M. Darby Dyar

  • Kennedy-Schelkunoff Professor of Astronomy
  • Chair of Astronomy
  • on leave fall 2022
Darby Dyar, chair of the Astronomy Department

The primary goal of Darby Dyar's research is to understand how hydrogen and oxygen are distributed throughout our solar system, particularly in terrestrial bodies such as the Earth, the Moon, Mars, and the parent bodies of meteorites. Dyar uses Mössbauer, reflectance, Raman, synchrotron, and LIBS spectroscopies. She studies rocks from diverse localities on Earth from the deep oceans to Antarctica, as well as lunar rocks and meteorite samples.

Dyar has written more than 260 papers in scientific journals and has been awarded more than $10 million in diverse grants from NASA and NSF. These include support for her participation on the Mars Science Laboratory science team; its calibration target was built at the College. She also serves on three of the eight NASA Solar System Exploration Virtual Institutes. She is pioneering development of novel machine learning techniques for interpretation of spectroscopic data. In 2016, Dyar received the G.K. Gilbert Award from the Planetary Geology Division of the Geological Society of America for outstanding contributions to the solution of fundamental problems in planetary geology. In 2017, she was honored with the Hawley Medal from the Mineralogical Society of Canada. In 2018, she received the Eugene Shoemaker Distinguished Scientist Medal from NASA’s Solar System Exploration Research Virtual Institute for significant contributions to the field of lunar science. She is a Fellow of the Mineralogical Society of America, the Geological Society of American, and the Geochemical Society.

Dyar’s research program supports 6-8 Mount Holyoke undergraduate researchers in her Mineral Spectroscopy Laboratory each year, as well as other students from the Five College Astronomy Department. Those students work closely with research staff and post-docs at the College as well as several graduate students at the University of Massachusetts. Dyar and her students represent the College at various national and international conferences each year as well as various alumnae groups.

Areas of Expertise

Minerals; minerals and health; Mössbauer spectroscopy; Mars; Moon; planetary science; optical spectroscopy; synchrotron spectroscopy; FTIR spectroscopy; metamorphic geology; water in minerals


  • Ph.D., Massachusetts Institute of Technology
  • B.A., Wellesley College

Happening at Mount Holyoke

News about M. Darby Dyar

New evidence from old pictures has reignited the search for volcanism on Venus, but the VERITAS mission is expected to reveal the truth, says Mount Holyoke’s Darby Dyar.

Mount Holyoke College’s Darby Dyar explains the enduring mystery of Earth’s unusual moon.

Mount Holyoke astronomer Darby Dyar is among the planetary scientists who will lead NASA’s new mission to explore the surface of Earth’s fiery twin.

Recent Grants

Received a grant from the National Aeronautics and Space Administration (NASA) for Collaborative Research: Redox Ratios in Amphiboles as Proxies for Volatile Budgets in Igneous Systems. The project is for three years.

Recent Publications

Ytsma, C., and Dyar, M.D. (2022) Calculations of limits of blank, limits of detection, and limits of quantification for multivariate analyses of laser-induced breakdown spectroscopy (LIBS) in geological materials. Spectrochimica Acta Part B, 191, 106395.

Steven, C.J., Dyar, MD., McCanta, M.C., Newville, M., and Lanzirotti, A. (2022) The absorption indicatrix as an empirical model to describe anisotropy in x-ray absorption spectra of pyroxenes. American Mineralogist, 107, 654-663. Doi: 10.2138/am-2021-7950.

Leight, C.J., McCanta, M.C., Glotch, T.D., Thomson, B.J., Ye, Cheng, and Dyar, M.D. (2022) Characterization of tephra deposits using VNIR and MIR spectroscopy: A comprehensive terrestrial tephra spectral library. Remote Sensing of the Environment, 273, 112965.

Dyar, M.D., and Ytsma, C.R. (2021) Effect of data set size on geochemical accuracy with laser-induced breakdown spectroscopy. Spectrochimica Acta B, 177, 106073.

Helbert, J., Maturilli, A., Dyar, M.D., and Alemanno, G. (2021) Deriving iron contents from past and future Venus surface spectra with new high temperature laboratory emissivity data. Science Advances, 7, eaba9428.

Recent Awards

Named as a recipient of Wellesley College’s 2020 Alumnae Achievement Award.

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