Results 11 to 20 of about 7,989 (218)
Publications of the Astronomical Society of the Pacific, 1926 Donald H. Menzel
openalex +3 more sources
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
openaire +5 more sources
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.
A. P. Healy, P. J. Huggins
openaire +2 more sources
Intracluster Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 2003 We review the progress of research on intracluster planetary nebulae (IPN). In the past five years, hundreds of IPN candidates have been detected in the Virgo and Fornax galaxy clusters and searches are also underway in poorer galaxy groups. From the observations to date, and applying the known properties of extragalactic planetary nebulae, the ...
openaire +6 more sources
Preface of “Asymmetric Planetary Nebulae 8e”
Galaxies, 2022 Planetary nebulae (PNe) are the progeny of low- and intermediate-mass stars, at the exact time in their late evolution when they eject their hydrogen-rich envelopes and start their transition towards white dwarfs [...]
Martin A. Guerrero +2 more
doaj +1 more source
X-ray Shaping of Planetary Nebulae
Galaxies, 2018 The stellar winds of the central stars of planetary nebulae play an essential role in the shaping of planetary nebulae. In the interacting stellar winds model, the fast stellar wind injects energy and momentum, which are transferred to the nebular ...
Martín A. Guerrero
doaj +1 more source
Planetary Nebulae as Sources of Chemical Enrichment of the Galaxy
Frontiers in Astronomy and Space Sciences, 2022 During the late asymptotic giant branch (AGB) phase of stellar evolution, the element carbon is created through the triple-α nuclear reaction. This is followed by the synthesis of other heavy elements via neutron capture in the core and the dredge-up of ...
Sun Kwok, Sun Kwok
doaj +1 more source
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
doaj +1 more source