Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 17 September 2004:
Vol. 305. no. 5691, pp. 1729 - 1730
DOI: 10.1126/science.1102893
Prev | Table of Contents | Next

Perspectives

PLANETARY SCIENCE:
Predicting the Sun's Oxygen Isotope Composition

Qing-zhu Yin

Oxygen-isotope ratios in different solar system materials indicate that 16O-rich and 16O-poor reservoirs must have existed in the early solar system. When, and where, such signatures evolved and how the solar system acquired such signatures has remained elusive. In his Perspective, Yin highlights a new class of models, including that of Yurimoto and Kuramoto, which provide a potential solution of this longstanding problem. The new model (4) focuses on selective ultraviolet photodissociation of CO in the parent molecular cloud that collapsed to form the solar system. Subsequent interactions among H2O, CO, and dust grains then result in the observed isotopic signatures in planetary materials. The predicted oxygen isotope composition of the Sun, cometary H2O, and cometary CO can soon be tested by NASA's Genesis and Stardust missions.

The author is in the Department of Geology, University of California, Davis, CA 95616, USA. E-mail: qyin{at}ucdavis.edu

Read the Full Text

To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)