Cosmochemistry; presolar grains and organic matter in meteorites; isotopic chemistry
M.S., Geochemistry, Durham University, 2006 Ph. D., Cosmochemistry and Planetary Science, The Open University, 2009
Jemma Davidson is a cosmochemist who studies organic matter and presolar grains in primitive meteorites. In particular, her research focuses on the carbonaceous chondrites and what their organic and presolar material can tell us about meteorite formation in the early Solar System and how this material was later altered on their asteroid parent bodies. Davidson is working with Staff Scientists, Larry Nittler and Conel Alexander.
Presolar grains, sometimes also called interstellar grains, are tiny microscopic pieces of stardust formed by stars that lived and died long before our Solar System even formed. They are literally tiny pieces of stars that can be studied in the laboratory. Some presolar grains survived the formation of the Solar System by hiding inside asteroids and can be found in meteorites that have remained mostly unaltered since their formation. By using high-resolution imaging and spectrometry techniques we can not only find them and study their appearance but we can also determine their isotopic compositions, which in turn can tell us about how stars create elements and evolve over time (also known as stellar nucleosynthesis). Presolar grains exist as different types including silicates, oxides, carbides, graphite and even diamonds. Different types of presolar grain are destroyed at different temperatures during heating and/or interaction with water. As a result, presolar grains can act as tracers of parent body alteration and allow us to investigate how heat and water have interacted on different parent asteroids to alter primitive solar system materials. This is important for understanding how early Solar System materials evolved to form other types of asteroids and planets.
As an undergraduate, Davidson studied Geological Sciences at the Durham University in the north of England where her MSci thesis concerned the petrology and geochemistry of lunar basalts from the Apollo 15 and 17 missions. She received her PhD in Cosmochemistry from the UK’s Open University in 2009 where she studied presolar grains in primitive meteorites and interplanetary dust particles. She then completed a two year Postdoctoral position at the University of Arizona where she worked on the OSIRIS-REx asteroid sample return mission and studied the links between CV and CK carbonaceous chondrites, followed by a year at the University of Hawai’i at Manoa where she studied the secondary alteration mineralogy of the CK chondrites. Davidson’s analytical specialties include SIMS (secondary ionization mass spectrometry), EMPA (electron microprobe analysis), and Raman spectroscopy. She also has experience with LIBS (laser-induced breakdown spectroscopy), LA-ICP-MS (laser ablation inductively coupled mass spectrometry), FIB-SEM (focused ion beam scanning electron microscopy) and TEM (transmission electron microscopy) analysis.