Results 171 to 180 of about 245,593 (320)
Properties of Proto--Planetary Nebulae [PDF]
arXiv, 2000 This review describes some general properites of proto-planetary nebulae with particular emphasis on the recent work of morpholgical studies. The weight of observational evidence shows that proto-planetary nebulae (PPNe) are most certainly axisymmetric like planetary nebulae.
arxiv
Confirmation of SBS 1150+599A As An Extremely Metal-Poor Planetary Nebula
, 2002 SBS 1150+599A is a blue stellar object at high galactic latitude discovered in the Second Byurakan Survey. New high-resolution images of SBS 1150+599A are presented, demonstrating that it is very likely to be an old planetary nebula in the galactic halo,
Alberto Noriega-Crespo +19 more
core +1 more source
Catalogues of Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1989 Firstly, the general requirements concerning catalogues are studied for planetary nebulae, in particular concerning the objects to be included in a catalogue of PN, their denominations, followed by reflexions about the afterlife and computerized versions of a catalogue.
openaire +2 more sources
Planetary Nebulae in the Magellanic Clouds: Probing Stellar Evolution and Populations [PDF]
arXiv, 2002 This review contains: (1) the scientific motivations for studying Planetary Nebulae in the Magellanic Clouds; (2) a review of this field of study, from the origins to the most recent results, focusing on the papers that have been published since the last IAU Symposium on Planetary Nebulae; (3) a review of the Hubble contribution to the field, from the ...
arxiv
Gallery of Planetary Nebula Spectra
, 2006 We present the Gallery of Planetary Nebula Spectra now available at http://oit.williams.edu/nebulae The website offers high-quality, moderate resolution (~7-10 A FWHM) spectra of 128 Galactic planetary nebulae from 3600-9600 A, obtained by Kwitter, Henry,
Henry, Richard B. C., Kwitter, Karen B.
core +3 more sources
Ionization-bounded and Density-bounded Planetary Nebulae [PDF]
arXiv, 2009 Planetary nebulae (and in general any photoionized region) can be classified as ionization-bounded or density-bounded. It is important to determine in which case is the planetary nebula studied to be able to estimate from nebular observations, for example, the total rate of ionizing photons produced by the central star.
arxiv
Fe/Ni ratio in the Ant Nebula Mz 3
, 2006 We have analyzed the [Fe II] and [Ni II] emission lines in the bipolar planetary nebula Mz~3. We find that the [Fe II] and [Ni II] lines arise exclusively from the central regions.
Liu, X. -W., Zhang, Y.
core +2 more sources
Origin of Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1967 My interest in the origin of planetary nebulae goes back to 1967 when I proposed that the envelopes of giants with degenerate carbon-helium cores were dynamically unstable and would be completely ejected to form a planetary nebula. Essentially the same proposal was made almost simultaneously by Lucy (1967) and Paczyński (1967).
openaire +3 more sources
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 ...
openaire +2 more sources
Workshop on the Origins of Solar Systems [PDF]
Topics addressed include: interstellar chemistry and primitive bodies; astronomical measurements and nebula models; solar nebula models and meteorite; and planetary accumulation and ...
Nuth, Joseph A., Sylvester, Paul
core +1 more source