Mike Savina, Ph.D. from the Lawrence Livermore National Laboratory, joined us to discuss recent revelations made possible by studying stardust.
Stars manufactured all the elements heavier than helium, and thus provided the building blocks of planets such as Earth. Stardust is ubiquitous in the Milky Way, and each grain contains elements that were synthesized by nuclear reactions during some star’s lifetime. Although most grains were destroyed when the Solar System formed, a few survived and eventually fell to Earth in the interiors of primitive meteorites. These microscopic grains are actual samples of stars, and give us an extraordinary opportunity to study stellar nucleosynthesis – the astrophysical process that creates atomic nuclei – in the laboratory. Cashing in on this opportunity is extremely challenging: we have to measure the isotopic compositions of trace elements in micron-sized grains, which means that there are very few atoms of the element of interest in any given sample. I will review the history of “hands-on astrophysics” and show recent results using a unique home-made instrument that reveals the bizarre isotopic compositions of elements such as molybdenum, zirconium, and barium produced in stars. This not only gives us insight into the lives and deaths of stars, it is also applied to man-made nuclear materials for forensic and non-proliferation applications.
Mike Savina received his Ph.D. in physical chemistry from The University of Michigan. He is currently a Physical Chemist at Lawrence Livermore National Laboratory specializing in laser-based methods of mass spectrometry. Mike’s interests include cosmochemistry, nuclear forensics, and ultra-trace elemental analysis. You can listen to his fascinating presentation below.