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Posted by: Phil Stooke Mar 22 2022, 09:35 PM

SLIM is a small Japanese lunar lander planned to launch this year.

Here:

https://sorabatake.jp/25799/

is an article about it, with some images, describing two small landers which will deploy from it and operate on the surface.

In Japanese. Open in something which will offer a translation if required.

Phil

Posted by: Ron Hobbs Aug 7 2023, 07:04 PM

The launch of SLIM is now planned for August 25 Pacific Time. I saw today at NSSDC that the landing site is now near Shioli Crater.

"The landed weight will be about 210 kg, landing objective is to be within 100 meters of the target point, the ejecta blanket of Shioli crater (crater centered at approximately 13.322 S, 25.232 E)."

https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=SLIM

Go SLIM!

Posted by: Phil Stooke Aug 7 2023, 09:22 PM

Two published suggestions for the landing site.

sources:

Kushiki, K., Sakai, S., Sawai, S. et al., 2017. System design of the small lunar lander SLIM. Presented at the 17th Space Science Symposium, January 2017. Presentation P-073.

Sakai, S., 2019. To the target location on the moon. Introduction of the small lunar lander “SLIM” project. JAXA/ISAS.

Phil

Posted by: Quetzalcoatl Aug 25 2023, 08:53 PM

Delayed launch, which was scheduled today, for the "Spectroscopy and X-ray Imaging Satellite (XRISM)" and the "Small Lunar Lander Demonstration Vehicle (SLIM)" by H-IIA Launcher No. 47.


The reason for this deferral is not specified.


For the next attempt, and possibly others, the launch time will be set the day before... (Reminder: Launch window from August 27, 2023 to September 15, 2023

Posted by: Phil Stooke Aug 25 2023, 09:12 PM

I heard the reason was bad weather.

Phil

Posted by: Quetzalcoatl Aug 28 2023, 09:32 AM

Launch again postponed, wind speed too high.

Posted by: Quetzalcoatl Sep 1 2023, 06:43 AM

Bonjour,

We’re still a little foggy

https://www.mhi.com/news/230901.html

Posted by: Quetzalcoatl Sep 4 2023, 02:00 PM

SLIM must make the trip duo with XRISM

https://www.esa.int/Science_Exploration/Space_Science/Next_major_X-ray_mission_set_to_launch

Let us hope that the weather will be favourable this time.

At three days the forecasts are very reliable. We are hopeful.

Posted by: Explorer1 Sep 7 2023, 12:44 AM

Successful launch and separation!

Posted by: Phil Stooke Sep 7 2023, 06:18 AM

Now we will see if a Japanese name is given to the lander in place of its English language acronym. The Japanese custom has been to give a name after launch.

Phil

Posted by: Thorsten Denk Sep 7 2023, 07:38 AM

Is there any public timeline?
LOI? Landing?
I understand that it will be in the first months of 2024.
Thorsten

Posted by: Quetzalcoatl Sep 14 2023, 11:14 AM

Bonjour,

I don’t know the answers to these questions, but I confirm the moon landing should be done in early 2024. In the meantime, here are some short news from the probe :

https://global.jaxa.jp/press/2023/09/20230914-1_e.html

Posted by: Phil Stooke Sep 14 2023, 10:19 PM

We could narrow the landing to certain ranges of dates by looking at the date of sunrise at the landing site. SLIM uses image matching to track its location, so it needs to land in daylight and probably at least 2 days after sunrise to avoid the more extensive shadows.

Sunrise dates are 16 January and 15 February. Landings around 19 January or 18 February would seem likely.

Phil

Postscript on 5 October: 19 January is the intended date.

Posted by: Phil Stooke Oct 5 2023, 11:45 PM

https://twitter.com/SLIM_JAXA/status/1709943311770018108

Image of the Moon taken just before the flyby.

The translated text says the view is not possible from Earth, which is correct, but many media reports misinterpret that to mean the image shows the far side of the Moon. That's not true.

Phil

Posted by: Thorsten Denk Oct 8 2023, 02:11 PM

In fact, the part of the Moon's far side that would be visible in the picture is on the right in the dark lunar night.
So only the near side can be seen, albeit from an unusual perspective.

Center (cut in half): Mare Tranquilitatis
Above: Mare Serenitatis
Top left: Mare Imbrium

Thorsten

Posted by: Thorsten Denk Dec 6 2023, 02:50 PM

SLIM has a landing date and time!
https://global.jaxa.jp/press/2023/12/20231205-1_e.html

This is Friday Jan 19 at 15:20 UTC
(if I calculated correctly ).

Thorsten

Posted by: antipode Dec 26 2023, 04:49 AM

SLIM is in lunar orbit!

https://global.jaxa.jp/press/2023/12/20231225-1_e.html

P

Posted by: Phil Stooke Dec 26 2023, 07:10 PM

This is a mosaic of the frames from the little video clip taken around the time of orbit insertion, showing Plato, Mare Frigoris and Anaxagoras. They are from a navigation camera so not very detailed.

Phil

Posted by: Phil Stooke Jan 5 2024, 08:06 PM

https://twitter.com/SLIM_JAXA/status/1743212937714729320

SLIM has tested its multispectral camera by taking images from orbit. I don't have a location for the images yet.

Phil

Posted by: Phil Stooke Jan 9 2024, 03:33 AM

OK, now I do. Near the south pole.

Phil

Posted by: Phil Stooke Jan 12 2024, 07:17 PM

https://twitter.com/SpcPlcyOnline/status/1745862074922672342

SLIM landing date and time from Marcia Smith. If it lands successfully the Peregrine 1 impact will occur during SLIM surface operations.

Phil

Posted by: Phil Stooke Jan 15 2024, 08:00 PM

SLIM dropped its apolune to enter a c. 600 km circular orbit on the 14th. Here is a mosaic of images from the navigation camera made at the time.

It's just on the far side with Compton near the top centre and Schwarzschild the largest crater in the lower part of the mosaic.

Phil

Posted by: Phil Stooke Jan 15 2024, 08:32 PM

Putting it in context.

Phil

Posted by: Hungry4info Jan 19 2024, 02:27 PM

Just under an hour from landing.
English live coverage.
https://www.youtube.com/watch?v=nvXLt3ET9mE

Posted by: nprev Jan 19 2024, 02:54 PM

Live blog updates in English https://www.nytimes.com/live/2024/01/12/science/japan-moon-landing-slim. Landing expected at 1020 EST/1520 GMT.

Posted by: Hungry4info Jan 19 2024, 03:01 PM

De-orbit burn has started.

Posted by: nprev Jan 19 2024, 03:22 PM

Looks like it landed per telemetry, awaiting confirmation.

Posted by: kenny Jan 19 2024, 03:27 PM

IT seems to be landed and transmitting. IMU data on the screen is changing...

Posted by: Hungry4info Jan 19 2024, 03:28 PM

It's definitely alive on the Moon. Lots of "We are checking the status, please wait."
In the mean time the battery indicator suggests the battery is draining -- shouldn't it be charging if it landed in a correct orientation?

Posted by: nprev Jan 19 2024, 03:32 PM

Live coverage ended, awaiting press conference. Yeah, I dunno...didn't get a happy feeling.

Posted by: JTN Jan 19 2024, 03:37 PM

The (telemetry-driven?) sprite on the webcast seemed to flip over on landing, and there were noticeable deviations on the ωX/Y/Z °/s dials. Hope that's not real...

Posted by: kenny Jan 19 2024, 03:38 PM

Press conference coming up "shortly" here, says the commentator...

https://www.youtube.com/watch?v=2-yBlZplnKQ

Posted by: nprev Jan 19 2024, 03:50 PM

Audio-only on the JAXA feed right now in Japanese...essentially, they're 'still checking'.

Posted by: marsbug Jan 19 2024, 03:54 PM

As per https://eyes.nasa.gov/dsn/dsn.html</a> There is definitely a signal from the lander, which at least rules out it having smacked into the regolith at tens of meters a second.

Posted by: JTN Jan 19 2024, 04:04 PM

https://wandering.shop/@skrishna/111783448807596673 claims it was supposed to tip over.

Posted by: Hungry4info Jan 19 2024, 04:08 PM

We're also getting telemetry from one of the rovers.
https://twitter.com/amsatdl/status/1748374331715981601

The IMU data suggests it's in the incorrect post-tip-over orientation, with the engines pointing up. Not sure how reliable that is though.

Posted by: marsbug Jan 19 2024, 04:18 PM

While it looks like things have not gone flawlessly, JAXA has an at-least-partly-functional vehicle on the Lunar surface. So I think it's time to say 'well done JAXA and the SLIM team'. At lot of smart and determined folks have tried this and ended up as a crater to be imaged by LRO.

Posted by: Explorer1 Jan 19 2024, 04:29 PM

If the rovers were deployed before touchdown, as per the plan, they could still accomplish their mission (since they can communicate directly with Earth)? Images would be very enlightening.

Posted by: Hungry4info Jan 19 2024, 04:38 PM

Andrew Jones reports radio detection of... something

https://twitter.com/coastal8049/status/1748383389517004815

This feels like a Hayabusa-esque "Trying to fix an emergency in real time with scant data" situation. Fun!

Posted by: Explorer1 Jan 19 2024, 04:49 PM

They still had plenty of spare fuel at the time of touchdown. If it's on the wrong side, it may be possible to right it?

Posted by: Thorsten Denk Jan 19 2024, 04:54 PM

Maybe they are still able to correct the wrong attitude with the RCS thrusters?
That would be really daring...

Thorsten

Posted by: Hungry4info Jan 19 2024, 04:54 PM

That may have been what the change in Doppler behaviour of the SLIM signal suggests occurred.
Scott Tilley now reports:

No idea what this means, or even if it's bad news.

Press conference has started!
Edit: Nope! It was just an update to tell us that they'll start at 2:10 local (13 minutes from now).

Posted by: kenny Jan 19 2024, 05:02 PM

News conference will start, and press release on JAXA web site, at 10mins past the current hour. ie. 02.10am in Japan Standard Time.

Posted by: nprev Jan 19 2024, 05:07 PM

News conference at 1210 EST/1710 GMT!

Posted by: JTN Jan 19 2024, 05:18 PM

"it seems that solar cell is not generating electricity"

Posted by: nprev Jan 19 2024, 05:19 PM

Conference underway. Thus far:

1. Landed successfully.

2. Power-negative; battery not charging (as Hungry noticed.)

3. At least one of the little rovers landed successfully as well.

Posted by: JTN Jan 19 2024, 05:29 PM

https://www.jaxa.jp/press/2024/01/20240120-1_j.html. Machine translation:

Posted by: Explorer1 Jan 19 2024, 05:32 PM

Looks like the LEV 1 and LEV 2 are both working, they are getting images back now.....

Posted by: JTN Jan 19 2024, 05:41 PM

From press conference, there is hope that even once the battery is depleted (in several hours), as the sun angle changes, the solar panels may start producing power and revive the lander. In the meantime they're prioritising getting data back over recovery operations.

(However, a couple of posts (https://spacey.space/@kenthebin/111783800651179608, https://social.brucknerite.net/@brucknerite/111783805164075315) claim a heater has been turned off to conserve battery power -- I didn't catch this myself -- dunno what this means for the longevity of the lander.)

Posted by: Hungry4info Jan 19 2024, 05:46 PM

I heard the comment about the battery as well. They seemed to imply that its what would allow the battery to last for "several hours."

Someone finally asked a decent question. Is there no power being generated by the solar panels? Or just an inadequate amount to keep up with the battery discharge? Answer was that they don't yet know, pending data.

Posted by: Thorsten Denk Jan 19 2024, 05:55 PM

If I combine this picture of the landing site (downslope towards WNW)
http://www.unmannedspaceflight.com/index.php?act=attach&type=post&id=53653
with the PV cells orientation from the loanding telemetry (towards +X; +Y is downslope),
then the PV cells should be facing north / slightly to the east (NNE).

This would mean (at 13°S) that in fact the ilumination could improve a little bit in the coming days.

(Just a very quick over-the-thumb analysis from my side, might be wrong)

Thorsten

Posted by: akuo Jan 19 2024, 05:56 PM

Congratulations for a soft landing on the Moon.

Is restarting of the engines possible for SLIM? For an attempted hop or attitude change.

Posted by: nprev Jan 19 2024, 05:56 PM

One thing I noticed and don't understand is that the IMU (lower left corner) was showing normal lunar surface gravitational acceleration at landing but the bar changed color from green to yellow. Don't know what the color coding indicates, but given the attitude graphic does this imply that the lander is indeed upside down?

That would explain the array not charging, but if so why are they getting telemetry unless it has a very robust omni antenna? Or maybe there's one on the ventral surface for use during cruise.

Posted by: Hungry4info Jan 19 2024, 06:04 PM

From https://forum.nasaspaceflight.com/index.php?topic=37353.msg2560109#msg2560109, it seems there's several antennas all around the spacecraft.

Posted by: Hungry4info Jan 19 2024, 06:14 PM

Loss of Signal.
- from https://twitter.com/coastal8049/status/1748405279966773326,
- from https://twitter.com/amsatdl/status/1748406388181676391.
Not sure if this genuinely means mission LOS or if it just finished transmitting something.

Posted by: mcaplinger Jan 19 2024, 06:22 PM

Presumably the lower left is the vector sum of the three accel axes and doesn't say anything about orientation, and they only display the angular rates, not the absolute angles. But one imagines they wouldn't draw it upside down if it weren't in fact oriented that way.

Posted by: kenny Jan 19 2024, 08:24 PM

NASA's Deep Space Network is currently showing no radio traffic with SLIM. There was steady download during the first few hours after the landing.

Live feed from DSN:

https://eyes.nasa.gov/dsn/dsn.html

This is not in any way a negative indication of the state of the spacecraft - radio traffic can be expected to stop and start.

Posted by: Phil Stooke Jan 20 2024, 07:21 AM

I have added SLIM to my Moon map. It is here:

https://publish.uwo.ca/~pjstooke/moon-sites-map.jpg


Phil

Posted by: Thorsten Denk Jan 20 2024, 10:03 AM

Great map, Phil!
Is there also a version including only the landers and impactors (successful and unsuccessful), but not the upper stages and orbiters?

----

Excellent 12min Video analyzing the Slim landing from Scott Manley:
https://www.youtube.com/watch?v=muK6gFtv7_o

The solar panels might point westwards.
This means that from in a week or so they might start generating power.

Thorsten

Posted by: Phil Stooke Jan 22 2024, 07:11 AM

Thanks, Thorsten. I don't have a different version of the map.


Here's a JAXA tweet with welcome news (but no images released yet)


https://twitter.com/SLIM_JAXA/status/1749295017427108233

着陸後、電源OFFするまでの間に、着陸降下中や月面で取得した技術データや画像データの地上への送信を完了できました。現在、そのデータの詳細な解析を行っています。プロジェクトチームとしてはたくさんのデータが取得できたことを確認し、ほっとするとともにワクワクしはじめています。
#JAXA #SLIM
Translated from Japanese by
After landing, until the power was turned off, the technical data and image data acquired during the landing descent and on the lunar surface were successfully transmitted to the ground. We are currently conducting a detailed analysis of that data. As a project team, we are relieved and excited to see that we have been able to obtain a large amount of data.
#JAXA #SLIM
8:56 PM · Jan 21, 2024



From published views of the lander it appears that the multispectral camera is facing sideways as intended, and if they were able to operate it, or are able to when the sun reaches the array, it should provide good data.

Phil

EDIT:

https://twitter.com/SLIM_JAXA/status/1749320754628546849


We are preparing to announce the status of #SLIM and current results at the end of the week. Although the attitude after landing did not go as planned, we are glad we could achieved so much and are happy to have landed successfully. We’re also excited to analyse the data. #JAXA


Another point... The multispectral camera is not a panoramic camera, it will take images covering an area about 50 by 70 degrees across. But perhaps the navigation cameras are also able to take images on the surface so a partial panorama might emerge.

Posted by: Thorsten Denk Jan 22 2024, 08:44 AM

It appears that in fact the solar panels are facing west!
https://twitter.com/Cosmic_Penguin/status/1749312587131756589

Will there be generated solar power some time after local solar noon?

Thorsten

Posted by: mcaplinger Jan 22 2024, 05:51 PM

That's what that tweet says, yes. Presumably JAXA has good orientation data from the images they have received but not yet released.

Posted by: Thorsten Denk Jan 22 2024, 08:38 PM

This was actually intended as a rhetorical question.
We'll see what happens.

And it appears that the telemetry data of the probe's orientation in the live broadcast was indeed correct.
The solar cells there also faced west.

Thorsten

Posted by: Phil Stooke Jan 24 2024, 07:52 AM

https://twitter.com/AstroKovacs/status/1749741343553810552

Hungarian @astroKovacs has tweeted a very nice visualization of what might have made SLIM come to rest in such an apparently precarious orientation. The suggestion is that it may be touching a rock or a small crater wall rather than completely free-standing. We may know more about this on Friday.

Phil

Posted by: mcaplinger Jan 25 2024, 02:22 AM

Still nothing detected but JAXA was continuing to sweep/command as of 9 hours ago. Maybe tomorrow. https://nitter.net/coastal8049

Posted by: Hungry4info Jan 25 2024, 05:35 AM

From the JAXA Livestream update here -> https://www.youtube.com/watch?v=U61i0wN01Uk

My Japanese is non-existent but these look like surface images to me!

Posted by: Hungry4info Jan 25 2024, 05:37 AM

It seems there was some kind of engine failure during landing. If I understand this right, one of the engine nozzles seems to have followed its own independent landing trajectory.

Posted by: Hungry4info Jan 25 2024, 05:42 AM

They've confirmed that the lander is resting on the surface nose-down as expected.

Posted by: Hungry4info Jan 25 2024, 05:45 AM

Oh wow! From LEV-2. (edited - originally wrote LEV-1).

Posted by: Phil Stooke Jan 25 2024, 07:16 AM

And it looks like it has just one nozzle on top. The second nozzle broke off during the hover phase.

Phil

Posted by: Phil Stooke Jan 25 2024, 08:20 AM

https://www.isas.jaxa.jp/home/slim/SLIM/assets/img/landing/press_20240125.pdf

Slides in Japanese - get that translator software fired up!

Phil

Posted by: antipode Jan 25 2024, 08:27 AM

That's an extremely scenic bit of (Lunar) terrain!

Any ideas about why the nozzle broke off?

Didn't Akatsuki also break a nozzle (I know, different time/place)?

P

Posted by: Explorer1 Jan 25 2024, 02:00 PM

Very cool images! Hopefully it can start working again soon (and if so, could it be righted with the remaining fuel on board)?
I wonder if any sign of the nozzle breakup is visible in that detailed telemetry we had from landing.
Yes, it was Akatsuki that lost a nozzle when attempting Venus orbit insertion. Note sure if it's the same type of engine or not....

Posted by: kenny Jan 25 2024, 02:43 PM

The falling nozzle is visible in this PDF PPT; look at slide 9, Right image. The camera has snapped the detached nozzle falling away. The Left image shows the same background terrain without the nozzle. Both views were taken by the navigation camera, looking straight down.

https://www.isas.jaxa.jp/home/slim/SLIM/ass...ss_20240125.pdf

The nozzle is also visible a few slides later...

Posted by: Olympusmonsuk Jan 25 2024, 03:01 PM

This view is looking approximately SE I believe.

Posted by: kymani76 Jan 25 2024, 03:12 PM

With today's images and https://spacenews.com/japans-slim-achieved-pinpoint-moon-landing-with-just-one-working-engine/ I am finally in position to offer landing map.
Article reports 25.24889E, 13.31549S as landing site, I get 25.253834E, 13.31406S from LRO NAC image M1249381781LC.

Close up with navigational images. Grid at 10m.

Posted by: kymani76 Jan 25 2024, 03:22 PM

3D view looking SE towards Cyrillus crater edge, roughly the same direction as the one from the LEV-2 photo released today.
SLIM really landed on a pronounced slope!

I also came across a photo with few rocks labeled.

Posted by: propguy Jan 25 2024, 03:30 PM

I did some digging and it may be the same engine (or at least a 2nd/3rd generation of the Akatsuki main engine). Akatsuki did use a 500 N ceramic engine and from the SLIM press kit they mention the same attributes for their main engine. Akatsuki failed due to a stuck fuel side pressurization check valve. No way to know if this was a similar issue (but one thing I know after 37+ years of prop experience is we usually overkill issue issues that occur on previous missions, so most issues are new ones). Sadly the Akatsuki failure put big dampers on development and use of ceramic larger thrust engines and this failure may have the same effect. Lets hope in the current position that SLIM can still produce power when the arrays are illuminated and recover some of their mission.

Posted by: Phil Stooke Jan 25 2024, 08:46 PM

Trying to understand the viewing geometry in the surface images. This image shows a composite of the MBC image and the LEV-2 image to maximize viewing of the horizon (incidentally, although this LEV-2 image was relayed to Earth via the LEV-1 hopper, it seems that LEV-1 did not obtain any images). Below is an LROC view from Quickmap showing approximately the field of view of that composite. A prominent crater below the distant horizon ridge is discernable in the composite as a very bright spot on the right side of the lander (high sun LROC images show it has bright ejecta).

Also, a shadow-filled crater half visible on the left edge of the LEV-2 image is seen in Jake's map just to the east of the lsnding site.

Phil

Posted by: MichaelJWP Jan 25 2024, 11:40 PM

Not to cast doubt, but this image looks strange in that the background beyond the close up ridge looks a bit out of focus, depth of field fair enough, but the horizon ridge appears sharp, yet pixellated.
As well as that, the background looks brownish compared to the monochrome foreground.
Wondered if any pic experts couid explain? (there are a few sceptics on social media claiming it's not real)

- Michael

Posted by: nprev Jan 26 2024, 01:17 AM

Such "skeptics" are more accurately characterized as "conspiracy theorists". Per Forum rule 1.9 such nonsense is not a permissable area of discussion.

Posted by: Phil Stooke Jan 26 2024, 07:36 AM

I have learned a few things about the multispectral camera image. What we have seen so far is a low resolution monochrome survey of the field of view available to the instrument. It consists of 257 individual small frames. A total of 333 were supposed to be taken but the sequence was cut short to be sure it could all be transmitted. If SLIM is revived as the sun reaches its solar panel, a set of 10-band multispectral images will be taken of specific targets identified in the existing image. Those targets are presumably the six rocks identified by names (breeds of dog) in one image.

Phil

(EDIT: I corrected the numbers of frames)

Posted by: marsbug Jan 26 2024, 11:13 AM

Having read the above reminder of rule 1.9 I should probably be clear that I am asking because I'm interested in the technology of the LEV-2 mini rover and where it might go from here: My own searching has thrown up precious little on the specifics of the LEV-2 cameras, and how they are oriented and operate - except that control board for them was designed with maximum energy efficiency in mind, by Sony. Does anyone have any directions or links to a more detailed break-down of them? EDIT: I'm aware that the rover was made by TOMY, a toy manufacturer, but I've not found anything in the way of technical material on their website.

Posted by: MichaelJWP Jan 26 2024, 11:16 AM

Quite rightly so, but I was more interested in technical reasons (such as compression artifacts etc.) informing why the photo might look like that, not to discuss conspiracy nonsense.

Posted by: climber Jan 26 2024, 03:54 PM

LRO found SLIM : https://x.com/nasascienceaa/status/1750896380627808682?s=46&t=1zUy6syfWw235ADkQ7vfxA

Posted by: Explorer1 Jan 26 2024, 04:01 PM

Wrong link? It's discussing the retroreflector from the Vikram lander.

Posted by: climber Jan 26 2024, 06:29 PM

Still working alright for me, don’t know what to do about it, sorry…

Posted by: tolis Jan 26 2024, 07:36 PM

A http://lroc.sese.asu.edu/posts/1358 has just appeared at the LROC website.

Posted by: Explorer1 Jan 26 2024, 07:45 PM

https://science.nasa.gov/missions/lro/laser-instrument-on-nasas-lro-successfully-pings-indian-moon-lander/?utm_source=TWITTER&utm_medium=NASAScienceAA&utm_campaign=NASASocial

I found it on the LROC website: https://www.lroc.asu.edu/posts/1358
Looks like some exhaust kicked up, but still hard to resolve anything.

Posted by: kymani76 Jan 27 2024, 12:55 AM

SLIM being imaged by LRO allows me to make a minor correction, it turns out the lander is about 10m to the south of the previous estimate.
In rounded numbers I get 25.254, -13.315 for long/lat of the landing coordinates, a slight difference from the estimate of 25.251, -13.316 reported in LRO release.
SLIM is visible, but is just a few pixels across in size.

Posted by: Thorsten Denk Jan 28 2024, 09:08 PM

It seems that SLIM is emitting radio again...
https://twitter.com/amsatdl/status/1751701647640732152

Thorsten

Posted by: Phil Stooke Jan 28 2024, 09:56 PM

https://twitter.com/coastal8049/status/1751723650372538717

Scott Tilley agrees with this. I really hope the MBC can be operated in the c. 3 days we have left before sunset.

Phil

Posted by: HSchirmer Jan 28 2024, 10:51 PM

I've seen some speculation that the press release's mention of a pressure-fed-blow-down 2 engine system could be important. As the fuel / oxidizer tanks drain low, if one engine started to run fuel rich and the other runs oxygen-rich, the hotter oxygen rich side might have burned through / thermal shocked the ceramic nozzle.

Posted by: Hungry4info Jan 28 2024, 11:42 PM

JAXA confirms resumption of the mission and science activities.
https://twitter.com/SLIM_JAXA/status/1751742976253190226

Google Translate:

(toy poodle? either a translation error or I don't know what a toy poodle looks like, which is quite possible)

Edit: Oooh!

Posted by: tolis Jan 28 2024, 11:50 PM

I think "Toy Poodle" refers to one of the rocks in the immediate vicinity of SLIM.

Posted by: Phil Stooke Jan 29 2024, 12:33 AM

Yes, it does - look at post 77 in this thread.

Phil

Posted by: Phil Stooke Jan 29 2024, 07:37 AM

Now. a report of a possible detection of Lev-1 transmission.

https://twitter.com/PI9CAM/status/1751657240728117705

Phil

Posted by: Phil Stooke Jan 30 2024, 04:15 AM

updates copied from @SLIM_JAXA tweets in the last few minutes:

------------------------
Small lunar landing demonstration vehicle SLIM
@SLIM_JAXA
·
17m
From 9:00 pm last night to 9:00 am today, we operated SLIM using deep space antennas at 34 m at Uchinoura and 64 m at Usuda. So far, the power generation from the solar cells is normal, and the SLIM is operating without any problems with the power from the solar cells.
Small lunar landing demonstration vehicle SLIM
@SLIM_JAXA
·
17m
In this operation, we were able to perform multi-band observations of Akita Inu, Kai Inu, Saint Bernard, Shiba Inu, Beagle, and Tosa Inu using the spectroscopic camera! Beagle and Tosa Inu are new observation subjects that have been added to the observation list after restoration.
Small lunar landing demonstration vehicle SLIM
@SLIM_JAXA
·
17m
The next observation will be from 22:00 today (1/30) to 9:00 tomorrow (1/31). Please note that SLIM will be dormant for a while after February 1st.
-----------------------------


I assume the 'dormant' comment refers to the lo---ooooo---ooong lunar night.

Phil

Posted by: Phil Stooke Jan 31 2024, 02:44 AM

https://twitter.com/SLIM_JAXA/status/1752520549962822122

This tweet translates via Google as:

From 10pm last night (1/30) to 9am today (1/31), we conducted multiband observations using a spectroscopic camera. Last night, new Labradors, Dalmatians, Papillons, and more were added to the group as a result of detailed analysis of the images and additional imaging results, and we are also conducting second observations of some of the objects.

More dogs! I hope they stay in the off-leash park. I was working on an illustration but may need to rethink it if it gets too crowded for the scale I was using.

Phil

Posted by: Hungry4info Jan 31 2024, 06:28 PM

Before/after our battery-imposed "nap" showing the lunar landscape just after landing versus after regaining contact.
Edit: No the daylight image is edited a bit. See below.
https://www.isas.jaxa.jp/home/slim/SLIM/operation_status/index.html

Posted by: Phil Stooke Jan 31 2024, 10:50 PM

Beautiful! These seem to be uncompressed Navigation Camera images.

Phil

Posted by: fredk Jan 31 2024, 11:37 PM

When you extract the two frames from the gif on the page Hungry linked to, the morning (?), better-lit frame shows clear 8x8 compression blocks - maybe DCT blocks? But the later frame (dark foreground) shows no sign of compression.

(Hungry seems to have partially merged the frames while extracting?)

Posted by: Phil Stooke Jan 31 2024, 11:45 PM

The GIF does use a compressed version of the morning frame, but the single image does not appear compressed.

Phil

Posted by: Hungry4info Feb 1 2024, 06:44 AM

Forgive me I just grabbed the images from Seger Yu https://twitter.com/SegerYu/status/1752691007836274772 (where I learned of the JAXA gif release). I see now the "daylight" image I posted was a modified image. Apologies about that.

Posted by: Hungry4info Feb 1 2024, 05:25 PM

Another update from JAXA, with some images we haven't seen.
https://www.isas.jaxa.jp/topics/003674.html

Posted by: Phil Stooke Feb 14 2024, 05:51 PM

I put together a rock map for SLIM. It's only approximate but I think one or two of the largest rocks are just visible in the LRO images. If we get an OHRC image of this location, several of the rocks should be very clearly identifiable.

Phil

EDIT: I noticed that I had to rotate the lander 180 degrees on the map - I have replaced the map, so if you downloaded the old one, this is the one you really need.

Posted by: nogal Feb 16 2024, 01:01 AM

A February 14 article in APNews, covering the analysis of rocks by SLIM and their implications for the Moon's origin theory, hints at the possibility of a reawakening in late February:

Link: https://apnews.com/article/japan-jaxa-moon-origin-landing-slim-5cedd3d0e0caf844c480f8b6b9d5cd93

Fernando

Posted by: Cosmic Penguin Feb 26 2024, 05:15 AM

JAXA has announced they have managed to re-contact SLIM briefly yesterday, although only a brief contact was done due to high temperatures within the lander. They will continue contact in the coming days.
https://twitter.com/SLIM_JAXA/status/1761981979237732355

Posted by: Phil Stooke Feb 28 2024, 07:25 AM

The navigation camera image from the brief contact with SLIM:

https://twitter.com/SLIM_JAXA/status/1762671786775490715

and the plan for the Multi-Band Camera in the next day or two:

https://twitter.com/SLIM_JAXA/status/1762095220743930163


Phil

Posted by: Phil Stooke Mar 1 2024, 08:05 PM

The second lunar day is now over. MBC did not operate so no new data were obtained from it in day 2. The navigation camera took the image linked in the last post and another just before sunset.

Phil

https://twitter.com/SLIM_JAXA/status/1763516934333849705

Posted by: Hungry4info Mar 28 2024, 03:49 AM

SLIM woke up for a third lunar day. As before, it's rather warm so they aren't doing much. But they did get another camera shot of the same view we're all used to.
https://twitter.com/SLIM_JAXA/status/1773190431758508138

Posted by: Phil Stooke Apr 1 2024, 03:05 AM

Here is a very nice new image from SLIM on its last day of operation during lunar day 3, with less shadow than seen during the previous late afternoon images.

https://twitter.com/SLIM_JAXA/status/1774608981098729732

Phil

Posted by: Phil Stooke Apr 8 2024, 05:20 AM

https://twitter.com/SLIM_JAXA/status/1777186920650649997

Two very nice GIF representations of SLIM's NavCam images: chronological and by local time.

Phil

Posted by: Phil Stooke Apr 11 2024, 07:03 AM

Here is an excellent representation of the SLIM landing site with at one point an estimate of Sora-Q's location.

https://www.isas.jaxa.jp/home/slim/SLIM/assets/img/landing/LandingSite.mp4

Phil

Posted by: Hungry4info Apr 24 2024, 02:34 AM

A fourth lunar Day and an image taken earlier in the day than before.
https://twitter.com/SLIM_JAXA/status/1782956426752848056

Posted by: Phil Stooke Apr 26 2024, 08:12 PM

Here is a tweet from Chandra ( @this_is_tckb ) about finding SLIM in a new OHRC image (16 March 2024).


https://twitter.com/this_is_tckb/status/1783084056734789992


The image is very interesting. Its resolution is good enough to identify some of the rocks south of the SLIM lander. But there's a puzzle too. Immediately southwest of the lander is a bright spot which looks to be about 70 cm across and not very high (it casts a short shadow in this very early morning image). The LEV-2 image of the lander on the surface doesn't show anything on the ground there, though I think it should be visible. It is far too close to the lander to be the broken rocket nozzle. It could be a mostly buried rock or some object - maybe a bit of a solar panel or thermal blanket - which fell off the lander during its eventful landing. Could it be LEV-1? I don't think so but it might be possible.

Phil

Posted by: Hungry4info Apr 26 2024, 08:34 PM

Could it be a reflection of sunlight off the lander onto the ground? How real is that shadow? We didn't see it in the LRO image.

Posted by: Phil Stooke Apr 26 2024, 09:25 PM

The only post-landing LRO image I have seen is taken with very high sun. There are several long shadows from rocks in the image. I don't see why it would not be real.

A light reflection... that's a good suggestion. We've seen that with (e.g) Yutu and Yutu 2. I'm not sure the geometry is right but I will think about it.

Phil

Posted by: Hungry4info Apr 27 2024, 04:38 AM

My point about the LRO image is exactly that it had a difference in the solar illumination angle, which might affect the visibility/location/existence of reflections. I definitely agree though that it's not clear the geometry for a reflection makes a lot of sense.

Posted by: Hungry4info Apr 30 2024, 01:29 AM

SLIM took a photo looking north from one of it's star trackers.
https://twitter.com/SLIM_JAXA/status/1784896327270232091

Posted by: Phil Stooke May 3 2024, 05:04 AM

A bit more on that curious little bright spot adjacent to the SLIM lander:

https://twitter.com/this_is_tckb/status/1785878807557099996

This link goes to a tweet from the same person who posted the SLIM image, but it refers to an OHRC image of Chandrayaan 3. It also shows a small bright spot right next to the Vikram lander. The poster, Chandra, suggests it is Pragyan but it is in the wrong place. ISRO's map and a second map show Pragyan about 33 m northwest of the lander, and I have shown that it is visible at that location casting a shadow in an LRO image. And that same object is casting a long shadow in this new image too so the bright spot certainly is not Pragyan.

So, two OHRC images both showing a very bright lander at low sun and a small bright spot right next to it. I think it is an artifact, perhaps caused by an internal reflection in the camera and showing up because the real image of the lander is so bright.

Phil

Posted by: fredk May 4 2024, 03:09 PM

An internal reflection should tend to appear along a radial line passing through the bright source and the optical axis (centre of frame). Considering the full frame, is that the case here?

Posted by: Phil Stooke May 6 2024, 06:04 AM

I don't know where this is in the full frame.

On the SLIM website:

https://www.isas.jaxa.jp/home/slim/SLIM/gallery/index.html

a caption to this OHRC image notes: "It is unclear what the light spot in the immediate vicinity of SLIM is, but it appears to be about LEV-1 in size."

I had considered that, but I was puzzled by the appearance of a small bright spot adjacent to two different landers in images taken by the same camera. I looked for a common cause but I was probably wrong to do so. The LEV-2 image of the lander doesn't show anything at that location but the position of LEV-2 is not known yet, so LEV-1 might be hiding behind the lander.

Phil

Posted by: Hungry4info May 30 2024, 02:26 AM

SLIM did not survive the last lunar night. The mission is over.
https://x.com/SLIM_JAXA/status/1795310224548798726

Posted by: Phil Stooke May 30 2024, 10:39 PM

Probably the end but not necessarily:


https://x.com/SLIM_JAXA/status/1795310331209904222

"Small lunar landing demonstrator SLIM
@SLIM_JAXA
We plan to try operating it again next month when it is expected that there will be sufficient solar power generation. The power was turned off overnight, so we hope that the whole system will be reset and restarted. #SLIM #JAXA
9:25 PM · May 27, 2024"


Phil

Posted by: Phil Stooke Jun 23 2024, 07:41 PM

If that slight chance for SLIM to wake up again is still thought possible, right about now is when it should happen. I expect JAXA will be trying, but no word yet.

Phil

Posted by: Phil Stooke Jul 22 2024, 04:39 AM

Well, it didn't wake up. But here is a new view of SLIM from LRO on 14 April 2024, at dawn, casting a long shadow. The image number is in the filename if you save it.

Phil

Posted by: Phil Stooke Jul 30 2024, 12:10 AM

SLIM news:

https://x.com/SLIM_JAXA/status/1817867601244221572

https://x.com/SLIM_JAXA/status/1818074276760797255


These two tweets reveal that JAXA tried again on 24 and 25 July to contact SLIM, without success. But they are still trying!

... and that LRO has successfully received laser reflections from SLIM's laser reflector, despite it being in a very tricky orientation.

Phil