Wesleyan portrait of William  Herbst

William Herbst

John Monroe Van Vleck Professor of Astronomy, Emeritus


BA Princeton University
MAA Wesleyan University
MSC University of Toronto
PHD University of Toronto

William Herbst

William Herbst is an astronomer interested in star formation, planet formation, meteorites, chondrules, T Tauri stars and the formation of the Earth. He observes and interprets the light variations of T Tauri stars, objects that are similar in mass to the Sun but at an age (< 10 Myr) when their planetary systems were still forming. This research makes use of telescopes at Van Vleck Observatory (VVO) on the Wesleyan campus, other facilities around the world, and space telescopes. An object of particular interest whose unique behavior was discovered at VVO is known as KH 15D, and has been shown to be a "proto-Tatooine" object -- that is, a binary star system orbited by a ring of material that may one day consolidate to form planets orbiting a double star like the fictional home world of Luke and Anakin Skywalker in Star Wars. More recently, has become interested in chondrules and chondritic meteorites, which are the most primitive samples of the solar nebula that reach the Earth's surface on their own. In collaboration with James P. Greenwood of Wesleyan's E&ES department, he has developed a theory of chondritic meteorite formation that addresses a long-standing problem in cosmochemisty, the origin of the chondrules. Their theory correctly predicted the density of the rocks on Ryugu, the first asteroid from which a substantial sample of rocks was returned, and also correctly predicted that these rocks would contain few, if any, chondrules. Details may be found within the articles listed on his Google Scholar page.

Professor Herbst grew up in southern New Jersey and was an undergraduate at Princeton University, where he majored in Astrophysics and graduated with High Honors. His undergraduate research advisors were Jeremiah Ostriker and James Gunn. He received his Ph.D. in 1974 from the University of Toronto, where his research advisors were Rene Racine and Sidney van den Bergh. He taught for two years at York University in Toronto and then accepted a position in Washington, D. C., as a Carnegie Fellow at the Department of Terrestrial Magnetism (DTM), a branch of the Carnegie Insitution. His mentor at DTM was Vera Rubin. In 1978, he joined the faculty at Wesleyan University where he rose to the rank of Professor and was the John Monroe Van Vleck Professor of Astronomy from 1991 until his retirement in 2021. His current title is John Monroe Van Vleck Professor of Astronomy, Emeritus.

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Professor Herbst may be contacted through email.