High-resolution images of the Ring Nebula taken with the Subaru telescope

We present high-resolution images of the Ring Nebula in the H alpha, V, and B bands taken with the Subaru telescope. The H alpha image reveals the fin e structure of the inner and outer halos in unprecedented detail. The inner most part of the inner halo just outside of the main ring may be identified as a new component in terms of the surface brightness hierarchy seen in th e Ring Nebula. A filamentary structure consisting of loops and knots, which gives a petal-like appearance to the inner halo, is also seen in this new component. The outer halo is found to show a limb-brightened knotty structu re similar to the inner halo, but at much fainter levels. The typical size of the knots, however, is clearly different between the two halos. The medi an size measured on the H alpha image is 1." 2 and 3." 2 in the inner and o uter halos, respectively. The corresponding lifetime, which is defined by t he size divided by the thermal velocity, is 400 years and 1200 years. The t ricolor image was made with H alpha, Sr, and B images after being sharpened by the maximum-entropy method. The image shows the fine structure of the m ain ring and the enhanced bands of emission running across the central hole with a resolution comparable to the image taken with the Hubble Space Tele scope. The features newly found in the present images may give some support , but more challenges, to the unified model proposed by Guerrero et al.