Picoastronomy: an electron microscopist's view of the history of the Solar System

Event Dates: 

Wednesday, September 12, 2018 - 10:00am

CTQM Seminar Type: 

  • Related Seminar Series

Speaker Name(s): 

Rhonda Stroud

Speaker Affiliation(s): 

U.S. Naval Research Laboratory

Abstract, Event Details: 

Host: Mihaly Horanyi. Colloquia are Wednesdays at 4:00 p.m. in DUAN G1B20, unless otherwise noted. Abstract: A wide range of astrophysical processes, from condensation of dust particles in circumstellar envelopes to space weathering on airless bodies, are inherently pico-to-nanoscale phenomena. Thus, an electron microscope, used for direct observation of planetary materials in the laboratory, can be as much of an astronomical tool as a telescope pointed at the sky. The energy resolution of state-of-the-art monochromated scanning transmission electron microscopes (STEMs), as low as 10 meV, makes it possible to directly observe the infra-red optical properties of individual cosmic dust grains in the 2 to 25 um range. Thus, distinguishing the 10-um and 18-um features of individual bonafide astrosilicates is now possible. Furthermore, the spatial resolution and sensitivity of the STEM enables imaging and at spectroscopy at scales down to the single atom. Samples of nanomaterials from diverse classes of stars from red giants to supernovae, from asteroids and comets, and the surface of the Moon are all available for laboratory studies. Results of these studies can help aid in the understanding of the formation and evolution of solar systems, and even provide clues for advancing the development of technologically important materials, such as doped nanodiamonds, SiC and graphene.