Results 161 to 170 of about 191,657 (282)
GalaxiesWe present a brief review of the formation and evolution of hydrogen-deficient central stars of planetary nebulae. We include a detailed description of the main observable features of both the central stars and their surrounding nebulae and review their ...
Marcelo M. Miller Bertolami
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Distances to Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1989 Finding distances to planetary nebulae remains a frustrating undertaking, but significant progress has been made over the past several years. This review covers primarily work done on distances since 1980, with some references to earlier papers. Some interesting new methods have been tried recently and some methods that have been used for years have ...
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New insights into the physical state of gaseous nebulae [PDF]
The impact of knowledge of H II regions, planetary nebulae and supernova remnants due to International Ultraviolet Explorer is examined. The more relevant aspects related to the physical conditions of gaseous nebulae are reviewed.
Peimbert, M.
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The Parallax of the Planetary Nebulae N. G. C. 7662 [PDF]
, 1917 A. van Maanen
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Nuclei of Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1973 In 1969 Aller and I collected information about the spectra of emission-line nuclei of planetary nebulae. (See also Aller, 1967, for classification of both emission and absorption spectra.) We classified them and compared them to the spectra of Population I stars. Our idea was to follow this general classification by detailed observation and comparison
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The mystery of unidentified infrared emission bands. [PDF]
Astrophys Space Sci, 2022 Kwok S.
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Electron Temperatures and Electron Densities in Planetary Nebulae [PDF]
, 1954 M. J. Seaton
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Dust in planetary nebulae [PDF]
Proceedings of the International Astronomical Union, 2016 AbstractInfrared spectra from the Spitzer Space Telescope trace the evolution of carbon-rich dust from the asymptotic giant branch (AGB) to young planetary nebulae (PNe). On the AGB, amorphous carbon dominates the dust, but SiC and MgS also appear. In more evolved systems with warmer central stars, the spectra reveal the unidentified 21 μm feature ...
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