Institute of Astronomy

Comparing asteroids, moons, planets and comets as possible progenitors of the pollution observed in white dwarf atmospheres

SpeakerTalk DateTalk Series
Dimitri Veras28 July 2014Across HR 2014 Talks


Abundant metal pollution in white dwarf atmospheres primarily arises from circumstellar material and not the interstellar medium. Although well-characterised on an element-by-element basis, this rocky and sometimes watery material has largely unknown origins, and may be consistent with asteroids, moons, planets or comets. Here I interpret each alternative from a dynamical context, illustrating the resulting types of orbits we may expect from late-stage dynamical instabilities, and the frequency of collisions or near-collisions with white dwarfs. I identify the sometimes significant challenges in modeling each case analytically and numerically, and conclude by detailing the constraints each case can place on the formation and early evolution of planetary systems through full-lifetime simulations across all phases of stellar evolution.