Oct 26 2014	Peter Utas Discovery and recovery of meteorites from the California Deserts. Location: Slichter 3853 Time: 2:30PM This lecture will discuss which terrains are best suited for hunting meteorites, give examples of recoveries, and briefly illustrate the tracks made by meteorites that have moved across the surface of dry lakes.
Sep 28 2014	Paul Warren Major Messages of Moon Meteorites Location: Slichter 3853 Time: 2:30PM This lecture will briefly cover how we recognize lunar meteorites, what they add to our knowledge of the Moon, and why for many purposes the Apollo lunar samples are still supremely important. This lecture will briefly cover how we recognize lunar meteorites, what they add to our knowledge of the Moon, and why for many purposes the Apollo lunar samples are still supremely important.
Aug 24 2014	Frank Kyte The most meteorite-rich place on Earth... Location: Slichter 3853 Time: 2:30PM Where is it? Unfortunately in one of the most poorly explored places on earth, and on the bottom of the ocean too. But 2.5 million years ago an asteroid deposited more than one kilogram per square meter of meteorite over thousands of square kilometers of the ocean floor near Antarctica.
Jul 20 2014	Kevin McKeegan Meteorites too small to see: collecting micrometeorites and comet dust Location: Slichter 3853 Time: 2:30PM Almost all of the meteorites on display in museums are pebble-sized or larger rocks that come from asteroids. However, most of the extraterrestrial matter coming to the Earth every day is in the form of microscopic cosmic dust, which includes both samples of asteroids and of comets. For decades, NASA has collected this dust high in the Earth's atmosphere using re-purposed U2 spy planes and in 2004 has also collected bonafide comet dust by flying the Stardust spacecraft through the tail of Jupiter-family comet P/Wild2 and returning the sample to the Earth for detailed study. I will discuss these collections, what the cosmic dust looks like, and how its properties compare to those of meteorites.
Jun 29 2014	Alan Rubin Hot Meteorites Location: Slichter 3853 Time: 2:30PM The vast majority of meteorites have experienced relatively high temperatures, ranging from about 600ºC to 1200ºC. As a consequence, these samples have been metamorphosed or melted. Metamorphism involves textural recrystallization, homogenization of mineral chemistry, loss of volatiles, and the formation and growth of new mineral phases. Melting can be partial or total. Among the most important questions in Cosmochemistry is the nature of the mechanism mainly responsible for heating meteorites. One of the top two contenders is heating via the decay of short-lived radioactive isotopes such as 26-Al (aluminum atoms with 13 protons and 13 neutrons) which has a half-life of 730,000 years. The other leading mechanism is collisional heating caused by hypervelocity impacts of projectiles onto asteroidal surfaces. In this lecture, we will discuss the petrologic effects of heating and evaluate the evidence for the leading mechanisms that produced hot meteorites.