February 7, 2020
3:00pm in PLS 1140
Doug Hemingway from Carnegie
Magnetic anomalies and the color of the Moon—insights from lunar swirls

Abstract: An enduring mystery since Apollo is that, in spite of the Moon's lack of a global magnetic field, the surface is nevertheless dotted with regional magnetic fields strong enough to be detected from orbit. Did the Moon once have an intrinsic global field that magnetized parts of the crust but has since decayed away? Adding to the puzzle, many of these magnetic anomalies are accompanied by enigmatic optical anomalies known as lunar swirls, which may arise as a result of local variations in space weathering—the poorly understood processes by which the optical properties of airless bodies change over time. Here I will show that we can use swirls to tell us about: 1) the structure of near surface magnetic fields and the characteristics of the underlying magnetic sources; and 2) the optical effects of solar wind weathering and the resulting systematic latitudinal variation in the color of the Moon. These results have implications for the origins of the Moon's crustal magnetic anomalies, the nature of space weathering processes, and the way spectral observations are interpreted across the lunar surface.

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February 14, 2020
3:00pm in PLS 1140
Ellen Syracuse from LANL/DOE
February 21, 2020
3:00pm in PLS 1140
Joyce Sim from Carnegie DTM
February 28, 2020
3:00pm in PLS 1140
Jacob Richardson from NASA Goddard Sace Flight Center
Exploring volcanoes in Central Iceland as Analogs for Planetary Environments

Abstract: Volcanoes are found on all planetary bodies larger than Ceres. Understanding how they erupted enables us to understand the geologic past of a planet and its current distribution of materials at or near the surface. My team has investigated two neighboring volcanoes, Holuhraun and Askja, in central Iceland to survey eruption deposits that are similar to deposits we observe on Mars and the Moon. The 2014-5 Holuhraun eruption produced the most recent flood lava on Earth and its largest source vent is actively degrading. We have monitored this degradation since 2015 to characterize how different volcanic materials and landscapes change over time. Askja deposited blankets of tephra over snowfall in 1875 and 1961. We have surveyed the remaining ice deposits with ground penetrating radar to improve our ability to identify buried ice during future missions to planetary surfaces.

March 27, 2020
3:00pm in PLS 1140
Andrew Knoll from Harvard University
Helz lecture (03/26): The Deep History of Life
Department colloquium (03/27): Systems Paleontology
April 3, 2020
3:00pm in PLS 1140
Adam Simon from University of Michigan
April 10, 2020
3:00pm in PLS 1140
Don Fisher from Penn State
Geochemical, Mechanical, and Fluid flow Models for the Subduction Interface based on Field Observations
April 17, 2020
3:00pm in PLS 1140
Jeff Freymueller from Michigan State University
May 1, 2020
3:00pm in PLS 1140
Hannah Kerner from University of Maryland

The coordinator for the Colloquium Series is Dr. Mong-Han Huang. You can contact him at mhhuang@umd.edu.
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