LPI Seminar Series

Effective January 1, 2011, LPI seminars will be held on Fridays.

LPI seminars are held from 3:30–4:30 p.m. in the Lecture Hall at USRA, 3600 Bay Area Boulevard, Houston, Texas. Refreshments are served at 4:30 p.m. For more information, please contact Yann Sonzogni (phone: 281-486-2199; e-mail:sonzogni@lpi.usra.edu) or Ross Potter (phone: 281-486-2144; e-mail: potter@lpi.usra.edu). A map of the Clear Lake area (PDF format) is available here. The Acrobat Reader 8.0 is available from Adobe. This schedule is subject to revision.

See also the Rice University Department of Physics and Astronomy Colloquia and the Department of Earth Science Colloquia pages for other space science talks in the Houston area.

May 2013

Friday, May 31, 2013 - Lecture Hall, 3:30 PM

Tom Zega, University of Arizona
Decoding the High-Temperature Origins of Refractory Oxides from Ancient Stars

As stars evolve, they shed their matter through dust-driven stellar winds or explosive events such as supernovae. These stellar ashes can enter the interstellar medium and become the starting material for a new star. Our own solar system formed partly from the remnants of ancient stars, and it was long ago suspected that individual grains of this presolar stardust material should have survived intact within the solid relics leftover from its birth, i.e., primitive meteorites. The isolation and measurement of presolar grains has been a decades-long struggle, largely because many of them occur intimately mixed at the nanometer scale in chondritic meteorites - the bulk of which contain phases that formed in our own solar system. In recent years, developments in electron and ion optics have revolutionized our ability to measure the isotopic composition of a grain, extract it in situ, and investigate its crystal chemistry and structure. Such information is fundamental to inferring the origins of such grains, e.g., the type, mass, and composition of their parent stars as well as the thermodynamic processes of their circumstellar envelopes and secondary processing they experienced within our solar system. I will show how secondary ion mass spectrometry, focused-ion-beam scanning-electron-microscopy, and transmission electron microscopy (TEM) can be combined to gain insight into the origin of presolar spinel (MgAl2O4) and hibonite (CaAl12O19) grains.

June 2013

Friday, June 7, 2013 - Lecture Hall, 3:30 PM

Shoshana Weider
The Surface Composition of Mercury From MESSENGER Data

Geochemical results from the X-Ray and Gamma-Ray Spectrometers onboard the MESSENGER spacecraft, and insights they provide into Mercury's formation and geological evolution Shoshana Weider

Friday, June 14, 2013 - Lecture Hall, 3:30 PM

Kelsi Singer, Washington University, St. Louis
Massive Ice Avalanches on Iapetus Mobilized by Friction Reduction During Flash Heating

Large ice avalanches on saturnian satellites exhibit a behavior similar to long-runout landslides found across the solar system: some mechanism (or mechanisms) apparently reduces the material’s friction, allowing the landslides to travel 10-30 times their drop heights (as opposed to ~2x for a more “normal” frictional regime). These landslides achieve immense runout lengths, even over variable slopes and topography. Landslides on Iapetus are some of the longest and most voluminous in the solar system, reaching lengths of 80 km. I will compare the long-runout landslides on icy satellites to their rocky cousins found on Earth and Mars, and discuss a possible friction reduction mechanism through flash heating.

Friday, June 21, 2013 - Lecture Hall, 3:30 PM

Francis McCubbin, University of New Mexico
TBD

Friday, June 28, 2013 - Lecture Hall, 3:30 PM

Francis McCubbin, University of New Mexico
TBD TBD

July 2013

Friday, July 26, 2013 - Lecture Hall, 3:30 PM

Oliver White, Lunar and Planetary Institute
TBD