The Variable Nebula in Corona Australia (N.G.C. 6729). R.A. 18h 52m. Dec. 37 8'. (Plate 13.)
نویسندگان
چکیده
منابع مشابه
The tetra - lobed planetary nebula NGC 1501
Direct imagery and long-slit, spatially resolved echellograms of the high excitation planetary nebula NGC 1501 allowed us to study in detail the expansion velocity field, the physical conditions (electron temperature, electron density, ionization) and the spatial distribution of the nebular gas. An electron temperature of 11500 K and a turbulence of 18 km s−1 are derived by comparing the Hα and...
متن کاملThe tails in the Helix Nebula NGC 7293
Aims. We have examined a stream-source model for the production of the cometary tails observed in the Helix Nebula NGC 7293 in which a transonic or moderately supersonic stream of ionized gas overruns a source of ionized gas. We have compared the velocity structures calculated with the available observational data. We have also investigated the suggestion that faint striations visible in the ne...
متن کاملAstronomy & Astrophysics Abundances in the planetary nebula NGC 6210
The spectra of the planetary nebula NGC 6210 is reanalysed using spectral measurements made in the mid-infrared with the Spitzer Space Telescope and the Infrared Space Observatory. The aim is to determine the chemical composition of this object. We also make use of IUE and ground based spectra. Abundances determined from the mid-infrared lines, which are insensitive to electron temperature, are...
متن کاملThe ISO spectrum of the planetary nebula NGC 6302
The spectrum of the planetary nebula NGC 6302 is presented, as it was observed by the ISO short-wavelength spectrometer. The IUE spectrum observed at the same position with the same aperture is also presented.
متن کاملThe central star of the Planetary Nebula NGC 6537
The fact that Space Telescope WFPC2 images of the planetary nebula NGC 6537 fail to show the central star is used to derive a limit to its magnitude: it is fainter than a magnitude of 22.4 in the visible. This is used to derive a lower limit to the temperature of the star. The Zanstra temperature is at least 500 000 K. The Energy Balance temperature is found to be consistent with this value, as...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1916
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/76.8.645