  HD 53143 is a mature Sun-like star and host to a broad disk of dusty debris,
including a cold outer ring of planetesimals near 90 AU. Unlike most other
inclined debris disks imaged at visible wavelengths, the cold disk around HD
53143 appears as disconnected "arcs" of material, with no forward scattering
side detected to date. We present new, deeper Hubble Space Telescope (HST)
Space Telescope Imaging Spectrograph (STIS) coronagraphic observations of the
HD 53143 debris disk and show that the forward scattering side of the disk
remains undetected. By fitting our KLIP-reduced observations via forward
modeling with an optically thin disk model, we show that fitting the visible
wavelength images with an azimuthally symmetric disk with unconstrained
orientation results in an unphysical edge-on orientation that is at odds with
recent ALMA observations, while constraining the orientation to that observed
by ALMA results in nearly isotropically scattering dust. We show that the
HD53143 host star exhibits significant stellar variations due to spot rotation
and revisit age estimates for this system.
