Morphology and Evolution of Planetary Nebulae
نویسندگان
چکیده
منابع مشابه
Morphology and Evolution of Galactic and Magellanic Cloud Planetary Nebulae
Planetary nebulae (PNe) exist in a range of different morphologies, from very simple and symmetric round shells, to elliptical, bipolar, and even quadrupolar shapes. They present extremely complex ensembles of filaments, knots, ansae, and shell multiplicity. It is then overwhelmingly complicated to derive reasonable evolutionary paths to justify the observed shapes of PNe. The confrontation bet...
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The LMC is ideal for studying the co-evolution of planetary nebulae (PNe) and their central stars, in that the debilitating uncertainties of the Galactic PN distance scale and selection biases from attenuation by interstellar dust do not apply. We present images and analyze slit-less spectra which were obtained in a survey of Large Magellanic Cloud PNe. These data on 29 targets were obtained wi...
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The distributions of H2 1-0 S(l) emission in the young planetary nebulae BD +30°3639 and NGC 7027 show ~triking similarities: both have limb-brightened arcs of H2 emission with radii that are about twice those of ~h~ir H; II regions. The extended H2 emission in both nebulae is attributed to a photodissociation region. Thi.s implies that the neutral envelopes of these young planetaries extend we...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1993
ISSN: 0074-1809
DOI: 10.1017/s0074180900172158