Mission: Hayabusa 2 Options

[pandaneko]

Radio silence, well, almost...

Due here, I think, is a little poem in traditional Japanese Haiku way.

Hayabusa 2

Doubling Ryugu to

Christmas

P

[pandaneko]

1 June ( 36km/h): 16/11/18/10/15/13/19/8/9/9/7/8
2 June ( 36km/h): 16/11/18/10/15/13/19/8/9/9/7/8
3 June ( 36km/h): 16/11/18/10/15/13/19/8/9/9/7/8
4 June ( ?km/h): 16/11/18/10/15/13/19/8/9/9/7/8
5 June ( 9.2km/h): 16/11/18/10/15/13/19/8/9/9/ 8 /8

As we can see thruster 11 was used for one second. I will stop carrying this matrix here now
as we know that we are really into the final stage.

P

[Guest_mcmcmc_*]

Questions?
http://planetary.jp/hayabusa2/FAQ/index.html


Upcoming press conference:

The asteroid explorer "Hayabusa 2" is now sailing smoothly towards the asteroid Ryugu (Ryugu). "Hayabusa 2" came to a stage where the continuous operation of the ion engine ended on June 3 and approached the rugou with optical navigation.
At this briefing session, we will explain the current situation of "Hayabusa 2", the ion engine that finished the last continuous operation on the outbound route.


Date and time 11: 00-12: 00 (Thursday) June 7 th, Heisei 30 th (02:00 GMT, 07/JUN/2018)


Speaker (planned):
JAXA Institute for Space and Astronautical Science "Hayabusa 2" Project Team Mission Manager: Makoto Yoshikawa (Associate Professor, JAXA Institute of Space and Astronautical Science and Engineering)
Kazutaka Nishiyama 　(JAXA Institute of Space and Astronautical Science Associate Professor of Engineering Research)

http://fanfun.jaxa.jp/jaxatv/detail/12042.html

[pandaneko]

Thank you, mcmcmc

The deadline for questions was 1 June, but I looked into Qs&As and found some are interesting. Some are more technical than you may
think, coming from amateurs. I will translate some over the next 10 days or so. After all, there is not much else I can usefully do.

In the meantime I now know from my log that 6 of the 12 chemical thrusters have been fired over the last 36 hours.

I will also translate the contents of tomorrow's press conference, if there is something interesting or new to us.

P

[Guest_mcmcmc_*]

Thank you, mcmcmc

The deadline for questions was 1 June,

I didn't read anything about end date, so I tried compiling the form and it was accepted, so let's see.
Anyway there are several questions dated after 1 june.

I will also translate the contents of tomorrow's press conference, if there is something interesting or new to us.

That would be great, thanks.

[pandaneko]

What follows is an extrat from JAXA Q&A collection. More will follow during the next few days.

Q. When will we be able to see the shape of Ryugu?
June 03, 2018 - : 64 year old

A. We will be abe to see the rough shape in mid June. We can find its precise shape when
Hayabusa 2 arrives at the asteroid and get data. If the axis of rotation is not perpendicular to
the plane of the ecliptic it will take longer to get the whole view of Ryugu, meaning that it may
be up to a few months before we know its precise shape.

Q. What is the prediction by the project team about Ryugu's water?
June 02, 2018 - : 14 year old

A. Water will not exist in the form of liquid or solid water. Water molecules will be contained in the
minerals of Ryugu. So, we will not be finding Ryugu to be wet or affected by moisture in any way.

Q. When can we see clear pictures of Ryugu?
June 02, 2018 - : 47 year old

A. It will be when we get to Ryugu. Rough shape, we will be seeng in mid June.

P

PS. I realise that questions were perhaps accepted even after the deadline of 1 June,
by the look of the dates here.

[Guest_mcmcmc_*]

Press conference outcome (in japanese):
http://fanfun.jaxa.jp/jaxatv/files/20180607_hayabusa2.pdf

[pandaneko]

Following URL has shapes and appearances of Ryugu as imagined by those people in the project
team.

http://www.hayabusa2.jaxa.jp/topics/20180605/

Each picture is numbered, and 4 to 10 (this 10th fellow is the person who does the twittering),
12 to 37 are all those people in the team.

Since the volume of the press conference itself is rather a lot I will translate only some of them.

P

[pandaneko]

On page 13 of the press conference report there is a picture of Ryugu as seen at 04:15 JST on
6 June by the telephoto camera, ONC-T.

Shape is unknown, exposure time of 0.09 second, one pixel is
equivalent to 22 arc second, 0.3 km at 2600km distance.

There are interesting remarks in this press report, most of it is already known to us, but there
are new inputs. I will translate them very soon.

P

[pandaneko]

According to the same JAXA press report of today there will be another press conference on
14 June with more detailed information. The arrival time is thought to be 27 June, but it may
be a few days earlier or few days later than 27th, according to this report.

P

[pandaneko]

P6
Current status:
　－2100km as of today, 7 June
　－Ion eigines stopped on 3 June for onward journey
　－Arrival expected to be 27th June +/- few days
　－Optical navigation is underway
P7
・Delta V since 10 January is 393m/s
・Outward operation of the ion engines is now over
・24 kg of zenon consumed, 42kg still remains, total delta V is 1015m/s
P10
・Optical navigation means approaching with camera views
・Reason for above: cordinate uncertainty of about 220km

These are the new (at least to me) inputs in the press conference report about current status
of Hayabusa 2.

P

[Guest_mcmcmc_*]

[pandaneko]

Ryugu is not symmetrical, is it? Top one third looks darker.

P

[Guest_mcmcmc_*]

Future repositories for images?
http://www.darts.isas.jaxa.jp/pub/hayabusa2/onc_bundle/l2a/
http://www.darts.isas.jaxa.jp/pub/hayabusa...dle/browse/l2a/

Source:
http://www.darts.isas.jaxa.jp/pub/hayabusa..._bundle/browse/

[fredk]

Ryugu is not symmetrical, is it? Top one third looks darker.

Almost impossible to say yet. If Ryugu's centre is a bit below the centre pixel you'd expect the upper pixels to be darker than the bottom ones.