Revealing Structure in the HD 53143 Debris Disk

The solar analog star HD 53143 hosts a tenuous disk of cold material analogous to a more massive version of our solar system's Kuiper Belt. Puzzlingly, unlike every other debris disk observed thus far, existing low-S/N visible wavelength images of HD 53143 show that the micron-sized dust around HD 53143 does not resemble a circumstellar ring--rather, it looks like two isolated clumps of material. New ALMA observations show that the underlying distribution of larger planetesimals is indeed ring-like, but very eccentric and mis-aligned with the visible wavelength clumps. Further, the ALMA observations reveal 5-sigma excesses just interior to the circumstellar ring, suggesting structure in the planetesimal population that may be connected to the visible wavelength clumps. We propose high-S/N coronagraphic imaging of HD 53143 using HST STIS to reveal the peculiar nature of this unique debris disk and search for signs of planet-induced disk structure or collisional activity. In addition to revealing the structure of the disk, these high-S/N images will allow us to measure the optical properties of the debris disk dust to constrain its composition, size distribution, and provide critical measurements of debris disk properties that will inform future exoplanet-imaging missions.