When
3:30 p.m., Oct. 18, 2011
Where
Kuiper Space Sciences 308
Dr. Frank Gyngard
Washington University, St. Louis
"You're Older Than You Think: Constraining Timescales Before Solar System Formation with Grains of Stardust"
Abstract:
Presolar grains are literally astrophysical fossils leftover from long dead stars and were incorporated into some primitive meteorites. These fossils, termed stardust, predate the formation of the Solar System and escaped its isotopic homogenization, retaining their original compositions. Determining absolute ages of these grains by applying typical chronometer schemes, such as Pb-Pb dating, are challenging both experimentally and theoretically. Recent advances in estimating the Galactic Cosmic Ray exposure ages of some unique stardust grains, using isotopic measurements from both NanoSIMS and noble gas mass spectrometers, allow us to place constraints on the amount of time dust spent in the interstellar medium before incorporation into the early Solar System. And by the way...you are stardust.
Washington University, St. Louis
"You're Older Than You Think: Constraining Timescales Before Solar System Formation with Grains of Stardust"
Abstract:
Presolar grains are literally astrophysical fossils leftover from long dead stars and were incorporated into some primitive meteorites. These fossils, termed stardust, predate the formation of the Solar System and escaped its isotopic homogenization, retaining their original compositions. Determining absolute ages of these grains by applying typical chronometer schemes, such as Pb-Pb dating, are challenging both experimentally and theoretically. Recent advances in estimating the Galactic Cosmic Ray exposure ages of some unique stardust grains, using isotopic measurements from both NanoSIMS and noble gas mass spectrometers, allow us to place constraints on the amount of time dust spent in the interstellar medium before incorporation into the early Solar System. And by the way...you are stardust.