The BU White Dwarf Group

Boston Skyline

Welcome to the home page of the BU White Dwarf group, headquartered a few blocks from Fenway Park in Boston, MA, USA.

Our research focuses on white dwarf stars and their connection to the endpoints of stars, binary, and planetary systems. Our work is supported by Boston University, the Institute for Astrophysical Research, the National Aeronautics and Space Administration (NASA), the National Science Foundation (NSF), and the Massachusetts Space Grant Consortium.


Recent news and group updates:
Research updates can be found below and on the news page.

A class of supernova survivors

By JJ HermesFebruary 1st, 2020

Group members and collaborators have discovered a new class of zombie stars that are likely the shattered remnants of thermonuclear supernova that did not fully disrupt the white dwarf! Led by Roberto Raddi at Dr.Karl-Remeis-Sternwarte Bamberg, we have now published at least three more members of this new class of star named after the prototype LP 40-365.

The research is well summarized by Shannon Hall writing in Scientific American: This “newly discovered class of odd stars appears to have persevered through supernova explosions — providing a rare glimpse into these astrophysical catastrophes.” Another summary is detailed in a Twitter thread: https://twitter.com/jotajotahermes/status/1096054102327525376.

White dwarf core crystallization

By JJ HermesFebruary 1st, 2020

Last year we published in Nature the most comprehensive evidence that white dwarf stars, at the end of their lives, solidify into crystals! The research is best summarized in this quote from Deborah Netburn of The Los Angeles Times: “New research suggests that long after our roiling, boiling life-giving star runs out of fuel, it will slowly transform into a cold, dead, super-dense crystal sphere about the size of Earth that will linger like a translucent tombstone for close to eternity.”

An artist's illustration of a white dwarf in the process of solidifying (credit University of Warwick/Mark Garlick).

The manuscript was led by Pier-Emmanuel Tremblay at the University of Warwick, and was made possible by the excellent data from the second data release of the Gaia mission. Another write-up of the results can be found here: https://twitter.com/jotajotahermes/status/1083068794455707648.