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View Full Version : Double Asteroids Revealed as Twin Piles of Rubble



Fraser
2007-Mar-30, 10:43 PM
Astronomers have turned up many binary asteroids in the Solar System. Instead of a single, solitary spacerock, you've got two objects orbiting a common centre of gravity. ...

Read the full blog entry (http://www.universetoday.com/2007/03/30/double-asteroids-revealed-as-twin-piles-of-rubble/)

sail4evr
2007-Apr-02, 12:18 AM
Would twin piles of rubble show such well defined crater impacts as portrayed by the artist?

01101001
2007-Apr-02, 12:46 AM
Would twin piles of rubble show such well defined crater impacts as portrayed by the artist?

I think that depends upon which imaged rubble pile you might want to model the impression. Mathidle is low density, but I suspect not conclusively a rubble pile. Itokawa is rubble.

Artist's Impression Antiope Doublet (Credit ESO)
http://www.eso.org/outreach/press-rel/pr-2007/images/phot-18a-07-icon.jpg (http://www.eso.org/outreach/press-rel/pr-2007/images/phot-18a-07-normal.jpg)

253 Mathilde (Credit NASA)
http://upload.wikimedia.org/wikipedia/commons/thumb/3/3b/%28253%29_mathilde.jpg/200px-%28253%29_mathilde.jpg (http://en.wikipedia.org/wiki/Image:%28253%29_mathilde.jpg)

25143 Itokawa (Credit JAXA)
http://www.jaxa.jp/projects/sat/muses_c/img/topics_20060602.jpg (http://www.jaxa.jp/projects/sat/muses_c/index_e.html)

antoniseb
2007-Apr-02, 01:17 AM
I think that depends upon which imaged rubble pile you might want to model the impression. Mathidle is low density, but I suspect not conclusively a rubble pile. Itokawa is rubble.

The giant crater on Mathilde is evidence that it is rubble.

tony873004
2007-Apr-10, 07:45 PM
I think that depends upon which imaged rubble pile you might want to model the impression. Mathidle is low density, but I suspect not conclusively a rubble pile. Itokawa is rubble.


Mathidle has a density of only 1.3 g/cc. It would be hard to imagine it as anything other than a pile of rubble.

Itokawa has a density of 1.9 g/cc. I'm just taking a guess here, but its higher density might be because it consists of 2 solid rocks, covered with rubble. If it were pure rubble it probably wouldn't be able to maintain its elongated shape.

SeanU
2007-Apr-23, 01:20 PM
Sorry, what pictures are you looking at?

If it is the two posted by 01101001 look again and say what you see not what's in your head.

Mathilde looks like a very large lump of rock with depressions scattered around it's surface. No rubble to be seen.

Itokawa I've viewed many times and each time it looks like a large glob of material with rubble scattered on its outside, almost as if the rubble is stuck to it, like a balloon with fluff on the outside.

How people come to the conclusion astroids are a piles of rubble i have no idea. No picture of ANY asteroid reveils itself to be a pile of rubble.

Even Deep Impact slammed into Temple 1 and didn't throw up any "rubble", just incredibly fine material.

All we can conclude is that asteroids are large solid objects and appear to be covered with very fine material. Everything else is imagination.

First it was dirty snow balls, now piles of rubble. What next?

tony873004
2007-Apr-26, 10:14 PM
How people come to the conclusion astroids are a piles of rubble i have no idea. No picture of ANY asteroid reveils itself to be a pile of rubble.
They come to this conclusion because their densities are not high enough for them to be solid rock. The pictures don't have enough resolution to show you rubble, just like a picture of people playing volleyball on the beach don't have enough resolution to show you individual grains of sand.

Nick4
2007-Jun-07, 04:17 AM
what are you guys talking about? "rubble pile"?

Noclevername
2007-Jun-07, 04:20 AM
what are you guys talking about? "rubble pile"?

Not a single solid mass, but a loose conglomerate of debris. Many asteroids are thought to be rubble piles.