UV Space Weathering in Asteroids Surface: LIBS analysis and the key to understand subsur- face composition.

SUCH, PAMELA; SOBRON, PABLO

Montevideo

Congreso; Asteroids, Comets, Meteors ACM 2017; 2017

During years scientis studied the vi- sible and near-infrared spectra of re- flected sunlight from asteroid surfa- ces exhibit features for identifying surface mineralogy. However, the very surfaces that are observed by remote-sensing are also subject to solar wind particles and change in the surface structure product of coli- sions. We know that space weathe- ring is the main cause of modifica- tion of an asteroid´s surface and that its time-dependent, that is evidence in the reflectance spectrum obtain by remote sensing. Such space weat- hering has confused the interpreta- tions of telescopic spectra of aste- roids, especially concerning to the understanding of the mineralogy composition. Recent spacecraft stu- dies of asteroids (Eros by NEAR- Shoemaker, Vesta by Dawn, Itokawa by Hayabusa) have documented as- pects of space weathering proces- ses, but we still do not understand the physics of space weathering well enough to confidently assay minera- logy of diverse asteroids by remote- sensing. LIBS techonology can alouds us to obtain direct data from surface analysis in a future misión. The original composition of the aste- roid surface will condition the result of the space-weathering product in time. During this study LIBS was being test to analyze and study alte- red and expose rock samples from a outcrops of intermidiate to basic vol- canis rocks altered in surface by anargilic ? propilitic thermal alteration with the result of mineralogy altera- tion and depositation of sulfides, me- tals and develop of clays.This study and more we will use in time to correlate results from LIBS analisys from altered exposed rocks like the result of the alteration of ori- ginal outcrops. And will be a key in order to start studying and un- derstanding how UV space weathe- ring can altered and change the mi- neralogy of an asteroid surface and to correlate this one with the original sub-surface composition.