At least ispace was a softer sort of hard landing, and they will be making another attempt next year with what they learned from this one.

Even though they all happened at the same stage of of the landing process, the recent failures have all been different vehicles, so there's no data sharing of any kind on investigations to iterate changes from.

I am slightly reminded of Philae landing on comet 67P - just slightly. Which is annoying because I don't think it's reasonable, at this point, to hope for any more contact from the lander. However I am still holding out hope that we'll eventually get evidence of the lander being intact, and perhaps (as per Phil Stooke's post above) that it did manage top soft land, but something went wrong afterwards - if that proved to be the case, would this still count as a successful soft landing I wonder? Though that is kinda a semantic discussion, so maybe not appropriate here.

According to this detailed article on Spaceflight Now, the lander ran out of fuel while still at altitude, and came down hard from at least 90 meters up.

Looks like this is becoming the accepted conclusion now. The earlier report I saw about landing and taking off must be a misinterpretation.

Now... does this allow us to calculate a crash site? I haven't seen anything about that yet.

Phil

About 17 meter/sec impact velocity, discounting any residual from the descent. Ouch. Edit: The reported (tentatively) rate of drop at 90 meters was 33 km/hour, or about 9 meters a second. So we could be looking at over 26 meters a second on impact - still, well done to the team for getting to 90 meters of the lunar surface and for the hard landing (it's still a landing on the moon!) and all the data returned up to that point. Roll on mission 2!

...waiting for LROC imagery.

Yes indeed. There was an image opportunity only a few hours after landing. Presumably the image was taken, but it did not show the impact. Since we don't really know what went wrong in detail, it's not easy for those of us outside the mission to predict where the crash site should be. Did it overshoot the target? Was it off to one side? Perhaps the mission team have given the LROC people an updated target and we will get an image soon. If not a search might take a while.

Phil

Fascinating report here:

https://amsat-dl.org/en/analysis-of-hakuto-...on-2023-apr-25/


The conclusion is that the lander crashed about 99 km north of Atlas crater (depending on the angle of the final descent. This value assumes a vertical fall).

There will be a statement from ispace on 26 May.

Phil

Impact Site of the HAKUTO-R Mission 1 Lunar Lander.

http://lroc.sese.asu.edu/posts/1302

Not north of the crater as the previous analysis suggested.

Phil

With all due respect to AMSAT, I'm not seeing any error bars on their analysis, I'm not sure where they got the orbit data, I don't know what coordinate system they're using, there are some assumptions made, etc, so I wouldn't have assigned very high confidence to their result in the first place.

They do say their result assumes a vertical pitch angle and note "The landing could also have been in Atlas crater but at a pitch angle of -86.7° rather than -90° which is vertical down."

That's right. Scott Tilley also expressed reservations about the analysis:

https://twitter.com/coastal8049/status/1660127118087557126


Phil

Analysis of the failure has been released
As usual for the last few (non-China) landings, a software issue...