IKAROS JAXA Solar Sail mission Options

[punkboi]

Heh, that's what I meant. I worded it wrong

[punkboi]

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

[BrianJ]

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

[Paolo]

From what I understand of the Google translation of the IKAROS blog http://www.isas.jaxa.jp/home/IKAROS-blog/i....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?

[djellison]

I would imagine the batteries last far longer than the RF link budget between DCAM and IKAROS can last.

[punkboi]

A previous IKAROS blog stated that the DCAM batteries...at least the one for DCAM2...is designed to last 15 minutes

[brellis]

15 minutes of fame

[Paolo]

First picture from DCAM1 released! http://www.jspec.jaxa.jp/ikaros_channel/bn007.html
from much closer to IKAROS than DCAM2

[Norm Hartnett]

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.

[punkboi]

DCAM1 images finally released

http://www.jspec.jaxa.jp/ikaros_channel/bn009.html

[pandaneko]

Great picture of the fully deployed sail here (in case there's anyone at umsf.com who doesn't check Emily's blog several times a day.)

TTT

I am not very surprised about this. About 15,16 years ago I was chatting to a prof at ISAS about the anntena opeinng of Halca space intereferometry satellite and asked him about the possibility. He simply flatly said that he would be extremely surprised if it did open up.

Apparently, he had seen it fully opended up at Mitsubishi's kamakura factory and never believed it will open up in space, but it did...

Second generation is going up in 2012, and what follows is some info on that.

http://www.jaxa.jp/pr/brochure/pdf/04/sat24.pdf

Of course, opening mechanisms must be different, I think. Halca anntena was built of very fine metal mesh, as I remember. Ikaros anntena must have been a lot easier to open up, I think. After all, it is a membrane, not a metal mesh.

Pandaneko

[JimOberg]

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?

[gwiz]

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?

From the images I've seen, the on-board cameras are wide-angle, not suitable for distant objects.

[punkboi]

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.

[elakdawalla]

There's much more info in the Japanese version (Google translate link)