Here is a movie about the Ikaros. It is a bit long, but it should give you some idea.
http://www.youtube.com/watch?v=7_6HOqBkP2o
Pandaneko
Akatsuki and IKAROS about to be transported to the VAB for mating to H-2A rocket
http://twitter.com/ikaroskun/status/13593614219
And here are photos showing the aluminum plates containing 63,248 names and a Planetary Society-provided DVD containing 89,000 names (that were submitted online between December of last year and March 22) being installed onto IKAROS
(We don't seem to have a dedicated IKAROS thread, so...)
JAXA set to launch a solar sail technology demonstration mission:
space.com article: http://www.space.com/businesstechnology/japan-venus-double-mission-100516.html
IKAROS has been spun up to 25 rpm in preparation for sail deployment within the next few days.
The counterweights that will draw out the sail masts have been deployed (see pictures in http://www.jspec.jaxa.jp/ikaros_channel/bn004.html
Now(6/5 0:54 JST) IKAROS is drawing out the sail by the centrifugal force.
The sail is still bundled.
Please refer to the animation below URL.
The bundled sail has been extended to the opening drawing out passing about 10m.
It is a state of about 35 seconds of this animation now.
http://www.youtube.com/watch?v=7Mb47w0vB04&feature=related
http://www.isas.jaxa.jp/home/IKAROS-blog/?itemid=549
----from IKAROS blog (japanese) , translated by akibow-----
Japan Aerospace Exploration Agency (JAXA) operated IKAROS (launched from Tanegashima Space Center on May 21, 2010(JST) until last night, and normally ended the second day of first-step of sale development.
However, there were some differences between the flight result and the simulation about development.
For more careful second development, we decided to examine the numerical value closely.
Therefore, the third day of first development and the second development is scheduled after Tuesday, June 8(JST).
We will announce schedule of the third day of first development and the second development as soon as we decides it.
The state of the explorer is excellent.
http://twitter.com/ikaroskun
----from IKAROS twitter (japanese) , translated by akibow-----
I'm telling many information to USUDA antenna.
They say that my movement is different from the simuration in pre-launch.
I am safe and energetic though movement seems to be different.
Argh. Thanks very much, Akibow.
The IKAROS team is going about the deployment slowly & cautiously, and that's eminently sensible. It's gonna be done right!
related article.
http://www.planetary.org/blog/article/00002527/
http://www.isas.jaxa.jp/home/IKAROS-blog/?itemid=550
---translated by akibow---
TODAY'S IKAROS (6th,June)
IKAROS stands by with maintaing first development, length=5m or more.
Under this condition, the spin rate is increasing very slowly.
This is anxious for the developer of IKAROS , though is not an amount that becomes a problem.
it is the one about which it is anxious in a small symptom though it is not an amount that actually becomes a problem on because it is very slow.
The cause is not specified yet.
Many reasons are thought.
For instance, it is accelerated the rotation by the sunlight pressure like the pinwheel,
or an influence of the out gas or might be the one more by another factor.
We obsere this phenomenon by using this standby time. (Y)
6/6 IKAROS
Distance of the sun:1.04AU
Distance of the earth: 6,342,032km and right ascension =- 157.8° and celestial declinations =- 23.0°
Distance of Venus: 1.25AU
Posture: 7.4 rpm and spin rate = sun corner 15.0deg
my impression is that IKAROS, in its current semi-deployed status is just spinning up like a propeller due to solar radiation pressure, which in itself would be proof that the sail is working
http://www.isas.jaxa.jp/home/IKAROS-blog/?itemid=551
---- summary ---
Japan Aerospace Exploration Agency (JAXA) will execute the third day of first developnent and the second development.
June 8th evening-midnight (JST) : 3rd day of 1st development + 2nd development
June 9th evening-midnight (JST) : confirm development
second development is full expansion of sail.
http://www.youtube.com/watch?v=7Mb47w0vB04...feature=related
Sail Deployment Schedule for IKAROS
(SUCCESSFUL) June 2 (Wednesday) evening - midnight: pre-deployment check sail (motor and commissioning)
(SUCCESSFUL) June 3 (Thursday) evening - the night: the early development of first stage sail deployment
(SUCCESSFUL) June 4 (Friday) evening - midnight: Day 2 Official first stage sail deployment
June 08 (Tuesday) evening - midnight: Day 3 Official second (and final) stage sail deployment
Tuesday, June 09 (Wednesday) evening - midnight: Review of second stage sail deployment
http://www.isas.jaxa.jp/home/IKAROS-blog/
Another fascinating mission from JAXA :-) Hope it all goes well.
Can anyone tell me if it is planned to put IKAROS into orbit around Venus? Is it possible?
Or will there be a flyby?
Is there any information available about how much force/acceleration the sail experiences due to solar wind and radiation pressure?
Thanks and regards,
Brian
See here for an interesting idea
http://www.unmannedspaceflight.com/index.php?showtopic=6508&view=findpost&p=160641
Believe it or not, the Guardian is correct.
IKAROS will deploy a small free-floating camera once its solar sail completely deploys (which hopefully already happened) to photograph the spacecraft in all her diamond-shaped (or square-shaped, depending on your POV) beauty... I gotta check online to see if it has a second camera onboard that it could deploy once it reaches Venus.
To have a wide shot of IKAROS in deep space, with Venus in the background would be one of the coolest space images, ever.
Lou said in an http://planetary.org/blog/article/00002523/ that IKAROS does have two deployable cameras. I assumed both would be used right away to observe the sail after deployment. How close will IKAROS actually get to Venus? Any camera with a wide enough FOV to take in the deployed sail would probably only see Venus as a pretty small (and unbearably bright) light source, right?
Yup, particularly the unbearably bright part. Remember the automatic exposure control on LCROSS' live camera and the Moon isn't even that bright.
Not sure how to interpret it, but at the IKAROS twitter (translated with Google translator), IKAROS reports having been too tired to concentrate, and will try again tomorrow.
I saw that, but thought it just meant that it was the end of a long day of work. IKAROS only communicates through Usuda, so there's a window of time very late in the day Japan time when they do all their work. I interpreted that just as IKAROS signing off for the night.
That being said, I spoke with Lou Friedman on the phone a couple of hours ago and he said he wasn't sure they really commanded the final stage of deployment last night. I won't be really confident it happened until I see pictures.
Second stage sail deployment is scheduled to take place tomorrow...while IKAROS completed the full first stage deployment today
http://www.isas.jaxa.jp/home/IKAROS-blog/
Hum, the latest (6/9 @ 17:33) post on the blog indicates a fouled tether. (I think)
The planetary society blog has a http://www.planetary.org/blog/article/00002536/.
A google translation of the most recent IKAROS blog post.
Here's a much better translation of that photo caption, provided by Lionel Ward:
From the IKAROS blog via Google translator.
Success.
From the IKAROS blog.
Emily http://www.planetary.org/blog/article/00002541/ that the sail is fully deployed & IKAROS is power-positive; congratulations to the project and to JAXA!!!
This is truly historic; a pioneering first by any standard. Can hardly wait to hear how he (is IKAROS a he?) performs during his shakedown cruise!
All that needs to be done now is for IKAROS to deploy those two free-floating cameras and photograph the sail in all its beauty
Can't wait for the images from the free floating cameras.
Looking at that diagram above, it looks like the deployment-view cameras overlap, but it's a bit hard to find anything to match up in each image.
Rather than fudge it, here's a foreshortened polar view created from the four sail-deploy images with no overlap attempted.
I hope they deploy that free-floating camera soon. Totally looking forward to seeing IKAROS in all its kite-shaped beauty
http://www.isas.jaxa.jp/home/IKAROS-blog/index.php?itemid=595
Anyone notice the IKAROS twitter profile pic keeps getting sadder and sadder? It's practically crying a flood now. Hilarously cute.
Why would it be getting sadder? Is something not going well???
Maybe it's getting sadder 'cause it knows that brother Hayabusa most likely doesn't have any samples inside its capsule. I kid.
Mmm...close! According to my wife, the latest tweets are an imaginary conversation between IKAROS & Hayabusa (messages of encouragement for the latter.) Guess the tears are for Hayabusa-san's impending EOM.
IKAROS has stopped crying...while Akatsuki has been smiling the whole time. Must have had a beef with his older brother.
Looks like the first of two free-floating cameras (DCAM 2) will be deployed from IKAROS today
http://www.isas.jaxa.jp/home/IKAROS-blog/?itemid=629
And the IKAROS Twitter avatar is happy again.
Seems free-floating DCAM2 has been released and the camera twitters here: http://twitter.com/DCAM2
Heh, Ikaros and DCAM2 are twittering about imaging.
Darn it. For some odd reason my Google toolbar won't automatically translate the DCAM2 Twitter page
Great picture of the fully deployed sail http://planetary.org/blog/article/00002552/ (in case there's anyone at umsf.com who doesn't check Emily's blog several times a day.)
Are there any specs on how long the camera is expected to remain within wireless range? And what's the plan for the second camera? I like punkboi's suggestion of "a wide shot of IKAROS in deep space, with Venus in the background."
TTT
I've been wondering how long they'll stay near IKAROS as well. Also, do those things have some sort of attitude control? Can't figure out how they made sure that IKAROS stayed in the camera's FOV unless it was very precisely ejected.
Naw, the cameras don't have attitude control... They're gonna drift off into deep space after being released from IKAROS. Check out the Youtube link below... The DCAM floats off in a spiral fashion after it is ejected from IKAROS...which would explain why the spacecraft is off-center in the image (which I'll provide below...despite Tom helpfully providing a link to the TPS blog )
http://www.youtube.com/watch?v=7_6HOqBkP2o&feature=player_embedded
Oh, okay, I get it now: The camera's actually spin-stabilized upon ejection. Thanks, PB!
Hi Brian,
I am not involved with the project myself, so someone should confirm the following:
If IKAROS is following (more or less) the same trajectory as Akatsuki, then it is not possible to insert in orbit around Venus.
The problem is that, although solar sails can in principle affect "large" changes in their speed (DV), they cannot do so quickly.
They are a bit like ion drives in that respect: they thrust gradually but continuously. To go into orbit around a planet,
you would need to gradually modify the sail's orbit around the sun using the solar radiation pressure force (SRPF)
until it is essentially identical to the planet's. I would imagine that, SRPF being quite flimsy a force, that process will take many years.
By the same token, however, the sail should flyby Venus at around the same time as Akatsuki enters orbit, probably at a distance
of several hundred thousand km or more. It could also be maneuvered to encounter near-Earth objects (asteroids or comets)
although I imagine that, for now, the technology demonstration objectives take priority over any other activity.
Regards,
Tolis.
Hopefully some kind person here will be willing and able to explain how IKAROS is going to be able to maneuver using its LCD panels. I understand that by darkening and lightening the panels IKAROS can increase or decrease the light pressure (terminology?) thus increasing or decreasing its thrust in relation to the sun. I also understand that, depending on its angle in relation to the sun, it can either slow or accelerate in relation to its orbit. What I have a great deal of difficulty envisioning is how it can change its attitude, pitch and yaw if you will. Given that the satellite has to rotate to maintain rigidity how can the LCDs modify its angle to the sun? Can they modify its rotation rate?
This is just a complete guess, but I would think that they could control the LCD panels on different sides of the sail independently. Darkening/lightening the panels on one side would provide a torque that presumably would change the orientation of the sail to the Sun.
Hello,
I once found one abstract on the project page telling that it is indeed possible to change the rotation rate via the solar pressure on areas of the sail, or better that it will be part of the experiment to verify this technique. The idea behind that it not "simply" brightening and darkening of areas, but to switch between diffuse and specular reflection.
I also have one question (because the google translation of Japanese leaves me quite clueless):
Is there a difference between the 2 DCAMs (something about 'separate antennas' and 'only one has a receiver' comes out of google's translation attempts)? Has only one been deployed so far?
source: http://www.jspec.jaxa.jp/ikaros_channel/bn006.html
I also came to that conclusion. But would that mean both have been deployed?
Thanks punkboi, Schillrich, ugordan, and fredk, it becomes clearer to me now. IKAROS is a remarkably dynamic craft and I hope we get some detail on how its trip goes.
IKAROS' spin rate has decreased from 2.5 rpm to 1.1 rpm to allow better stability of the sail membrane as it gets tested for attitude control
http://www.isas.jaxa.jp/home/IKAROS-blog/
Actually I understand it that way that it was decreased in order to allow attitude control experiments by reducing the angular momentum of the spinning craft.
Heh, that's what I meant. I worded it wrong
Hm. I thought DCAM1 was already jettisoned... I guess not
http://www.isas.jaxa.jp/home/IKAROS-blog/?itemid=646
Since IKAROS is spinning at only 1.1 rpm, I would assume the deployment of DCAM1 will be much more stable than that of DCAM2...and that IKAROS will be better framed (much more centered) in the DCAM1 images this time around
Thanks ngunn, norm and Tolis (and everyone else) for the great info. Sending IKAROS to Apophis (via one or more flybys) is an interesting idea. I have a hunch that it could be possible for an IKAROS type spacecraft to be captured by Venus or maybe Mercury (solar sails work better closer to the sun - not so good for outer solar system). Someone must have studied this possibility, I'll see what I can google. It would also be interesting to get some idea of the numbers involved regarding possible acceleration, dV, etc.
The complexities involved with attitude control of a (slowly) spin-stabilized flexible sail attached to a rigid "hub", using two different methods (hub thrusters / sail variable reflectivity), are fairly mind boggling. I can imagine the whole thing starting to "ripple" like a flag in the wind, or even just wrap itself up into a ball, if you don't do it right!
Amazing stuff.
Thanks and regards,
Brian
From what I understand of the Google translation of the IKAROS blog http://www.isas.jaxa.jp/home/IKAROS-blog/index.php?itemid=647 it appears that the second camera pod is released today. It is to be jettisoned at a slower relative speed (details of the separation system and separation speeds anyone?) to conduct a longer imaging session from a closer distance.
Anybody knows also how long are the DCAM batteries supposed to last?
I would imagine the batteries last far longer than the RF link budget between DCAM and IKAROS can last.
A previous IKAROS blog stated that the DCAM batteries...at least the one for DCAM2...is designed to last 15 minutes
15 minutes of fame
First picture from DCAM1 released! http://www.jspec.jaxa.jp/ikaros_channel/bn007.html
from much closer to IKAROS than DCAM2
According to today's blog post (6/22) they are adjusting the spin rate to "The spin rate will be selected to operate at optimum balance with light pressure" and they are seeking the optimum spin rate (now at 1.4 rpm). Also the GAP experiment is being activated under the charge of Kanazawa University.
DCAM1 images finally released
http://www.jspec.jaxa.jp/ikaros_channel/bn009.html
To continue this line of thought:
What is the possible ultimate fate of Ikaros? Is there a maximum communications range?
Can the inspection camera be also used to image asteroids or comets during a fly-by five or ten years from now, or are they only in the jettisoned pods?? We can still do radio occultation science.
Can it achieve solar system escape velocity?
http://www.jaxa.jp/index_e.html
July 9, 2010 Updated
IKAROS: Acceleration by solar sail confirmed
The small solar power sail demonstrator "IKAROS," which successfully deployed its solar sail, was confirmed to accelerate by solar sail receiving solar pressure.
This proved that the IKAROS has generated the biggest acceleration through photon during interplanetary flight in history.
There's much more info in the http://translate.google.com/translate?js=y&prev=_t&hl=en&ie=UTF-8&layout=1&eotf=1&u=http%3A%2F%2Fwww.jaxa.jp%2Fpress%2F2010%2F07%2F20100709_ikaros_j.html&sl=ja&tl=en (Google translate link)
At last a release in English: http://www.jaxa.jp/press/2010/07/20100709_ikaros_e.html
Meanwhile, IKAROS is also doing some science. http://www.jaxa.jp/press/2010/07/20100714_ikaros_j.html(in Japanese) about the first gamma-ray burst detection
Some gems about the possible future of IKAROS from The Mainichi Daily News http://mdn.mainichi.jp/mdnnews/news/20100718p2a00m0na012000c.html
Apparently the solar radiation pressure attitude control experiment was successful! we have a true solar sail out there!
release (in Japanese only at the moment): http://www.jaxa.jp/press/2010/07/20100723_ikaros_j.html
Solar Distance : 1.05AU
Earth Distance : 26105537km, ascension =- 141.2 °, declination =- 26.2 °
Venus Distance : 0.75AU
Attitude : spin rate = 1.5rpm, sun angle 22.4deg
For the last few days IKAROS was spun back down and the solar angle increased as JAXA continues to investigate sail trimming. Experiments in ranging are on going and increased emphisis is being given to acceleration. Since the 24th of July all attitude control is being handled by the RCD (LCD panels), a truely stunning breakthrough in propellantless deep space navigation.
According to this animated image, IKAROS will arrive at Venus on December 18 (Japan time)...11 days after Akatsuki does
http://twitpic.com/2g57yr/full
8 / 26 IKAROS
Solar Distance : 1.00AU
Earth Distance : 31401035km, ascension =- 130.8 °, declination =- 28.0 °
Venus Distance : 0.48AU
Attitude : spin rate = 1.3rpm, sun angle = 26.0deg
IKAROS has crossed Earth's orbit and is headed Sunward. The last few weeks have seen experiments with rotation rates going up to 2.0rpm and back down and sun angles reaching as high as 32.2 degrees.
From punkboi's post above it appears that IKAROS will be passing Venus on the "outside" as would be expected since it has been increasing its orbital speed since deployment.
I actually just sent an email to a Japanese contact about this today. I can't quite figure out what these updates mean. I'll post a blog entry if I learn anything.
Aha, it's not as bad as it seems. The problem is that Earth is passing through the sail plane, which is apparently a blind horizon for radio comms. Once Earth has gone through the sail plane to the other side, comms should resume. Today, Earth is within 13 degrees of the sail plane. IKAROS is being configured for autonomous operation during the communications blackout.
Thanks Ms. E.
I was pretty sure that things weren't as bad as my worry wart self thought but my confident self just could not sort out the good data from the noise.
(Nice rant today BTW)
The October issue of the French magazine "l'Astronomie" (http://www.saf-lastronomie.com/revue/index.html) has a very interesting article on a French radio-ham who managed to receive the signal from Ikaros during June using a 3.5 m parabola.
unfortunately I don't have a scanner at hand...
Good old Amatuer DSN guys. There's a ham radio group in Germany with a dish that would rival the smaller dishes of the DSN itself.
A report by the French radio ham is http://f1ehn.pagesperso-orange.fr/pages_radioastro/Images_Docs/IKAROS.pdf
IKAROS has spin up today. This is a very long time 2rpm.
A high spin rate, increasing the spin stiffness (as a frame) in space
Try to maintain a constant attitude.
Conversely a low spin rate will be strongly influenced by movements of the solar light pressure.
Adjusting the spin rate means that a balance of both to take advantage of this
I can do to change the direction of the desired position.
The IKAROS 10/18
Solar Distance: 0.84AU
Earth Distance: 28891627km, RA =- 132.6 °, declination =- 23.5 °
Venus Distance: 0.11AU
Attitude: spin rate = 2.1rpm, sun angle = 4.3deg
(Earth Distance 0.19AU)
Sun angle has been decreasing for several weeks now I wonder if they are "coming about" and reversing the "thrust" vector? One of the animations I saw seemed to indicate that might happen as they approached Venus.
The IKAROS 11/05
Sun Distance: 0.77AU
Earth Distance: 33318160km (0.22AU), RA=-146.5deg, Dec=-15.3deg
Venus Distance: 0.06AU (8975880km)
Attitude: Spin Rate=1.7rpm, Sun Angle=16.4deg
Blog entries are becoming sparser and apparently there are fewer communications periods as JAXA increasingly focuses on the Akatsuki Venus mission.
while Akatsuki was being recovered, IKAROS also flew by Venus last 8 December, some 80,000 km away
http://www.isas.jaxa.jp/home/IKAROS-blog/index.php?itemid=786
Interesting... I thought IKAROS wasn't suppose to pass by Venus till December 18
I am posing a very stupid question, I think...
Akatsuki has sped by Venus, right?, and IKAROS has done that, too? That means they are going in the same general direction. My question is this. Can they not direct IKAROS to Akatsuki and take a look at Akatsuki's nozzle skirt? After all, we have another 5 to 6 years.
As I am not sure as to what IKAROS's ultimate goal, I just thought that it can get closer and closer to Akatsuki. Does it have a telephoto lens, bet not...
With future missions we do need engineering cameras!!!
Pandaneko
They passed Venus at very different distances, which means that IKAROS (80000 km) would have been less deflected by the gravity of Venus during the fly-by than Akatsuki (600 km). Add to that that Akatsuki also performed the incomplete injection burn as it passed the planet. As a result, the two would have been on rapidly diverging trajectories after the Venus encounters.
In addition, Ikaros has only engineering cameras designed to monitor sail deployment. They're pretty low-res, and have a very wide field of view that would make getting a good view of Akatsuki very difficult. The danger of a collision between the two spacecraft would be too high.
OTOH, the thought of Akatsuki taking a self-portrait as reflected in Ikaros's sails is truly delightful! But will have to stay just a thought, alas.
Akatsuki should cast a shadow, having IKAROS close by would allow something for that shadow to fall on. You could just image that shadow. I would figure it could be done at a greater separation than would allow for Akatsuki to image its reflection.
You can't be serious H4I, Ikaros and Akatsuki are going to be thousands, probably millions of miles apart.
Oh I know. I thought it was understood we were just throwing ideas out there in a hypothetical situation.
I was thinking that it would make a great demonstration if Ikaros could be maneuvered to rendezvous with Akatsuki at some point during the next few years... but yeah: just tossing around hypotheticals.
IKAROS took this self-portrait with Venus in the background! (Darn it, JAXA... Release a larger size of this image)
Thanks to Emily for the heads-up: http://www.planetary.org/blog/article/00002892/
Based on @ikaroskun's tweets I'm pretty sure this is the largest size available -- if I am translating correctly, it took days or weeks to even download thumbnail images at IKAROS' current distance from Earth.
Here's a larger version of the IKAROS-Venus pic...taken from the JAXA press kit
http://www.jaxa.jp/press/2011/01/20110126_sac_ikaros.pdf
Mine was taken from the press kit too -- I think yours has more pixels but is just upsampled. Which is not to say that upsampling to make the image occupy more space on the screen doesn't help in interpreting the image; I just don't think it actually contains any more data.
What is to follow from now for some time is my translation of IKAROS report.
This is a strange report, for a start, it does not have an outline page, and secondly, and here, I am simply guessing from one abbreviated character string printed at the top right corner of this report that this report was comissioned to one person at JAXA, Dr Osamu Mori, and thirdly, its refrence number is 4-2, perhaps suggesting that there are other reports that JAXA do not carry on their regulaer web pages.
Anyway, the first page, page 1 goes like this.
Comissioned report 4-2
Report on the termination of the regular operation of the small solar power sail engineering test spacecraft.
26 January 2011 (Wed)
JAXA
Dr Osamu Mori
P
can't wait to read the rest of the translation! many thanks in advance Pandaneko!
Page 2: IKAROS report
0: Today's reporting items
We have been operating the small solar power sail engineering test spacecraft for the last 6 months, and we herewith confirm mission achievements based on the results so far and at the same time report on the latter part of the (continued) mission envisaged.
1: Mission objectives and significance
objectives
1.1 This is a front loading project for reducing the cost of development for the next project that we wish to run.
1.2 We wished to confirm the possibility of solar sailing and at the same time check on the power generation on the sail surface for the future hybrid propulsion system (no ion engines used this time)
IKAROS = Interplanetary Kite-craft Accelerated by Radiation Of the SunPage 2
P
Page 3: IKAROS report 4-2
1. Mission objectives and significance
The following 4 items are the main objectives
1. Large membrane expanstion (objective 1)
1.1 Extend a large 20 m membrane using the mechanism (similar) to be used with future spacecraft under zero gravity and in vacuum
1.2 Evaluate the extension mechanism and the result of expansion and relate the obtained data to analysis model
2. Power generation using the power sail
2.1 Generate power with the thin film solar power generator and confirm power generation through on-the-membrane harness
2.2 Obtain data of the generated power and evaluate characteristics
3. confirm acceralation by the solar sail membrane and check the obtained data agains the actual orbital measurement data (distance change rate by distance measurement data) (objective 2)
3.1 (there is something here, but I cannot read it, P)
3.2 Evaluate the acceralation capability and reflect the result into the orbital caluculation methods for reaching the target astronomical objects
4. Obtain navigation techiniques by solar sail operation
4.1 Confirm orbit determination techniques under solar acceralation
4.2 Confirm active control methods of photon acceralation direction vector by sail manipulation under photon pressure and obtain navigation techniques using the rsult
Objective 1: minimum success
Objective 2: full success
P
Page 4:
2: Result confirmation of mission requierments
(here, I do not wish to retranslate objectives carried before, so I will be brief with objective items as they are exactly the same, P)
2.1 Sail expansion:
complete, leading mass seperation on 26 May, primary expansion on 2-8 June, secondary expansion on 9 June and sail expansion was manitained after that by spin
2.2: evaluation
evaluation of spin and expansion and reflecting to expansion simlulation: achieved, we confirmed general agreenment between simulation and the real data obtained, and checked on the discrepancies and reflected them into the analytical model・. ,.
3: solar power generation
complete, on 10 June power generation was confirmed
3.1 interplanetary solar panell chracreristics evaluation, this was done once per week and compared with ground tested deterioration data<
HERE, I GIVE UP for this evening, because I thought that this page was a simple table page and that I could copy and paste and overwrite, but it is not that easy as its layout is messed up a lot. I will try again tommorrow.
P
Pandaneko, by all means please take your time...and thank you for this!!!
I will start from page 4 again. One thing that bothers me is that nowhere on this report submission it says submission was made to the Space Activities Comission (SAC) and the strange reference number, 4-2. I have a feeling that this is not an official report, rather internal, perhaps, and also interim, just to say, at this stage, something for the public at large.
Anyway,
Page 4 of the report 4-2 is as follows (this is a 30 page report)
2. Confirming results of the mission requests
1. Expansion of the large area membrane
1.1 Expand the 20 m (diagonal) membrane in vacuum and under zero gravity using the mechanism similar to that to be used with future space probes.
Completed: (I will come to definition at the end of this page, P)
Leading mas seperation on 26 May, primary expansion during 2-8 June, and final expansion on 9 June, and after that expansion was spin maintained
1.2 Evaluate expansion behaviour and expanded status and reflect the findings into the analytical model for expansion simulation.
Achieved: (I will come to definition at the end of this page, P)
We confirmed that observed expansion behaviour was more or less consistent with our prior simulation. We also evaluated discrepancies and refelected them into the analytical model.
2. (this 2 is within the header 2. that is, subsection 2, P) Power generation by the solar power sail
2.1 Generate power with the thin film solar power generation system, through the membrane harness, and confirm it by IKAROS itself
Completed:
power generation was confirmed on 10 June
2.2 Obtain relevant data of the solar cells on the membrane and grasp their characreristics
Achieved:
We conducted about once per week evaluation and compared the data with predicted deteriooration curve and grasped the characteristics
3. Confirm acceralation by the solar sail
3.1 Confirm solar sail's acceralation effects by orbit determination (measued distances and distance change rates)
Completed:
We observed photon induced acceralation and confirmed that the resultant propulsion was within the designed values.
3.2 Evaluate acceralation ability and reflect obtained data into the orbit determination methods for reaching target astronomical bodies
Achieved:
Optical characteristics were inorporated into the attitude orbital dynamics and established the optical method for parameter determination
and refelected those into the orbit planning system
4. Obtain navigation techniques with the solar sail
4.1 Confirm orbit determination techniques under photon induced acceralation
Achieved:
We have built a photon induced acceralation model and established the orbit detemining method including tracking, and actually operated the model with IKAROS.
4.2 Establish active control methods for photon induced vector treatment by the sail and the navigational techqniques by using those control methods
Achieved:
We confirmed that we can achieve required and planned orbit control by active sail attitude manoever. We conducted this relative to Venus and are satisfied with the results.
Glossary:
Achieved: mission requests jhave been more or less met and addtional analysis (including data from continued operation) may lead to further results
Completed: all of mission requests have been met perfectly
P
Page 5:
2: operational procedures and confirmed results against mission requirements
(on the diagram) red blacket relates to the first few weeks in search of a minimum success, whch is the extention of the membrane and power generation and the blue bracket relates to the following 6 months in search of a full success, which is to verify the acceralation by the sail and to gain navigational skills
(Here, character strings are numbered from 1 to 5 and these are)
1. launch (21 May) and spin seperation of the craft (5 rpm)
2. initial checking and spin-up (25 rpm)
3. solar sail extension (2.5 rpm, 2-9 June), power generation on 10 June, and spin rate adjustment (1-2.5 rpm)
4. acceralation by the sail (9 July)
5. orbit control and navigation skills (December 2010)
Page 6:
2: Membrane extension (attitude data)
1. leading mas seperation on 26 May, primary extension during 2-8 June, and final extension on 6 June. Extension mechanism wroked well and spin behaviour was more or less consistent with expectation.
2. Departing camera was used on 14 and 19 June and captured the sail image and confirmed no anomaly.
(there are 3 graphs here, from left to right, and these are)
1. leading mas seperation
2. primary extension, and
3. start of final extension
With these graphs vertical axes on left are the spin rate around Z-axis, and that on the 3rd graph on the right is the angular velocity (red for X-axis and blue for Y-axis)
Page 7:
2: sail extension images
There are 6 images here, those on left were taken by the engineering camera on board and those two on the right were by the departing camera.
4 captions for the engineering camera, clockwise, are:
1. after leading mas seperation
2. during primary extension
3. after final extension
4. after primary extension
The caption for the departing camera images is "confirmation of liquid crystal device", ON is specular reflection and OFF is diffuse reflection
Page 8:
2: Power generation by the sail
We conducted a verification test on 10 June, followed by about once/week of characteristics evaluation and confirmed that the data was more less consistent with the predicted values obtained on the ground.
There is one table and one graph here on this page.
The header row for the table at top, from left to right says;
number, membrane section measued, Isc, Pmax, Imp, and temp
The second row has only one character string and that is the predicted value.
With the graph on right the caption on top is I-V characteristic.
These measurements were taken at 22:50 on 10 June, 2010, at 1.05 AU, earth distance of 7860133 km, sun angle at 13 deg, spin rate at 2.5 rpm.
Pandaneko
Page 9:
2: Verification of photon acceralation
2.1 We confirmed photon acceralation by Doppler measurements.
2.2 Estimated propulsive power was in agreenment with the designed value.
2.3 We measured photon proplusion at different AUs and at different sun angles. Cumulative photon acceralation reached 100 m/s.
(2 graphs here)
One on left is the Doppler measurement history.
Vertical axis on left is the difference of IKAROS between two cases where photon pressure is present (actual measued values) and where photon pressure is absent (calculated values) in mm/s.
Horizontal axis is the time line around the final extension on 9 June 2010.
The caption at the bottom of this particular graph says "Estimated (from Doppler effects) photon pressure= 1.1 nM"
There are chrracter strings on this graph, top one says "execution of final extension at 09:36 UTC" and the one below it says "time region where data is missing due to swtich over to oneway Doppler mode".
The other graph on the right is the cumulative photon acceralation, vertical axis on left is just that, horizontal axis is the time line between 22 May and 8 December. The caption at bottom of this graph says "We achieved 100 m/s by November".
Page 10:
2: Navigational skills obtained with the solar sail
2.1 With the liquid crystal device we conducted device checking and attitude control experiment and confirmed that expected control ability was achieved.
2.2 IKAROS flew by Venus at 80,000 km on 8 December and it was a day later than AKATSUKI because we conducted a non-balistic flight by the solar sail on way. Akatsuki was led to the sun side of Venus and IKAROS to the night side.
(with this page 10, we have 2 graphs and one image)
With the leftmost graph the vertical axis is the sun angle (its title is the spin rate during control mode, by the way) and the horizontal axis is the time line in UST, starting at 12:00 on 12 July.
The character string in the top box is "control start", bule dots are before the start of control mode and red dots are taken during this control mode operation. Solid line is the expected sun angle without control.
The chenck of caption below it says" gievn the initial evaluation which took into account the sun distance and the sun angle we confirmed that over 90% of attitude control accuracy was achieved".
The second graph is as follows.
The character string in red at top says "nearest approach to Venus at 07:39 UT and IKAROS is moving to the left.
Then, the image, and this is before image processing.
(To me, it does not look fully extended. It looks like a dried jelly fish thrown up on a beach..., P)
Page 11:
3: Outline of follow-up operations
3.1 duration: until about end March 2012 (and we will be making a decision on further follow-up operation at that time)
3.2 DSN station: Usuda 64 m
3.3 Objectives:
We wish to gain further insight into solar sail navigation which we hope will contribute to the development of next project.
3.3.1 Solar power sail mission: 4 new themes and 3 continuing themes
3.3.2 With optional devices (GAP, ALDN, VLBI) current mission will continue
3.3.3 Evaluation of newly developped devices, such as liquid/gas equilibrium thruster, MGA, mission system electicity
PANDANEKO
Page 13:
3: Continued mission plan (themes related to the main mission)
3.1: large membrane extension
Continuation theme 1:
Evaluate the extended state and check up on mechanical deterioration of the sail surface
New theme 1:
Proactively pull out the membrane behavoiur and shape changes and construct a dynamic model of the extendes state
3.2: Power generation
Continuation theme 2:
evaluate the capacity and monitor system deterioration
3.3: Verification of acceralation by the sail
Continuation theme 3:
Evaluate its ability and dependency on reflection characteristics and deterioration, and attitude dependecy on membrane shape during photon acceralation
New theme 2:
Improve, given membrane shape changes, the the seperation accuracy of photon reflection and areas concerend, and use the data to construct an optical parameter model of the membrane
3.4: Navigational skills:
New theme 3:
Make use of the increasing distance between Earth and IKAROS, to evaluate the orbit determination accuracy under photon pressure andacceralation
New theme 4:
Evaluate the long term control/guidance characteristics per each orbit revolution
NOTE 1: With all of these themes they are expected to be completed by 31 March 2012, and contribute to the next step in development for the project targetted at Jupitor and the Troia group of asteriods
NOTE 2: Mission included in the continuation plan should contribute to the studies of large membranes, orbit determination/control under solar photons. These will be useful for other purposes and projects.
Page 13:
3: Comments on new themes included in the continued operation
New themes 1 and 2:
These should contribute to the studies of large membrane structure.
We confirmed, from regular operation so far, that changes in sun angle and spin rate will lead to membrane shape changes and that solar photon pressure does contribute to membrane behavoiur.
With this in mind, we will proactively alter the combination of sun angle and spin rate in order to;
1. construct a dynamic model of the extended membrane structure
2. consttuct an optical parameter model of the membrane
New themes 3 and 4:
These will contribute to the studies of orbit determination and guidance under photon pressure.
Given increasing changes in the relative positions of Earth and IKAROS compared with those during the initial regular operation we will make use of them in order to;
1. evaluate orbit determination accuracy under photon acceralation (accuracy decreases as the distance increases)
2. Evaluate long term controlability (evaluate orbit info per every revolution around the sun)
P
Page 14:
3: Orbit plan (from launch to Venus)
launch: 21 May 2010
nearest approach to Venus: 8 December 2010
(There are 2 graphs here and this page must be self-explanetary, P)
Caption at the top of the left graph says "Nearest approach to Venus on 8 December 2010", and the caption at bottom is "launch on 21 May 2010". At the centre is the sun, Venus green, earth blue.
Caption at the top of the right graph is "Sun-Earth fixed system". At the centre is the sun and Venus green, and the character string just below IKAROS (in red) is the Earth
Page 15:
3: Orbit plan (from nearest approach to Venus to the end of fiscal 2011)
Black square: nearest approach to Venus on 8 December 2010
Black diamond: 31 March 2012
(There are 2 graphs here)
With the left graph the sun is at the centre and the caption at the top is "nearest approach to Venus on 8 December 2010"
With the right graph the caption at the top is "Sun-Earth fixed system", sun at the centre, Earth is the blue dot on the right, IKAROS movement in red.
Page 16:
3: Orbit plan (from fiscal year end of 2011 to the furthest point)
black diamond: 31 March 2012
black star: 6 December 2012
(There are 2 graphs here)
2 captions at the bottom of the lefthand graph, the left one says "furthest point on 26 December 2012" and the one on the right says "31 March 2012".
With the right hand graph, my earlier comments apply.
Page 17:
3: Operational policy for the latter half of IKAROS operation
Given the limited coms capacity our operational policy is as follows:
3.1 February 2011:
attitude/orbit determination (new themes 3 and 4, continuation 3)
confirmation of sail extension and power generation (continuation 1 and 2)
GAP operation and reproduction of ALDN observation data
3.2 May, June 2011:
attitude/orbit determination (new themes 3 and 4, continuation 1 and 2)
confirmation of sail extension and power generation (continuation 1 and 2)
reproduction of GAP, ALDN data, engineering experiment with VLBI
attitude/orbit determination upon changing spin rate and sun angle (new themes 1 and 2)
3.3 July 2011 and beyond:
We will make our judgement based on the results obtained by June.
Current tentative plan is as follows:
We are going to change the spin rate and the sun angle over a very wide range and;
1. If we can improve coms status we will try a longer operation by economising on fuel.
2. If we cannot improve coms status asa result we will still try to economise on fuel and try to maintain MGA's link attitude.
P
I now realise that I made a simple mistake with my earlier translation.
Page 17 should have been page 18. And Troia group of sateroids should have been Trojan group of asteroids, I think.
Anyway, page 17 should have been as follows, P
Page 17:
3: Latter mission operational plan
Continue with optional devices mission
1. GAP: GAP= GAmma‐ray burst Polarimeter
This device comprises of a refelector at the centre, surrounded by 12 pieces of fluorescent light detector, intended to measure polarisation of Ganma ray bursts.
2. ALLADDIN= Arrayed Large‐Area Dust Detector for INterplanetary Space
This device is intended to record collision occurence times, maximum signal value and signal decay so that data will contribute to spatial distribution analysis of space dusts in the region nearer to the sun than earth.
3. VLBI= Very Long Baseline Interferometry
This will make use of quasors in the far distance in order to measure precise IKAROS positions using delta VLBI technique. Regular measurements will be made with future missions.
Results so far of these optionnal devices:
1. GAP, ALDN, VLBI are all normal and producing data, however
2. because we concentrated our resources on system operation as the first priority we have not had enough time with these divices. So, our current intention is to use them as long as we could.
P
Page 19:
4: Supplementary information
What is the solar sail?
1. Solar sail: is a craft which makes use of solar photons for propulsion.
2. Solar power sail: is, in addition to the sail membrane itself, solar power generation devices are attached to the sail surface
If we combine ion engines and solar power sails we should be able to navigate into regions much further away from the sun. We will be trying out this idea with our next mission targeted at the Trojan group of asteroids and Jupitor.
P
Page 20:
4: Supplementary information
Significance of solar power sailing:
This is expected to lead to flexible operation of probes.
It is also expected to provide enough electrical power in the vicinity of Jupitor and beyond.
P
Page 21:
There are graphs and other structures with this page, but they are self-explanetary. So, my translation is only about IKAROS specs, as follows.
Main body size: 1.6 m in diam. and height 0.8 m
Membrane size:s 20m by 20 m, and membrane thickess of 7.5μm
Mass: 308kg, of this 16kg is the membrane mass
Orbit: direct flight to Venus
Orbit determination: range fidings and Doppler measurements
Attitude control: by spin
Propulsion: vapour and liquid equilibrium thruster and gas jet thrusters
Mission duration: longer than 6 months
Comms: 2 LGAs and 1 MGA
P
I will skip pages 22 and 23 as they are too obvious.
Page 24: Supplementary info on GAP
1. Small table header from left to right:
GRB name, trigger time, distance, alpha, beta, angle of entering, simultaneous observation
2. With the 3 graphs here vertical axis is intensity, horizonrtal time in seconds
Main text (jist of it) as follows:
GAP is a ganma ray burst polariser detector. It also achives simultaneous Compton scattering counting.
Power was switched one month after launch. Data is stored in memory and sent back to earth. No mulfunction to date. GAP detects polarisation of megnetic field.
P
Page 25:
4: Supplementary info on GAP
(Here, I am only translating gists of what this page says, P)
Primary objective of GAP is to measure polarisation of ganma ray bursts and try to understand the mechanism. However, it is only 4 months in operation and we have not yet meaure enough of these bursts.
Following report (what follows?, P) is based on the collaborative work with all those GRB satellites around the world with a view to determining the directions of these bursts.
Earlier page's list has data from Russian Konus satellie (K), US Fermi satellite (F), and US-Italy Swift satellite (S). For example, the burst, GRB 100826A (detected on 26 August 2010) was determined to be within the region surrounded by the blue frame with the graph here. Due to polarisation measurements IKAROS is providing additional accuracy.
P
Page 26:
4: Supplementary info on VLBI (multi tone transmitter)
Result of of experiments:
Succeeded in obtaining about 20 times more accuracy of orbit determination compared with earlier JAXA measurements (Hayabusa and AKATSUKI), with the thermal noise level of 50 pico seconds.
Objectives of the experiments:
This is a mission devoted to try out DDOR(Delta differential one-way range) techniques. Basically, very far radio emitting stars are used and the very long baseline interferrometry and triangulation is involved. Participants are as follows:
University of Tasmania: Hobart26m
DSN: DSS34 34m,DSS45 34m, DSS43 70m
ESA: Cebreros 35m New Norcia 35m
ATNF: Mopra 22m, ATCA 22m
Shanghai Observatory: Urmuchi 25m, Shanghai 25m, Konmei 40m
Japan, 32m, 34m, 34m and 64 m)
NASA JPL is quite active in this technology, and for instance, NASA DSN were deeply involved, when required, with DDOR determination of Akatsuki, almost everyday. Collaboration has been done before, but we lacked this essential element, multi tone transmitter, and this time we developped a dedicated transmitter and used it with 8 organisations' 15 antennas with 24 pases.
Comparison (orbit information) between Akatsuki and IKAROS data is as follows:
Akatsuki:
precision : (thermal noise) 700 pico seconds
accuracy : 1 to 2 nano seconds
IKAROS:
precision: (thermal noise) 50 pico seconds
accuracy: 50 to 150 pico seconds
This comparison was made around August 2010
P
What follows from page 27 on, I find it very difficult to translate (technical terms, mainly), but I will give it a try in the belief that even if my translation is not good some people with background knowledge may find them useful.
Page 27:
4: Supplementary info on VLBI multitone transmitter
We developped a DDOR digital base band converter (64 Msps/16 ch/4 bit, 4096 Gbps). 2 graphs here, one on left is the result obtained by this digital wideband system, and one on right is the data recorded by conventional analogue/narrowband system.
With conventional recording system you need to combine a couple of 8 MHz bandwidth analogue signals. The right graph indicates that the gain and the phase within the band are not flat enough.
With this new system it becomes possible to use weak qasor signals as calibrators and that will be useful with future wideband DDOR systems using Ka band.
Page 28:
4: Supplementary info on VLBI multitone transmitter
There is one graph on this page, which came from the observation made on 29 July 2010, using Usuda-Canbera baseline for VLBI observation.
Vertical axis is the delay residual (whatever it means, P) in nano seconds. Horizontal axis is the time ellapse from the start of observation in seconds.
Upperleft character string says "Lizzard constellation's star BL's delay residual"
Character string down right says "delay residual of quasor J1425-2513"
Character string to the left os it in blue says "delta DOR observed quantity"
The bottommost character string says "IKAROS delay residual"
There are 2 texts here on this page, the first one being explanation of the chart itself, and the second one is on future operations from now on. And, I am now going to paste those text down here for further translation. If it does not go well, then I will send this up anyway and try to upload another post.
On the graph, 6 groups of dots (I find only 5, P) relate to IKAROS' VLBI delay residual and those 3 upper left and another 3 upper right exists in the vicinity of IKAROS on the "star sphere surface" (I do not know the word for this, P)
These two are the delay residuals of the astronomical bodies whose positions are accurately known. IKAROS' plot is based on range/Doppler measurements and if its orbit determination is correct IKAROS' delay residual should be on the same line as these of two astronomical bodies'.
However, these are not in line, clearly suggesting a bias coming from orbit determination error not accurately estimated by range/Doppler measuments.
ΔDOR observation quantity: (-7.83 nsą50ps)
With these two astronomical bodies we see that , despite weak signals from quasor producing a lot of noise, delay residuals are on the same line, suggesting that bias due to the presence of atmosphere etc has been successfully removed.
Operations from now on:
Compared with bus system antennas VLBI transmitter has a narrower bandwidth and future observation oppotunities are limited and measurment accuracy is not large. However, we will continue to operate the system because we expect to be using this system with our future missions a lot regularly and we need to improve on the system such as pipelining and semi-automatic operation.
Observation so far has given us a lot of quality data for orbit determination and we should be able to come up with detrmination accuracy of a few centimeters, compared with a few meters accuracy required for deep space orbit determination.
We will also be making use of near Earth satellites for further improvements on accurate orbit determination.
P
Page 29:
4: Supplementary info on ALADDIN
ALADDIN = Arrayed Large Area Dust Detectors in INterplanetary space
Mission objectives:
Cosmic dusts detector engineering tests, to be used for future Jupiter exploration and other outer planets, also to be used in near Earth orbits.
Device composition and arrangement:
1. 0.3% of the sail membrane (0.54 square meters)
2. Piezo-electric thin film elements of 2 different thicknesses at 9/1000mm and 20/1000mm in 4 channel arrangement at the sensing part (ALDN-S at 40g) and detection part (ALDN-E at 210g)
P
Page 30:
4: Supplementary info on ALLADIN
Operational results:
1. Operation started on 21 June 2010.
All 8 channels detected cosmic dusts, more than 100 of them within the duration of acumulative 25 days startong on 30 June.
2. Study of distance dependency of cosmic dusts in the solar system
We are getting more accurate data by cumulative 24 hours of observation.
(End of IKAROS report, 4-2)
P
domo arigato gozaimasu, Pandankeo, I have really enjoyed your translation!
Thanks, Paolo
I am taking a little time off at the moment, but I will come back with the newsletter translations soon.
Since it contains different topics and since I do not wish to be a new topic starter I am thinking how best I might do this. However, I can assure you that these newsletters do make some interesting light readings.
While at work I always enjoyed these, and I would have thought they no longer existed...
P
just one question: what are they talking about when speaking of "1970", "1990" etc in page 30?
a good resume of the IKAROS missions, its technologies and its results so far (in English)
http://www.isas.jaxa.jp/e/forefront/2011/tsuda/index.shtml
Aviation Week is running more or less the same story: Jhttp://www.aviationweek.com/aw/generic/story_channel.jsp?channel=space&id=news/asd/2011/06/02/11.xml
Ikaros reversed its spin yesterday: http://www.jaxa.jp/projects/sat/ikaros/index_e.html
if I understand correctly today's release, IKAROS has been put into hibernation owing to the large distance from the Earth and Sun, making communication difficult and owing to the quasi-depletion of its reserves of gas for attitude control
http://www.jspec.jaxa.jp/ikaros_channel/bn018.html
pandaneko, can you confirm?
thanks pandaneko. there is also an English release at http://www.jaxa.jp/projects/sat/ikaros/index_e.html but it seems to lack some of the details of the Japanese version
The table in question is a regular matrix, 3 columns and 7 rows. Members are as follows.
C1R1: Item of evaluation.
C2R1: Before reverse spin operation
C3R1: After reverse spin operation
C1R2: Spin rates
C2R2: 0.17 rpm
C3R2: - 0.24 rpm
C1R3: Spin rate changes
C2R3: about 0.1 rpm (decreasing)/ day
C3R3: about 0.1 rpm (increasing)/day
C1R4: Sun angle
C2R4: tendency to increase
C3R4: tendency to decrease
C1R5: Sun-IKAROS distance
C2R5: 0.72 AU
C3R5: 0.72 AU
C1R6: Earth-IKAROS distance
C2R6: 1.10 AU
C3R6: 1.10 AU
C1R7: Remainning fuel
C2R7: about 2 kg or less (note: 20 kg at launch)
C3R7: reverse spin used a few hundred gramms of fuel
By the way, IKAROS is a kite and the kite in Chinese characters consists of a wind component and a width (or, span) component. I think it is lovely.
P
if you want to test your karaoke skills here, freshly released, is a IKAROS-dedicated song!!!
http://www.jspec.jaxa.jp/ikaros_channel/bn019.html
Science results from the ALADDIN dust monitor onboard IKAROS regarding the cosmic dust flux
in the inner solar system presented at 2012 LPSC:
http://www.lpi.usra.edu/meetings/lpsc2012/pdf/1632.pdf
Tolis.
if I understand the latest blog entry, IKAROS has responded to a command to switch on its transmitter last 6 September
http://www.isas.jaxa.jp/home/IKAROS-blog/index.php?itemid=1000
That's not how I read it; it seems to talk about "the search continues" and "why we keep looking" and the orbit info is "for reference only."
I hope pandaneko or someone else speaking Japanese can help
Paolo, it looks like I have to apologize; I think you were right. I'm asking for help translating this update:
http://www.jspec.jaxa.jp/ikaros_channel/
no need to apologize. great news indeed!
Thoroughly confirmed! http://www.planetary.org/blogs/emily-lakdawalla/2012/09102155-ikaros-alive.html
a release in English http://www.jaxa.jp/projects/sat/ikaros/topics_e.html
in fact Emily I think there is a small error in your blog post:
according to the latest blog entry http://www.isas.jaxa.jp/home/IKAROS-blog/?itemid=1002 reviving of IKAROS has been progressing slowly. they recently switched communications from the LGA to the MGA, which will probably mean that telemetry data should now start streaming at a much faster rate
http://www.jspec.jaxa.jp/e/hottopics/20130328.html
IKAROS project team disbanded. I am told that tracking support should continue
it looks like IKAROS was contacted again on 22 May
http://www.jaxa.jp/topics/2014/index_j.html#news2460
My wife's rough translation is that it's over 200 million km from Earth & hasn't been receiving enough solar power to operate; she used the word "sleep". Apparently in June it's expected to operate well enough to return (I assume) engineering data, but 7 months from now that'll be effectively EOM.
(Again, VERY rough translation; Kay wants to always state that she's got no background at all in space-related matters, and modern Japanese slang (esp. of the Net variety) is unfamiliar to her.)
Has anything more been said about the proposed late 2010s successor mission to Jupiter & the Trojan asteroids? Is that still planned?
and an English release: http://global.jaxa.jp/projects/sat/ikaros/topics.html
Just wondering... if Ikaros - like now - is still operating in early 2017, wouldn't it by orbital mechanics be doing another flyby of Venus at that point (10 Venus orbits or 7 Ikaros orbits after the Dec 2010 flyby)?
Ikaros has so far come out of hibernation during these perihelion phases, right (sometime around... now, this year)?
That might depend on the solar sail effect on the orbit - even if not intentionally 'sailed' during those orbits, the sail may have an effect, and the orbit may not be as straightforward as another spacecraft's would be.
Phil
http://global.jaxa.jp/projects/sat/ikaros/topics.html
signal received last April 23
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