Starship Asterisk*

The Regolith of Asteroid Eros

Explanation: From fifty kilometers above asteroid Eros, the surface inside one of its largest craters appears covered with an unusual substance: regolith. The thickness and composition of the surface dust that is regolith remains a topic of much research. Much of the regolith on 433 Eros was probably created by numerous small impacts during its long history. In this representative-color view taken by the robot spacecraft NEAR-SHOEMAKER that orbited Eros in 2000 and 2001, brown areas indicate regolith that has been chemically altered by exposure to the solar wind during micrometeorite impacts. White areas are thought to have undergone relatively less exposure. The boulders visible inside the crater appear brown, indicating either that they are old enough to have a surface itself tanned by the solar wind, or that they have somehow become covered with some dark surface dust. This July, NASA's Dawn spacecraft will orbit giant main belt asteroid Vesta.

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brown areas indicate regolith that has been chemically altered by exposure to the solar wind during micrometeorite impacts.

I don't understand the "during micrometeorite impacts" part. Why wouldn't it be altered by the solar wind at other times? Is it that only subsurface material is chemically altered, but if so why couldn't it be that the brown color comes from subsurface material that hasn't yet been exposed to as much solar wind instead?

To all extraterrestrial beings,

would you please retrieve and return to the earth the spaceprobes indicated. thank you for your cooperation.

-messenger

-mariner 10

-

Astronauts invent fender extender! This was to protect from moon dust.

Exactly how many extraterrestrial bodies have our probes visited?

IMHO speculation on the nature of, "The Regolith of Asteroid Eros", is premature - at best. Better to imagine, "How many angels can dance on the head of a pin?".

jman wrote:Exactly how many extraterrestrial bodies have our probes visited?

Here is a list of All probes to visit the various solar system bodies
WIKI list of Solar System Probes

this is the image that caught my attention. That bright square object on the right, inside the carter lkooks fresh and tto square

http://near.jhuapl.edu/iod/20000503/index.html

Wolf Kotenberg wrote:this is the image that caught my attention. That bright square object on the right, inside the carter lkooks fresh and tto square
http://near.jhuapl.edu/iod/20000503/index.html

Uh oh. I told them the camouflage wasn't working.

Rob

BMAONE23 wrote:Here is a list of All probes to visit the various solar system bodies
WIKI list of Solar System Probes

Thanks!

jman wrote:

BMAONE23 wrote:Here is a list of All probes to visit the various solar system bodies
WIKI list of Solar System Probes

Thanks!

You're welcome