A1 Refereed original research article in a scientific journal

Dust from collisions: A way to probe the composition of exo-planets?




AuthorsMorlok Andreas, Mason Andrew B, Anand Mahesh, Lisse Carey M, Bullock Emma S, Grady Monica M

PublisherElsevier

Publication year2014

JournalIcarus

Volume239

First page 1

Last page14

Number of pages14

ISSN0019-1035

DOIhttps://doi.org/10.1016/j.icarus.2014.05.024

Web address http://www.sciencedirect.com/science/article/pii/S0019103514002772


Abstract

In order to link infrared observations of dust formed during planet formation in debris disks to mid-infrared spectroscopic data of planetary materials from differentiated terrestrial and asteroidal bodies, we obtained absorption spectra of a representative suite of terrestrial crustal and mantle materials, and of typical martian meteorites.

A series of debris disk spectra characterized by a strong feature in the 9.0-9.5 mum range (HD23514, HD15407a, HD172555 and HD165014), is comparable to materials that underwent shock, collision or high temperature events. These are amorphous materials such as tektites, SiO2-glass, obsidian, and highly shocked shergottites as well as inclusions from mesosiderites (group A).

A second group (BD+20307, Beta Pictoris, HD145263, ID8, HD113766, HD69830, P1121, and Eta Corvi) have strong pyroxene and olivine bands in the 9-12 mum range and is very similar to ultramafic rocks (e.g. harzburgite, dunite) (group B).

This could indicate the occurrence of differentiated materials similar to those in our Solar System in these other systems.

However, mixing of projectile and target material, as well as that of crustal and mantle material has to be taken into account in large scale events like hit-and-run and giant collisions or even large-scale planetary impacts. This could explain the olivine-dominated dust of group B.

The crustal-type material of group A would possibly require the stripping of upper layers by grazing-style hit-and run encounters or high energy events like evaporation/condensation in giant collisions. In tidal disruptions or the involvement of predominantly icy/water bodies the resulting mineral dust would originate mainly in one of the involved planetesimals. This could allow attributing the observed composition to a specific body (such as e.g. Eta Corvi).




Last updated on 2024-26-11 at 22:32