Results 1 to 10 of about 583 (162)
Binary Central Stars of Planetary Nebulae
Galaxies, 2020 It is now clear that a vast majority of intermediate-mass stars have stellar and/or sub-stellar companions, therefore it is no longer appropriate to consider planetary nebulae as a single-star phenomenon, although some single, isolated stars may well ...
David Jones
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Annual Review of Astronomy and Astrophysics, 1993 The progress in the search for proto-planetary nebulae (PPN) in the last 5 years is reviewed. An observational definition of PPN is developed and a list of current PPN candidates is given. The optical, infrared, and radio properties of PPN are summarized and compared with theoretical models.
Sun Kwok
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The Formation of Fullerenes in Planetary Nebulae
Galaxies, 2018 In the last decade, fullerenes have been detected in a variety of astrophysical environments, with the majority being found in planetary nebulae. Laboratory experiments have provided us with insights into the conditions and pathways that can lead to ...
Jan Cami +4 more
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Galaxies, 2018 The increase in discovered close binary central stars of planetary nebulae is leading to a sufficiently large sample to begin to make broader conclusions about the effect of close binary stars on common envelope evolution and planetary nebula formation ...
Todd Hillwig
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Lessons from the Ionised and Molecular Mass of Post-CE PNe
Galaxies, 2022 Close binary evolution is widely invoked to explain the formation of axisymmetric planetary nebulae after a brief common envelope phase. The evolution of the primary would be interrupted abruptly, its still quite massive envelope being fully ejected to ...
Miguel Santander-García +4 more
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PHL 932: When Is a Planetary Nebula Not a Planetary Nebula? [PDF]
Publications of the Astronomical Society of Australia, 2010 AbstractThe emission nebula around the subdwarf B (sdB) star PHL 932 is currently classified as a planetary nebula (PN) in the literature. Based on a large body of multi-wavelength data, both new and previously published, we show here that this low-excitation nebula is in fact a small Strömgren sphere (Hii region) in the interstellar medium around this
Parker, Quentin A. +3 more
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The Astrophysical Journal, 1987 We report the first detection of millimeter CO emission in two highly evolved planetary nebulae: NGC 6720 and NGC 7293. The CO is a useful probe of the structure and kinematics of the molecular gas in the nebulae, and provides an estimate of the mass of material which remains un-ionized by the central star.
P. J. Huggins, A. P. Healy
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Shaping of Planetary Nebulae by Exoplanets
Galaxies, 2020 (1) Background: We investigate the hypothesis that exoplanet engulfment can help explain the observed non-spherical planetary nebula population, as a complementary shaping mechanism to the binary hypothesis.
Nicola Keaveney +2 more
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Observing the signatures of AGB s-process nucleosynthesis in planetary nebulae: An origins story
Frontiers in Astronomy and Space Sciences, 2022 I relate an anecdotal history of the beginnings of a new initiative in studies of the chemical composition of planetary nebulae: namely, investigating abundances of elements beyond the iron-peak through infrared spectroscopy.
Harriet L. Dinerstein
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On the Origin of Planetary Nebulae [PDF]
Progress of Theoretical Physics, 1962 A hypothesis that planetary nebulae originate from red giants when tl:e helium burning begins in the degenerate helium core is proposed and examined quantitatively. It is assumed that the shock wave is generated by the rapid core expansion which is caused by the removal of degeneracy at the helium core.
Sakashita, S., Tanaka, Yasuo
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