Asteroid Itokawa shadow

keithsa · Post by **keithsa** » Wed Nov 16, 2005 9:00 pm

I seldom have cause to comment on your photo write-ups, but find I must for this one. The shadow captured on the Itokawa asteroid, upon closer inspection, can clearly be seen to be the Canadian flag. Perhaps it is not obvious as the photo is black and white, so the typical white and red colours are not evident, but it is clear enough. I think the journey to the commet, made secretly by the Liberal party here in Canada, is to be announced soon.

Thanks for your excellent work posting both this photo, and the multiple previous ones. I thoroughly enjoy your work.

Keith.

craterchains · Post by **craterchains** » Wed Nov 16, 2005 9:14 pm

uh huh, great post keith.

Two of the better Itokawa images I think.
Funny thing, No craters to speak of.

Norval

Doum · Post by **Doum** » Wed Nov 16, 2005 9:31 pm

LOL. Keithsa I see the same flag image. As for the asteroid, it look like it is very fragile due to its weak gravity (an aglutination of rocks 300 meter in diameter and barely holding together). it seem weak enought that it can collapse and disperse itself just by the effect of strong gravity of a planet if it came close to one. Can that asteroid be easy to destroy by a bomb if it were to come close to earth? Is it as fragile as it seem? And can it be thug?

FieryIce · Post by **FieryIce** » Wed Nov 16, 2005 9:39 pm

Doesn't that tag in the bottom corner of the flag say Made in Japan?

orin stepanek · Post by **orin stepanek** » Thu Nov 17, 2005 1:44 am

This asteroid looks like it has surface features that are not natural. Almost looks like flat surfaces and square corners abound all around. There is a large such area under and to the left of the [flag] shadow.
Orin

S. Bilderback · Post by **S. Bilderback** » Thu Nov 17, 2005 1:59 am

The indention looks like a slow elastic collision compressing the surface, but instead of the object adhering, it bounced off leaving its footprint.

orin stepanek · Post by **orin stepanek** » Thu Nov 17, 2005 3:52 am

I typed Itokawa into the Google and found the asteroid looks more like a potato. The square shapes must be from overlapping photos of the object.
Orin

craterchains · Post by **craterchains** » Thu Nov 17, 2005 4:56 am

Points up, those pictures may help the discussion.

Norval

S. Bilderback · Post by **S. Bilderback** » Thu Nov 17, 2005 1:45 pm

Doum wrote: it seem weak enought that it can collapse and disperse itself just by the effect of strong gravity of a planet if it came close to one. Can that asteroid be easy to destroy by a bomb if it were to come close to earth? Is it as fragile as it seem? And can it be thug?

Most non-metallic asteroids do break up when approaching a planet (as Shoemaker colliding with Jupiter), even more so when there is an atmosphere involved, that's what produces crater-chains. Valles Marineris on Mars may be the result of a large crater-chain.

Antoine Hof · Post by **Antoine Hof** » Thu Nov 17, 2005 2:12 pm

Wow great picture of the asteroid, was looking for it for a project of mine! Thnx!

craterchains · Post by **craterchains** » Thu Nov 17, 2005 3:25 pm

While many accept the "rubble pile" comet theory as to the cause of crater chains, I do not. After over three years of looking at thousands of photographs of crater chains and researching these unique formations of craters there remains no evidence of a rubble pile comet as to the culprit that caused over 90% of these CS types of crater chains. (Concise
Systematic = CS)

Itokawa appears to be a prime example of a rubble pile type comet, at this time. Could Itokawa break up and form a CS type of crater chain? Very doubtful because of the size of the pieces would be too different to create the concise size of the craters in a CS type of crater chain. When a comet breaks up it forms many various size chunks, and they rapidly drift away from each other in all directions along the main track. Thus it is also
doubtful that they would land close enough to make the concise shoulder to shoulder pattern that CS types of crater chains display.

I may not be "politically correct" in refuting the SL9 type of comet breakup creating crater chains, but SL9 gave the best evidence that these types of CS crater chains would NOT form from such a breakup.

Norval

Aqua · Post by **Aqua** » Thu Nov 17, 2005 9:03 pm

Now THAT's a 'ZINGY' image! Cudos' to the Japanese Space Agency for that effort! Indeed.. we are not alone! HO!

Apparently ALL theories of comet formation/accumulation may be 'right'? As we are finding that not all comets are solid.. and not all comets (or asteroids) are 'fluff balls' either!

Further.. not all comets may have been formed with left handed chirality? As some are apparently formed with RIGHT handed chirality... ie. interstellar?

GIVEN that possibility.. then ALL impact energy estimates may need to be re-examined?

That is to say... a comet or asteroid composed of right handed chirality molecules, may, upon impact, react far more energetically than 'normal' or left handed chirality molecules?

Not antimatter.. but dang close?

S. Bilderback · Post by **S. Bilderback** » Thu Nov 17, 2005 10:56 pm

craterchains wrote:While many accept the "rubble pile" comet theory as to the cause of crater chains, I do not.

Most comets and asteroids do not have physical make up to create crater chains, that’s why they are "rare", but some wandering bodies must be made of uniform sized, low cohesion chunks, and with a rotation inline with its decent ... Crater-Chains!

craterchains · Post by **craterchains** » Fri Nov 18, 2005 2:34 am

S. Bilderback

While I would very much enjoy a good discussion about crater chains, this thread is about the asteroid Itokawa. It is about the remarkable Japanese space probe effort to investigate the potentials of space exploration and getting mankind "out there". My hat is off to them. Also about the snide comments made about some of the efforts failures made in the media. Even that APOD used such a poor example of the extremely different surface this asteroid has compared to others. The greatest interest was in a shadow of the satellite? ok.

Should you wish to discuss some aspects of crater chain formation, pick one of the 3 or 4 that APOD has and we can get the ball rolling.

Norval

S. Bilderback · Post by **S. Bilderback** » Fri Nov 18, 2005 3:36 am

I'd love to discuss crater chains, pull one up.
But also, the points I'm making are relevant to the physical makeup of Itokawa - drifting a little but they flow.

RJN · Post by **RJN** » Fri Nov 18, 2005 3:20 pm

I would be curious if anyone noticed that the bottom of Itokawa as captured by the image displayed on the Nov. 16 APOD is roughly circular. Yes, that is surely a chance projection, but it seems to me unlikely that any projection of a low mass body would appear circular. I wonder if the near circularity is an artifact of the field of view of the camera, a statistical fluke, or perhaps something giving a clue to the past of the asteroid. The possibility that the circularity is a relic of some gravitational perturbation from Earth (given that Itokawa is a loose rubble pie), or the relic of its creation impact (given that Itokawa is solid) come to mind. Any thoughts?

- RJN

craterchains · Post by **craterchains** » Sat Nov 19, 2005 1:43 am

RJN
I have to agree that "any" body that shows circular would be of interest. Basic mass gravity ratio's seem to denote that circular will only start at about 900 miles in diameter. If I am correct in my assumption that at that point aprox. mass / gravity becomes great enough to form itself? Basically Itokawa is a "potato" in shape from what I have seen of the couple dozen photos available.

Earth affected this asteroid? I thought it was a Mars crossing orbital asteroid only? But I do see your point. And, as you say, quite possibly it may be a broken chunk of something that was once larger.

Thanks for the input.
Norval

S. Bilderback
Give me a couple days, have alot on the plate for a few days. Then will get into a good
discussion of CS crater chains.

gordhaddow · Post by **gordhaddow** » Mon Nov 21, 2005 11:59 am

Any information on where/how the image is mosaiced? Or am I the only one who sees an apparent linearity within the gouge @ 45deg. below the shadow?
Gord

craterchains · Post by **craterchains** » Mon Nov 21, 2005 6:38 pm

gordhaddow
I think this is a single photo, not made up of several.

My apologies to RJN, Itokawa does cross earth's orbit.

Norval