A Multiwavelength Study of IC 63 and IC 59

IC 63 and IC 59 are two nearby arc-shaped nebulae with relatively simple geometries and minimal obscuring material. The two regions, in spite of a similar projected distance from their ionizing star, have very different observational properties, both in continuum emission and in the presence and strength of line emission from molecular species. This paper conducts a multiwavelength study of the two regions using archived data from a variety of sources, including the Canadian Galactic Plane Survey and the Infrared Space Observatory. The multiwavelength morphology and structure of the two nebulae are studied in detail, particularly the ionization fronts in IC 63. The possibility of triggered star formation in IC 63 is investigated and determined to be spurious. H₂ and polycyclic aromatic hydrocarbon emission is detected in both IC 63 and IC 59, confirming the presence of molecular hydrogen in IC 59. The averaged line ratios are similar in the two regions, but variations are seen within each region. Temperatures and densities were calculated from the S(3) and S(5) pure rotational lines of molecular hydrogen. We derived a temperature of 630 K in IC 63, comparable to previous results, and a column density of 5.8 × 10¹⁷ cm^-2, somewhat lower than previous values. New results for IC 59 show values of 590 K and 3.4 × 10¹⁷ cm^-2, slightly cooler and with lower column density than IC 63. The contrast in appearance between IC 63 and IC 59 is consistent with a difference in actual (rather than projected) distances and a small variation in temperature and column density.