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Basic Info

Name: William Herbst

Title: John Monroe Van Vleck Professor of Astronomy

Institution: Wesleyan University

Location: Middletown, CT

Family: Two children: John and Peter. One surrogate grandchild Sam, son of Marty and Jim.

Sport: Tennis, ~4.25 player

Hobby: Photography


Email: wherbst_at_wesleyan.edu

Telephone: 860-685-3672


Research: T Tauri stars, star and planet formation, protoplanetary disks

Teaching: Intro Astronomy, Planets, Astronomical Pedagogy, Stellar Astrophysics, The Universe, GLSP

Professional Service: NOAO Visiting Committee, PI for NSF/REU grant supporting the Keck Northeast Astronomy Consortium

Wesleyan Service: Advisory & Merit Committees

Outreach: Director of Project ASTRO-CT


William Herbst

I am a professional astronomer and John Monroe Van Vleck Professor of Astronomy at Wesleyan University in Middletown, CT, where I have been employed since 1978. My research interests are in the field of star and planet formation. My Ph.D. thesis work at the University of Toronto involved a study of stars in southern reflection nebulae and led to the discovery of a good example of supernova-induced star formation -- an association of reflection nebulae known as CMa R1. This is of particular interest because isotopic evidence in meteorites suggests that radioactive material from a nearby supernova was present in our own solar system as the planets were forming. Most of this work was done while I was a Carnegie Fellow at the Carnegie Institution of Washington’s Department of Terrestrial Magnetism in collaboration with George Assousa. Two papers that report this work for professional and semi-professional audiences are:

Observational Evidence for Supernova-Induced Star Formation - CMa R1

Herbst, W. & Assousa, G. E.; The Astrophysical Journal 217, 473 (1977)

Supernovas and Star Formation

Herbst, W. & Assousa, G. E.; Scientific American 241, 138 (1979)

Since arriving at Wesleyan I have used the 0.6m Perkin telescope on campus to monitor T Tauri stars, young stars thought to be similar to the Sun but at an evolutionary stage before the planets have fully formed. I have involved several dozen students in this work and we have made a number of discoveries, including the fact that the rotation period distribution of stars in young clusters is bimodal. It is now understood that this results from a magnetic interaction between the forming stars and their accretion disks that tends to slow their spin rate. A few of the more important papers on T Tauri variability and rotation are as follows:

Catalogue of UBVRI Photometry of T Tauri Stars and Analysis of the Causes of their Variability  Herbst, W. et al.; The Astronomical Journal 108, 1906 (1994)

Rotation Periods of Stars in the Orion Nebula Cluster: The Bimodal Distribution

Choi, P. I. & Herbst, W., The Astronomical Journal 111, 283, (1996)

Rotational Evolution of Solar-like Stars in Clusters from Pre-Main Sequence to Main Sequence: Empirical Results

Herbst, W. & Mundt, R., The Astrophysical Journal 633, 967 (2005)

In 1996, as part of our T Tauri monitoring program my student Kristin Kearns and I discovered a unique object now known as KH 15D. It “winked” on and off, changing brightness quite quickly and dramatically on a 48-day cycle. The object is now understood as a binary system embedded in a circumstellar disk or ring that blocks part of the orbit from our perspective. Amazingly, the occulting disk is precessing so that more and more of the orbit of the stars is blocked and in mid-2008 the system will be permanently in the “off” state, visible only by reflected light. This, of course, will provide an excellent opportunity to learn more about the circumstellar matter that is causing the reflection. Two important papers on this object are:

Fine Structure in the Circumstellar Environment of a Young, Solar-like Star: The Unique Eclipses of KH 15D

Herbst, W. et al., Publications of the Astronomical Society of the Pacific 114, 1167

Reflected Light from Sand Grains in the Terrestrial Zone of a Protoplanetary Disk

Herbst, W. et al., Nature 452, 194, (2008)

For a complete list of my publications from the NASA Astrophysical Data System click here.

At Wesleyan I have taught a variety of astronomy courses at different levels and have also been a regular contributor to the Graduate Liberal Studies Program. In 2003 I received a Binswanger Award for Excellence in Teaching from the Alumni Association of Wesleyan University, for which I am extremely grateful. Mentoring students in research is, of course, an important part of my teaching responsibilities at Wesleyan and I have been fortunate to have worked with a large number of excellent students. Catrina Hamilton is my only Ph.D. student (in Physics, since Astronomy does not offer a Ph.D.) and she is currently a professor in the Department of Physics and Astronomy at Dickinson College. I have directed ~15 MA theses and ~30 BA theses, as well as dozens of summer research students. Some former students who remain in the field of astronomy include Jon Holtzman at New Mexico State U., Andy Layden at Bowling Green State U., Phil Choi at Pomona College and Jenny Konon at the U.S. Coast Guard Academy. Twp who have left astronomy but made an impact are John Booth, a veteran of many South Pole winters, and John Filhaber a vice-president at Zygo Corp.

My contributions to the professional community have included service on many review and visiting committees for NASA, NSF and NOAO, as well as a number of colleges and universities. I am the PI on an NSF/REU grant that supports the Keck Northeast Astronomy Consortium and Director of Project ASTRO-CT. At Wesleyan I have served as Chair of the Astronomy Department and Director of Van Vleck Observatory and on many faculty committees, including the Advisory Committee. The links above are to pages that provide more detailed information.