Robert Miller Hazen (born November 1, 1948) is an American mineralogist and astrobiologist. He is a research scientist at the Carnegie Institution of Washington's Geophysical Laboratory and Clarence Robinson Professor of Earth Science at George Mason University, in the United States. Hazen is the Executive Director of the Deep Carbon Observatory.
Hazen received a B.S. and M.S. in Earth Science at the Massachusetts Institute of Technology 1971, and a Ph.D. at Harvard University in Mineralogy & Crystallography 1975. After studies as NATO Postdoctoral Fellow at Cambridge University in England, he joined the Carnegie Institution's research effort.
Hazen is author of more than 350 articles and 20 books on science, history, and music. A Fellow of the American Association for the Advancement of Science, he has received the Mineralogical Society of America Award (1982), the American Chemical Society Ipatieff Prize (1986), the ASCAP Deems Taylor Award (1989), the Educational Press Association Award (1992), the E.A. Wood Science Writing Award (1998), and the Distinguished Public Service Medal of the Mineralogical Society of America (2009). He has presented numerous named lectures at universities, and is currently Sigma Xi Distinguished Lecturer (2008–2010). He served as Distinguished Lecturer for the Mineralogical Society of America, and is a Past President of the Society. Hazen's recent research focuses on the role of minerals in the origin of life, including such processes as mineral-catalyzed organic synthesis and the selective adsorption of organic molecules on mineral surfaces. He has also developed a new approach to mineralogy, called "mineral evolution," which explores the co-evolution of the geo- and biospheres. He is also an adviser to the Microbes Mind Forum. The mineral hazenite was named in his honor. Hazen and his colleagues started the Carbon Mineral Challenge, a citizen science project dedicated to accelerating the discovery of "missing" carbon-bearing minerals.