Results 81 to 90 of about 191,657 (282)

Gaia DR2 Distances to Planetary Nebulae

Galaxies, 2020
The aim of this work is to examine distances to planetary nebulae (PNe) together with other properties that were derived from them, using the astrometry of Gaia Data Release 2 (DR2).
Iker González-Santamaría, Minia Manteiga, Arturo Manchado, Ana Ulla, Carlos Dafonte   +4 more
doaj   +1 more source

Low-ionization structures in planetary nebulae – I. Physical, kinematic and excitation properties [PDF]

, 2015
Though the small-scale, low-ionization knots, filaments and jets (LISs) of planetary nebulae (PNe) are known for ~30yr, some of their observational properties are not well established.
S. Akras, D. R. Gonçcalves
semanticscholar   +1 more source

Business ethics, law and zemiology: The criminology of social and environmental harm

Business Ethics, the Environment &Responsibility, EarlyView.
Abstract This speculative paper introduces zemiology, an extension of radical criminology which explores why many ‘crimes’ are not ‘illegal’ by focussing on the problem of ‘social harm’. Zemiology insists that we should begin with social or environmental problems, and not allow their foreclosure by the distraction of whether a particular practice is ...
Robin Klimecki, Martin Parker
wiley   +1 more source

In Search of Possible Associations between Planetary Nebulae and Open Clusters

, 2007
We consider the possibility of cluster membership for 13 planetary nebulae that are located in close proximity to open clusters lying in their lines of sight.
Akhundova G. V., Andrews A. D., Barkhatova K. A., Bertelli G., Burki G., Cahn J. H., Cazetta J. O., Cuisinier F., Cutri R. M., Dambis A. K., Daniel J. Majaess, David G. Turner, David J. Lane, Glushkova E. V., Glushkova E. V., Hasegawa T., Jennens P. A., Kholopov P. N., Koester D., Kwok S., Mal'kov Y. F., Mallik D. C. V., Mermilliod J.-C., Mermilliod J.-C., Meynet G., Moffat A. F. J., Moitinho A., Neckel Th., Osterbrock D. E., Pena M., Peton-Jonas D., Svolopoulos S. N., Tifft W. G., Turner D. G., Tylenda R., Walker A. R., Weidemann V., Zijlstra A. A., Ziznovsky J.   +38 more
core   +1 more source

Planetary Nebulae Formation [PDF]

Highlights of Astronomy, 1980
It is a well accepted idea that Planetary Nebulae ( P.N. ) formation is due to mass ejection from red giant envelopes.According to the original model, as was proposed by Roxburgh and Lucy in 1967, and established about a year later by Paczynski and Ziolkowski (1968), red giant envelopes become dynamically unstable above a certain boundary luminosity ...
Z. Barkat, Y. Tuchman, N. Sack
openaire   +2 more sources

THE PROGENITORS AND LIFETIMES OF PLANETARY NEBULAE [PDF]

, 2015
Planetary nebulae (PNe) are among the most spectacular objects produced by stellar evolution, but the exact identity of their progenitors has never been established for a large and homogeneous sample. We investigate the relationship between PNe and their
C. Badenes, D. Maoz, R. Ciardullo
semanticscholar   +1 more source

THE MASSES OF THE IONIZED GAS OF PLANETARY NEBULAE ENVELOPES IN LARGE MAGELLANIC CLOUD

Odessa Astronomical Publications, 2013
The masses of ionized gas in the shells of planetary nebulae which belong in the Large Magellanic Cloud are calculated by three different ways. The value of mass is calculated for the cases: 1) spherical, 2) elliptical forms of envelopes and 3) commonly ...
V. Holovatyy, A. Demchyna
doaj   +1 more source

The Search for Binaries in Post-Asymptotic Giant Branch Stars: Do Binary Companions Shape the Nebulae? [PDF]

Journal of Astronomy and Space Sciences, 2012
Binary companions are often invoked to explain the axial and point symmetry seen in the majority of planetary nebulae and proto-planetary nebulae (PPNs).
Bruce J. Hrivnak
doaj   +1 more source

Planetary systems and real planetary nebulae from planet destruction near white dwarfs [PDF]

, 2015
Abnormal accumulation of TDP-43 and FUS proteins is found in a neurodegenerative disease amyotrophic lateral sclerosis. Here the authors show by modelling the disease in worms that these proteins activate local and distal immune responses, and blocking ...
Ealeal Bear, N. Soker
semanticscholar   +1 more source

Evaluating Investment in Space Programs: A Case for Theoretical Pluralism

Financial Accountability &Management, EarlyView.
ABSTRACT A perennial question repeatedly asked since the early Mercury (USA) and Salyut (then Soviet Union) space programs has been variations on the theme of “how can the cost of space exploration be justified?” This question—which in broad terms constitutes the research question considered in this paper—continues to be directed toward space agencies ...
Basil P. Tucker, Hank C. Alewine
wiley   +1 more source