We present an image of the resolved nebular remnant of Nova Cygni 1975 (V1500 Cygni), obtained in 1987 July. The image has been enhanced by sharpening techniques, with the central star both retained and removed by point-spread-function subtraction. The median nebular radius at that time was 1″.90±0″.10, and the structure in projection was essentially that of a circular annulus. "Blob and ring" models of the ejected material, previously proposed, do not seem to match well with the actual image. If the ejection was roughly spherical, our observations coupled with the expansion velocity derived from the principal absorption spectrum imply a distance of 2.11±0.10 kpc for the nova. If the emission-line expansion velocity measured by Cohen [ApJ, 292, 90 (1985)] is used, our observations imply a distance of 1.56±0.08 kpc. We also provide flux measurements of the star-plus-nebula system at Hα + [N II] for 1983 September and 1987 July, along with monochromatic flux densities at Ha for several nearby stars.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science