What is the universe made of? What is the biological basis of consciousness? Can the world continue to sustain a growing population and growing consumption? In celebration of its 125th anniversary, Science has taken stock of some of the most important, yet-unanswered scientific questions and delved into 25 of them for a closer look at just what we do and don't yet know about our universe.

Questions like these show us how far science has come in explaining the natural world, and they also fuel the discoveries of the future, writes author and journalist Tom Siegfried in an introduction to the special 1 July issue of Science, published by AAAS, the nonprofit science society.

In the special issue, Science's editors have identified 125 "big questions" that scientists have yet to answer. Rather than a comprehensive inventory, this list is a significant sampling of the major questions facing science today. Science's news team has also focused on 25 of these questions in a special package of essays.

"Today, science's most profound questions address some of the largest phenomena in the cosmos and some of the smallest. We may never fully answer some of these questions, but we'll advance our knowledge and society in the process of trying," said Donald Kennedy, Science's editor-in-chief.

"As Science celebrates its 125th birthday, we've recognized that an examination of science's outstanding mysteries also reflects its tremendous accomplishments," he added.

Founded by Thomas A. Edison, Science debuted on July 3 1880, with 12 pages of articles on the possibility of elect
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Contact: Jessica Lawrence-Hurt
jlawrenc@aaas.org
1-202-326-7088
American Association for the Advancement of Science
30-Jun-2005