her the scar on my elbow from a shark attack. I said, "I got this when my plane went down off of Florida." - Dennis Regan

Japan Lands On The Moon.... Upside Down? Astrobotic's Moon Lander Lands On Earth?

https://www.youtube.com/watch?v=muK6gFtv7_o

__________________
The other day I sat next to a woman who has a profound fear of flying. I wanted to comfort her, so I said, "Don't worry, we're not gonna' crash. Statistically, we got a better chance of being bitten by a shark." Then I showed her the scar on my elbow from a shark attack. I said, "I got this when my plane went down off of Florida." - Dennis Regan

Thanks for that. As always, a good watch from Scott Manley.

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Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

So it may have come in hot and took an unfortunate bounce?


Bill

__________________
It is well past time to Drill, Baby, Drill!

If your June, July, August and September was like this, you might just hate summer too...

Please unload your question before you ask it unless you have a concealed harry permit.

: countdown begin cr dup . 1- ?dup 0= until cr ." Launch!" cr ;

Give a man a rocket and he will fly for a day; teach him to build and he will spend the rest of his days sanding...

A PRANG would have been funny

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !

SLIM's mini-rovers luckily don't rely on the lander. They were released just prior to the landing.

__________________
The other day I sat next to a woman who has a profound fear of flying. I wanted to comfort her, so I said, "Don't worry, we're not gonna' crash. Statistically, we got a better chance of being bitten by a shark." Then I showed her the scar on my elbow from a shark attack. I said, "I got this when my plane went down off of Florida." - Dennis Regan

The phases of lunar lander success
January 22, 2024

https://www.thespacereview.com/article/4729/1

Excerpt:

JAXA's webcast of the landing showed a telemetry screen rich in detail about the vehicle's position during its terminal descent, including performance of its thrusters and remaining propellant supplies. The lander appeared to be following its intended path as it swooped up slightly before descending the final few kilometers to the surface, hovering 50 meters above the surface as planned to select a landing site before heading to the surface.

The landing itself was strangely anticlimactic. "Now you see on the left-hand side 'MLM'. That means it has landed," one of the hosts of the webcast said through a translator, referring to the telemetry screen. There were no scenes of cheering flight controllers or others, though, and no images or other data from the lander. "It looks like SLIM is on the surface of the Moon," one of the hosts said a few minutes later. "We are now checking the status."

One hint of a problem was displayed on that telemetry screen: the icons of SLIM on the screen, intended to show its position during its descent, showed it after landing not resting on its five shock absorbers on its side but instead on what might be considered its nose: the side of the lander opposite the main engines. It was as if a tail-dragger plane had been tipped forward so it was resting on its nose and main wheels, rather than main wheels and tail wheel. But with no updates from JAXA, it was unclear of those icons showed an accurate representation of its position or instead were a data artifact:

https://www.thespacereview.com/archive/4729b.jpg

In social media posts early Monday, the first updates provided by the mission since that press conference, JAXA said telemetry showed that the solar panels were facing west, away from the sun. "So if sunlight begins to shine on the lunar surface from the west, there is a possibility of generating power, and we are preparing for recovery," it stated.

The spacecraft stopped transmitting about two and a half hours after landing, JAXA said, to conserve its batteries, which were down to 12% at that time. The agency said it was analyzing images and data that SLIM returned during that time, and promised an update on the mission on Thursday.

IMO, the worst countries for unsuccessful probe mission status updates:

1. China (after all, the People's Liberation Army runs their space program)
2. India
3. Japan (they also suck, but not as much as the two above)

I STILL have seen no updates about the mini-rovers which are supposed to operate independently of the lander.

__________________
The other day I sat next to a woman who has a profound fear of flying. I wanted to comfort her, so I said, "Don't worry, we're not gonna' crash. Statistically, we got a better chance of being bitten by a shark." Then I showed her the scar on my elbow from a shark attack. I said, "I got this when my plane went down off of Florida." - Dennis Regan

BattleBots competitors learned early on the value of self-righting mechanisms...


Bill

__________________
It is well past time to Drill, Baby, Drill!

If your June, July, August and September was like this, you might just hate summer too...

Please unload your question before you ask it unless you have a concealed harry permit.

: countdown begin cr dup . 1- ?dup 0= until cr ." Launch!" cr ;

Give a man a rocket and he will fly for a day; teach him to build and he will spend the rest of his days sanding...

Yep, their clever last few seconds flip in orientation to horizontal to land on a slope they knew would be present due to another innovative part of their lander, the ability to land very accurately on the desired target, as explained in the video I linked above, didn't have a backup... like the ability to pulse one of the appropriate, already present thrusters to knock it into the correct orientation after landing. Someone needs to send them a copy of Murphy's Law.

__________________
The other day I sat next to a woman who has a profound fear of flying. I wanted to comfort her, so I said, "Don't worry, we're not gonna' crash. Statistically, we got a better chance of being bitten by a shark." Then I showed her the scar on my elbow from a shark attack. I said, "I got this when my plane went down off of Florida." - Dennis Regan

Other interesting details at link.

Japan?s SLIM achieved pinpoint moon landing with just one working engine
January 25, 2024

https://spacenews.com/japans-slim-a...working-engine/

Japan's SLIM lander achieved its goal of an accurate moon landing moon with only one of two main thrusters operating, JAXA stated Thursday, while a small rover returned an image of the spacecraft.

SLIM made a precise landing at 25.24889 East, 13.31549 South on the slope of Shioli crater, 55 meters from the target point, Shinichiro Sakai, SLIM team project manager at JAXA, said during a press conference early Thursday (Jan. 25), fulfilling a key mission criterion.

Sakai revealed however that one of the two main thrusters likely failed during the final landing phase. This took place from an altitude of 50 meters to touchdown, resulting in unintended lateral motion above.

"Under these circumstances, the SLIM onboard software autonomously identifies the anomaly, and while controlling the horizontal position as much as possible, SLIM continued the descent with the other engine and moved gradually towards the east."

The SLIM landing was intended to occur in two steps. First with landing thrusters down, then a smaller thruster firing to tip the spacecraft onto its side. SLIM is then cushioned by five crushable, 3D-printed aluminum lattice landing legs.

An image of SLIM taken by one of the rovers, Transformable Lunar Robot LEV-2, reveals the spacecraft to be on the lunar surface with its thruster pointing upwards. The cause of the apparent engine malfunction is being investigated.

The landing attitude meant SLIM?s solar array is facing westwards, resulting in it initially not receiving sunlight. However JAXA states there is a possibility the solar cells can generate electricity during the lunar evening as illumination improves.

"Although SLIM's activities on the Moon were originally expected to last only a few days, the necessary preparations for recovery will continue in order to acquire further technical and scientific data," a statement read.

__________________
The other day I sat next to a woman who has a profound fear of flying. I wanted to comfort her, so I said, "Don't worry, we're not gonna' crash. Statistically, we got a better chance of being bitten by a shark." Then I showed her the scar on my elbow from a shark attack. I said, "I got this when my plane went down off of Florida." - Dennis Regan