Mark Pecaut

Associate Professor of Physics at Rockhurst University

Mark Pecaut

Research Interests

  • The star formation histories of young, nearby OB associations and their effect on the solar neighborhood; smaller, nearby moving groups.
  • Spectral classification, ages of stars, kinematics, formation of solar systems
  • Fundamental properties of stars, stellar evolution.


I've done a few different things. I went to school in Kirksville, MO and received my BS in Physics and Mathematics from Truman State University in 1998. After graduation, I briefly went to MIT but then quit and worked as a civil draftsman, network administrator and a web lackey until 2001 when I joined the Peace Corps with my wife. I taught Physics and Mathematics in Ghana, West Africa until 2003. After the Peace Corps we moved to Cheyenne, Wyoming, where I wore many hats as PHP and .NET programmer, a firewall administrator, and database administrator. Most of my time was spent building information systems for the Wyoming department of Workforce Services. I quit and went to graduate school at the University of Rochester in 2008, where I did my Ph.D in Physics and Astronomy with Eric Mamajek, studying the star formation history of nearby OB associations, finding new members of associations, and studying the properties of pre-main sequence stars. I've been an Assistant Professor of Physics at Rockhurst University since 2013, where I am now. I teach introductory physics to engineering, and pre-health care students, as well as some upper-level engineering and physics courses and squeeze in some Astronomy Research as well. Whew!


Recently, Eric Mamajek and I have completed a survey for new solar-mass (~0.7 - 1M) members of all three subgroups of Scorpius-Centaurus, the nearest site of recent massive star formation. That new work can be found here: Scorpius-Centaurus is an excellent place to learn about star formation, stellar evolution, and the formation and evolution of planetary systems because it contains thousands of stars of more-or-less the same age and chemical composition. It's also not too far away, so it is an excellent hunting ground for directly-imaged planets. In addition, the stars in Scorpius-Centaurus are at an interesting age - "young enough" to determine their ages to a meaningful degree, "young enough" so their jupiter-like planets are still puffy and therefore bright and easier to find, "young enough" so their "asteroid belts" are still producing lots of dust and are also easier to find.

I also have an active research program with undergraduates at Rockhurst University, where I teach. I always give students real projects that can (and should!) lead to publication in peer-reviewed scientific journal. I also try to make sure my students get multiple chances to present their research at conferences, both local and national/international conferences, where they can meet and talk with people who are very interested in their work.

Past and Present members of our Research Group

  • Katie Boyce - The Li depletion age of the TW Hydra Association
  • Grant Eckelkamp & Skylar Smith - Anomalous spectral types of A-type stars in the nearest OB Association
  • Megan Hyde - Age constraints on nearby OB associations based on the supernova record in the ocean crust.
  • Rachel Schaff - New members of young, nearby moving groups


    • If you have stellar spectra for spectral classification and you need a tool to help you visually compare with a dense grid of standards, you might be interested in sptool, a python-based tool that lets you navigate your grid of spectral standards with the keyboard and assist you with classification.
    • DECam synthetic colors of the BT-Settl NextGen/Phoenix models.
    • If you have de-reddened colors and you want an estimate of Teff for the star in question, you can use the calibrations based on the Infrared Flux Method with my IRFM Teff Calculator based on the 2010 paper by Casagrande, et al.

    Press Coverage:

    The research I was involved in with my collaborators moved a bit faster when I was doing research 100% of the time, so some of these stories are a bit old, but nonetheless, I am still proud of this work.