Feb

9

2020

Dr. Ashley Davies

Power and Fury: Recent Developments in the Study of Volcanism on Io

Location: Geology Building - Slichter Room 3656
Time: 2:30PM

Volcanoes helped transform the surfaces of the Earth, the other terrestrial planets, and the Moon. However, the biggest volcanic eruptions in the Solar System are taking place not on Earth, but on the Jovian moon Io. This wonder of the Solar System is a fascinating volcanic laboratory where powerful volcanic eruptions result from tidal heating, a process that also affects ice-covered Jovian moon Europa. Yet despite multiple spacecraft visits and spectacular new observations of Io with large Earth-based telescopes, some of the biggest questions about Io's extraordinary volcanoes remain unanswered. Getting the answers requires an understanding of the difficulties of remote sensing of volcanic activity; a new, innovative approach to instrument design; and ultimately a return to Io. Dr. Ashley Davies is a Research Scientist at the Jet Propulsion Laboratory – California Institute of Technology. He received a Doctorate in volcanology from Lancaster University, in the United Kingdom, in 1988. He was a member of the Galileo NIMS Team; is a Co-Investigator on the Europa Clipper Mapping Imaging Spectrometer for Europa (MISE); has written over 100 papers on observing and understanding volcanic processes; and is the author of "Volcanism on Io – A comparison with Earth", published by Cambridge University Press.

Jan

26

2020

Dr. Peter Utas and Dr. Alan Rubin

A coming out party for a large stony meteorite

Location: Geology Building - Slichter Room 3656
Time: 2:30PM

Large iron meteorites are common, big stones are rare. Our atmosphere presents a formidable barrier to large rocks, efficiently transforming boulders into pebbles. But a few survive the fiery plunge. Peter reviews the roster of these great intruders, with a short description of several, and introduces a rare survivor, the 15th largest surviving stone. Discovered five years ago, in Mali or Mauritania, this flight-marked 205-kilogram specimen was largely buried, the soil-line still clearly visible. Rubin describes the analysis and classification of chondritic stones; naked eye examination of hand specimens gives important clues, but quantitative techniques are needed to avoid being misled. Hand samples of chondrites will be available for examination by attendees.