About 350 meteorite experts are expected at the 70th Annual Meeting of the Meteoritical Society, to be held Aug. 13-17 in Tucson. Coincidentally, one of the best views of the Perseid meteor shower seen from Tucson in years is expected that week, said the University of Arizona (UA) scientists who are hosting the event. The Meteoritical Society is the world's largest organization devoted to the study of meteorites and other extraterrestrial material. The nonprofit scholarly organization was founded in 1933 and now includes members from 33 countries. They specialize in planetary science topics such as meteorites, cosmic dust, asteroids and comets, natural satellites, planets, impacts and the origins of the solar system. The society publishes the Meteoritical Bulletin, which records all known meteorites, and the planetary science journal Meteoritics and Planetary Science which is edited at UA offices in Tucson. The 70th annual meeting opens during the night when the Perseids meteor shower is at its peak, during a new moon. Meeting organizers will kick off the conference with an Aug. 12 meteor shower viewing party (for conferees only) under the dark skies at the meeting site, the JW Marriott Starrpass Resort & Spa, 3800 W. Starr Pass Blvd. Scientists will give more than 300 talks and poster presentations on topics including early solar system formation and planetary impact cratering, astrobiology, and the recent Genesis and Stardust space missions, said Timothy Jull, chairman of the organizing committee and a UA geosciences professor. On Aug. 15, Peter Smith of UA's Lunar and Planetary Laboratory, principal investigator for the Phoenix Scout Mars mission, will give the society's Barringer Lecture. The Phoenix mission will launch Aug. 3; the spacecraft will land in Mars' northern arctic region in May 2008 and use a robotic arm and deck of sophisticated science instruments to explore questions on Mars' potential to support life, the history of water, and changes in Martian climate. Sessions on Arizona's Meteor Crater (Barringer Crater) and other impact craters; on protoplanetary dust; and on advances in dating the exposure ages and irradiation history of meteorites by the 'cosmogenic radionuclides' they contain, will be held on Aug. 13. Cosmogenic radionuclides are radioactive elements produced by cosmic rays in space. The university's NSF-Arizona Accelerator Mass Spectrometer Facility, which Jull directs, focuses much research in this area. A session on on chondrules and chondrule formation will be presented Aug. 14. Chondrules are small grains of minerals found in some meteorites. Scientists believe the minerals formed as hot gases condensed during solar system formation. The UA geosciences department and UA Lunar and Planetary Laboratory are hosting the conference. UA conference sponsors also include the College of Science; the UA departments of planetary sciences geosciences and physics; the NSF-Arizona AMS Laboratory, the Southwest Meteorite Center, Steward Observatory; the Life and Planets Astrobiology Center (LaPLACE) and the University of Arizona Press. Meeting sponsors also include the Tucson-based Planetary Science Institute, the Houston-based Lunar and Planetary Institute, Lockheed Martin, NASA, Barringer Crater Company, the Tucson Visitors and Convention Bureau and others. During the last decade, the Meteoritical Society has held its annual meeting in cities including Zurich, Rio de Janeiro, Rome (Vatican Observatory), Chicago, Johannesburg and Dublin. The next two meetings will be held in Japan and France. For more information, visit: metsoc2007.org/