Ultraviolet Imaging Polarimetry of the Peculiar Seyfert 2 Galaxy Markarian 477

We present the results of UV imaging polarimetry of the Seyfert 2 galaxy Mrk 477 taken by the Faint Object Camera on board the Hubble Space Telescope (HST). From a previous HST UV image (λ ~ 2180 A), Mrk 477 has been known to have a pointlike bright UV hot spot in the central region, peculiar among nearby Seyfert 2 galaxies. There are also claims of UV/optical variability, unusual for a Seyfert 2 galaxy. Our data show that there is an off-nuclear scattering region ~06 (~500 pc) northeast from the hot spot. The data, after the subtraction of the instrumental effect due to this bright hot spot region, might indicate that the scattered light is also detected in the central 02 radius region and is extended to a very wide angle. The hot spot location is consistent with the symmetric center of the position angle pattern, which represents the location of the hidden nucleus, but our data do not provide a strong upper limit to the distance between the symmetric center and the hot spot. We have obtained a high spatial resolution color map of the continuum that shows that the nuclear spiral arm of 04 scale (~300 pc) is significantly bluer than the off-nuclear mirror and the hot spot region. The nature of the hot spot is briefly discussed.