A New ALMA View of the HD 53143 Debris Disk

Debris disks provide a fossil record of the earlier planet formation process. In these systems, planetesimals (asteroids and comets) are eroded through collisions. The structure of these remnant belts is sculpted by planets, and can be imaged at high resolution to reveal a rich dynamical history. HD 53143 is a Sun-like G9V star at 18.3 pc with an estimated age of ~1 Gyr. Previous HST STIS coronagraphic imaging did not detect flux along the minor axis of the disk which was interpreted as resulting from a face-on geometry with two “clumps” of dust. We present the first image of this intriguing system at millimeter wavelengths taken with the Atacama Large Millimeter/submillimeter Array (ALMA) at 1.3 mm (Band 6). By fitting models directly to the millimeter visibilities, we are able to robustly constrain the structure of the disk. These new observations revealed that HD 53143 is instead eccentric, demonstrating a clear apocenter glow. We compare the millimeter and micron-sized dust distribution as traced by ALMA and HST, respectively, and consider potential misalignments that might inform our understanding of previous dynamics in this system.