are you sure that the descent was unscheduled? or was it just unnannounced?

It's not in the public schedule nor in the twitter feed; of course I don't know about private schedules.

Not sure if that was posted before, but there is a very nice Space Science Review Issue about Hayabusa2 from July 2017. It wasn't free at the time I looked at it, but not no longer behind a pay wall. It's a lot of information, several very detailed papers about all the instruments and components. I especially enjoyed the papers about the impactor opration and the deployable camera.

Must read!

https://link.springer.com/journal/11214/208/1/page/1

Edit: hmm, following the link I posted and not the the google link that brought me there, it seems the issue is still behind the paywall. :-( The google link somewhat brought me behind the wall and I can access all the papers. Which is this one: https://link.springer.com/article/10.1007/s11214-017-0338-8 and then click on the issue link to go back to the overview.

New mission now confirmed by twitter , but telemetries are still not regular:
https://twitter.com/haya2_jaxa/status/1056838918694297602

"Tomorrow" in Japan already started at 15:00 UTC.

Last recorded altitude was 11332m, descending at 4 cm/s at 07:14 UTC Earth time (but uploaded to web at 17:30); 12 hours elapsed, which should mean 1728m lower, hence lower than 10000m. Target is 5000m.
Unfortunately my telemetry logger was not working for several hours due to a bug.

This version of my chart is still in beta but already quite usable: you can't yet select the data period, but you can change vertical scale and reference dates (telemetries use three dates: onboard, received and uploaded (to web) ).

https://programmi.000webhostapp.com/hayabus...dates-5000.html

https://twitter.com/haya2e_jaxa/status/1057065930927140864
HAYABUSA2@JAXA‏ @haya2e_jaxa
[BOX-C] Touchdown rehearsal, TD1-R3, is just over but we are beginning BOX-C operations. The spacecraft will perform low altitude observations at ~5km from today (October 30). After this, we plan to further lower the altitude for images near the touchdown candidate site, L08.
9:25 - 2018年10月30日

http://www.hayabusa2.jaxa.jp/topics/20181030_TD1R3_CAMH/

Image taken with a small monitor camera (cam-h) in touchdown 1 rehearsal 3 (TD1-R3). The photograph was taken from the altitude of about 21m, which began to rise on October 25, 2018 (JST) every second.
The rising speed is about 52cm/s. (Image credit: JAXA)

Jaw-dropping! Thanks for finding this, brightening up my morning Yoichi!
According to the English twitter, another target marker was dropped off and tracked autonomously.

press release in english
http://www.hayabusa2.jaxa.jp/en/topics/20181030e_TD1R3_CAMH/

Another map update to include dropping the second target marker.

Any corrections or additions including feature names are very welcome.

Phil

During past hours Hayabusa silently performed a low altitude mission, going down to 2300 m; now it's rising since 15 hours and it has reached 7400m altitude, and it's still rising at 20 cm/s.


No info about it on twitter and official site.

These images attempt showing the paths followed by H2 during TD1-R1A (right long blue path, ONC-W camera) and TD1-R3 (left short blue path, horn camera).
They are the result of the 3d reconstruction of landing site using 3DF Zephyr free, which also shows (but unfortunately does not export) calculated position of cameras.


This is the 3d reconstruction of the landing site:
https://sketchfab.com/models/95adee20ea9145...1064df8418b99c7

I don't get why they decided to land so close to a house-tall boulder.

Although not very scientific because I don't have all the needed tools and skills to perform a precise job, this model is interesting because it gives a sense of scale of the landing site:
https://sketchfab.com/models/f66ecf2b03b545...969b4d5aa81d99c

Mistery revealed (about low altitude mission of previous days): they were looking for the target maker, which is confirmed to be visible from 2.4 km away:
https://twitter.com/haya2_jaxa/status/1058612614924652544