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Astronomy Picture of the Day -- The Missing Craters of Asteroid Itokawa
NASA ^
| February 09, 2014
| (see photo credit)
Posted on 02/09/2014 12:19:45 PM PST by SunkenCiv
Explanation: Where are the craters on asteroid Itokawa? Missing -- unexpectedly. The Japanese robot probe Hayabusa approached the Earth-crossing asteroid in 2005 and returned pictures showing a surface unlike any other Solar System body yet photographed -- a surface possibly devoid of craters. The leading hypothesis for the lack of common circular indentations is that asteroid Itokawa is a rubble pile -- a bunch of rocks and ice chunks only loosely held together by a small amount of gravity. If so, craters might not form so easily -- or be filled in whenever the asteroid gets jiggled by a passing planet or struck by a massive meteor. Recent Earth-based observations of asteroid Itokawa have shown that one part of the interior even has a higher average interior density than the other part, another unexpected discovery. The Hayabusa mission returned soil samples from Itokawa which are also giving clues the ancient history of the unusual asteroid and our entire Solar System.
(Excerpt) Read more at 129.164.179.22 ...
TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; asteroid; asteroiditokawa; astronomy; hayabusa; itokawa; japan; science
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[Credit & Copyright: ISAS, JAXA]
1
posted on
02/09/2014 12:19:45 PM PST
by
SunkenCiv
To: brytlea; cripplecreek; decimon; bigheadfred; KoRn; Grammy; married21; steelyourfaith; Mmogamer; ...
2
posted on
02/09/2014 12:21:20 PM PST
by
SunkenCiv
(http://www.freerepublic.com/~mestamachine/)
To: SunkenCiv
That’s strange. Thanks for the post.
3
posted on
02/09/2014 12:25:27 PM PST
by
FlingWingFlyer
(ObamaCare. The "global warming" of healthcare plans.)
To: SunkenCiv
4
posted on
02/09/2014 12:26:50 PM PST
by
bmwcyle
(People who do not study history are destine to believe really ignorant statements.)
To: SunkenCiv
Probably recently broken apart and then reformed. When a potato starts looking that bad, do you throw it out or make soup?
5
posted on
02/09/2014 12:32:46 PM PST
by
Telepathic Intruder
(The only thing the Left has learned from the failures of socialism is not to call it that)
To: SunkenCiv
Does it melt and re-freeze?
6
posted on
02/09/2014 12:36:24 PM PST
by
Triple
(Socialism denies people the right to the fruits of their labor, and is as abhorrent as slavery)
To: SunkenCiv
7
posted on
02/09/2014 12:40:23 PM PST
by
Chode
(Stand UP and Be Counted, or line up and be numbered - *DTOM* -vvv- NO Pity for the LAZY - 86-44)
To: FlingWingFlyer; bmwcyle; Telepathic Intruder; Triple; Chode
This article reiterates the 'rubble pile' explanation, but notes that one end is lower density than the other. That could be suggestive of water ice. My view is that all the Earth-crossers formerly were part of now-extinct comets.
KEYWORDS: asteroid;
asteroiditokawa;
hayabusa;
itokawa
8
posted on
02/09/2014 1:01:30 PM PST
by
SunkenCiv
(http://www.freerepublic.com/~mestamachine/)
To: SunkenCiv
that's a valid explanation
9
posted on
02/09/2014 1:10:59 PM PST
by
Chode
(Stand UP and Be Counted, or line up and be numbered - *DTOM* -vvv- NO Pity for the LAZY - 86-44)
To: SunkenCiv
That’s interesting, actually. Then they’re constantly being replenished even with the occasional Tunguska event. There’s just a tiny whisper of gravity holding asteroids together, however. Low density does not necessarily imply light elements.
10
posted on
02/09/2014 1:29:47 PM PST
by
Telepathic Intruder
(The only thing the Left has learned from the failures of socialism is not to call it that)
11
posted on
02/09/2014 1:31:31 PM PST
by
shibumi
(Cover it with gas and set it on fire.)
12
posted on
02/09/2014 1:56:42 PM PST
by
RedMDer
(Happy with this, America? Make your voices heard. 2014 is just around the corner. ~ Sarah Palin)
To: Chode
13
posted on
02/09/2014 2:17:14 PM PST
by
SunkenCiv
(http://www.freerepublic.com/~mestamachine/)
To: Telepathic Intruder
Quite right, there could be voids in the less dense part, much as there may be in one of Mars’ moons.
14
posted on
02/09/2014 2:17:52 PM PST
by
SunkenCiv
(http://www.freerepublic.com/~mestamachine/)
To: SunkenCiv
gravity surly works on all things
15
posted on
02/09/2014 2:19:43 PM PST
by
Chode
(Stand UP and Be Counted, or line up and be numbered - *DTOM* -vvv- NO Pity for the LAZY - 86-44)
To: SunkenCiv
It will go good with the Sour Cream Belt of the Milky Way.
16
posted on
02/09/2014 2:22:01 PM PST
by
TigersEye
(Stupid is a Progressive disease.)
To: SunkenCiv
"The Hayabusa mission returned soil samples from Itokawa"huh? thats a pretty big deal- why wasn't I notified?
17
posted on
02/09/2014 2:39:01 PM PST
by
Mr. K
(If you like your constitution, you can keep it...Period.)
To: SunkenCiv
Haven’t heard that. Deimos I assume?
18
posted on
02/09/2014 2:41:09 PM PST
by
Telepathic Intruder
(The only thing the Left has learned from the failures of socialism is not to call it that)
To: SunkenCiv
This article reiterates the 'rubble pile' explanation, but notes that one end is lower density than the other. That could be suggestive of water ice. My view is that all the Earth-crossers formerly were part of now-extinct comets. Unfortunately for your theory, every comet we've analyzed or visited has shown essentially zero water. . . and is indistinguishable from any other asteroid except for orbit and electrical charge.
19
posted on
02/09/2014 2:50:23 PM PST
by
Swordmaker
(This tag line is a Microsoft insult free zone... but if the insults to Mac users continue...)
To: Telepathic Intruder
20
posted on
02/09/2014 2:52:21 PM PST
by
SunkenCiv
(http://www.freerepublic.com/~mestamachine/)
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