Mission: Hayabusa 2 Options

[spdf]

JAXA wants to continue with Hayabusa 2. However there is/was a huge fight about the budget. Main problem was the budget for the launch vehicle. 2 months ago or so there was a report which said, that JAXA had to find another launch vehicle or the project gets cancelled. Now the Italian space agency played saviour and overed the VEGA. So finally we might see another Hayabusa in 2011.


It was mentioned here:
http://www.jspec.jaxa.jp/080110Final_IPEWG-ProgramBook.pdf

[Paolo]

high resolution pics are on JAXA digital archive
http://jda.jaxa.jp/category_p.php?lang=e&a...mp;page_pics=50

[pandaneko]

high resolution pics are on JAXA digital archive
http://jda.jaxa.jp/category_p.php?lang=e&a...mp;page_pics=50

Thanks, Paolo

I also found an intersting article, which I have translated as follows. Its origin is given at the top of my translation. In it, P stands for pictures and G stands for graphics. Some of these are actually texts and they are too small to be properly recognied, so I have not translated these.

Here it goes, from P

http://news.mynavi.jp/articles/2012/12/28/...usa2/index.html


JAXA demonstrates Hayabusa-2 flight model to the press

On 26 December JAXA displayed the flight model currently under construction at its Sagamihara campus (ISAS campus). It is a succesor to Hayabusa which landed on
an asteroid caIled Itokawa and returned to Earth in June 2010. It was shown to the press at the time when only its main body frame and solar pannells are complete.

P-1:　Hayabusa 2 shown here. It looks very different from its final form of completion.
P-2:　This a 1/20 scale model. A cylindrical device shown in the middle of its body is the impacter.


Another point of difference is its increased length (or height)

Hayabusa 2 measures 1.0mx1.6mx1.25m and weighs 600kg including fuel. As its predecessor it is intended to carry out a sample return mission. Launch timing of December
2014 is assumed. If successful it will return at the end of 2020.


The model shown this time is the completed body frame with its solar pannels plus dummy weight components. Dummy weights are attached to ensure same weight
and same centre of gravity during the vibration tests currently being conducted.


P-3: Shown from behind the probe. Body and solar pannels are flight ready. Main body is composed of 8 alminium honeycombe pannels (6 outer and 2 inner pannels).
P-4: Holes are meant to hold iron engines. Shown in front is the dummy iron engine weight and fuel tank dummy weight is seen at the end of the hole.


P-5: A pipe like object is seen sticking out. This is a dummy middle gain antenna.
P-6: Seen from the left. 3 solar pannels per one wing are folded and obstructing the view of the side of the main frame.


P-7: The device with an ambrella like object is the sampler horn. This sampler horn also is a flight model. A cylinder shown in front is the sase for Minerba 2
(mini-rover)
P-8: Sampler horn seen from the other side. Since three minerba 2 rovers will be on board there is also another cyliner on this side.


P-9: We could not get the front view of of the main body. Dummy weight of the return capsule is only just shown here.
P-10: The model is placed on the vertical vibration tester. Red cable leading from the probe is for acceleration sensors. In front is the horizontal vibration
test bed.


Main points of difference from Hayabusa are as follows.


G-1: On board device comparison (1)
G-2: On board device comparison (2))


Conspicuous in its external appearance is the two high gain flat antennas in place of the usual parabolic antenna. Of these one is intended as with Hayabusa for X-band
(7-8 GHz) range, but the other one is for Ka band (32 GHz) range to ensure higher comms. speed and to secure higher degree of redundancy.


Vital to the return journey is the fuel efficient iron engines. Same number of four engines will be on board. However, propulsive power of each unit has been
increased from 8mN to 10mN.

New device that attracted our attention is the impacter. This device will accelerate a 2 kg copper collider (liner) to a few km velocity by explosion of an explosive
and collide with the asteroid surface, creating an artificial crater of a few meters in diamter. This will make it possible to sample prestine inner materials not
affected by solar corrosion.

There is no significant change made to the sampler horn. One small change is the nails added to the inner surface of the horn tip in order to increase the amount of
samples. The number of projecter has been increased from 3 to 4. Sample containing room is now divided into 3 sections (previously 2 sections).

With Hayabusa there was only one mini rover called Minerba which faild to land on Itokawa. With Hayabusa 2 there will be three of these of similar size and these will
be collectively called Minerba 2. In addition another small lander called MASCOT developped in Europe will be on board.


Hayabusa was intended for sampling from an S type asteroid. Hayabusa 2 will ber flying to a C type asteroid 1999JU3 where existence of organic materials and water
is expected. As a result observation devices will include a near infrared spectrometer and mid infrared camera. Of these Hayabusa did have a near infrared spectrometer,
but observation range has been changed so that water absorption band can be seen.

Main body frame looks similer in size, but it is longer by 15cm in the height direction. Its weight is also heavier bby 100kg in order to cope with the increased
number of devices.

2 years to launch, no time to loose

Expected launch timing is December 2014, but if JAXA fails to make it next launch timing will be 10 years later, making continuiation the whole project impossdible.

Sample return from type C asteroids will be scientifically significant. However, many of them exist in the main belt between Mars and Jupiter and they are
too far from here and Hayabusa class probes will not be able to cope with the mission. 1999JU3 just happens to be in near earth orbit, making it about the only type C
asteroid.




G-3: With Hayabusa 2 there are 3 points of significance
G-4: Mission scenario is different



G-5: Selection of target asteroid. 1999JU3 has been selected.
G-6: With 1999JU3 we still do not know its exact shape.


Project manager, Prof Hitoshi Kuninaka of JAXA (ISAS) stresses emphatically that they will to stick with the launch in December 2014. Theoretically speaking,
there are windows in June and December of 2015. However, arrival timing of June 2018 cannot be moved and the delayed launch will mean that much harsher operation
of iron engines.





P-11: Hayabusa 2 project manager, Prof Hitoshi Kuninaka. He was in cgarge of iron engines with Hayabusa.

December 2014 launch means 80% operation rate. However, the launch in Decmber 2015 will require 96% operation rate, meaning rest time of only 7 hours per week.
Communication with the earth station alone will require 5 to 6 hours and that means almost limiting conditions in case of troubles.

Right now, Hayabusa 2 is located at the Sgamihara campus of JAXA (ISAS), but very soon after the year end 2012 it will be transported to Tsukuba Space Center
to undergo accoustic tests. It will then be returnd to Sagamihara in mid January 2013 to undergo electricl tests and other component tests. Then, from October
2013 its final configuration will start, to be flight ready by summer 2014.

[TheAnt]

I also found an intersting article, which I have translated as follows.....

Thank you for yet another update pandaneko, appreciated. =)