¹S. Xu, ²M. Jura, ³P. Dufour, ²B. Zuckerman
¹European Southern Observatory, Karl-Schwarzschild-Straße 2, D-85748 Garching, Germany
²Department of Physics and Astronomy, University of California, Los Angeles CA 90095-1562, USA
³Institut de Recherche sur les Exoplanètes (iREx), Université de Montréal, Montréal, QC H3C 3J7, Canada

We report high-resolution spectroscopic observations of WD 1145+017—a white dwarf that was recently found to be transitted by multiple asteroid-sized objects within its tidal radius. We discovered numerous circumstellar absorption lines with linewidths of ~300 km s−1 from Mg, Ca, Ti, Cr, Mn, Fe, and Ni, possibly from several gas streams produced by collisions among the actively disintegrating objects. The atmosphere of WD 1145+017 is polluted with 11 heavy elements, including O, Mg, Al, Si, Ca, Ti, V:, Cr, Mn, Fe, and Ni. Evidently, we are witnessing the active disintegration and subsequent accretion of an extrasolar asteroid.

Reference
Xu S, Jura M, Dufour P, Zuckerman B (2016) EVIDENCE FOR GAS FROM A DISINTEGRATING EXTRASOLAR ASTEROID. The Astrophysical journal (Letters), 816 L22
Link to Article [http://dx.doi.org/10.3847/2041-8205/816/2/L22]