Bazsites.com Planetary Nebulae

Directory Topics

Planetary Nebulae - A short discussion, part of a web page on plasmas.
Variability of Planetary Nebula Central Stars - No description
Planetary Nebulae Gallery - A data table with links to images.
ARVAL Catalog of Bright Planetary Nebulas - A text table, with name, size, magnitude, area, NGC number, type, RA, dec., and visual quality.
Hubble's Planetary Nebula Gallery (PRC97-38b) - No description
Planetary Nebula Sampler - No description
List of Common Deep Sky Catalogs - General, supernova remnants, planetary nebulae, diffuse nebulae, dark nebulae, open clusters, globular clusters, galaxies, clusters of galaxies, double stars, and references.
Images from the Night Sky - Galaxies, emission nebulae, planetary nebulae, and earth images, and informational techniques and tips.
Best Images of the Advanced Observing Program - Solar system, diffuse nebulae, galaxies, planetary nebulae, star clusters, and supernovae remnants images.
Astronomical Pictures of Galaxies Photos - Astronomy Images - Astronomy Pictures with 1300 Astronomical Images of Spiral and Elliptical Galaxies, Planetary Nebulae Astronomy Images and Astronomical Photos of Solar System Planets.

List of planetary nebulae - ==Notes==
Fast Low-Ionization Emission Region - Fast Low-Ionization Emission Regions (FLIERs) are volumes of gas with low ionization near the symmetry axis of many planetary nebulae. Their outflow speeds are significantly higher than the nebulae in which they are embedded, and their ionizations are much lower.
Collisional excitation - Collisional excitation is a process which gives rise to spectral lines in the spectra of astronomical objects such as planetary nebulae and H II regions.
Mira variable - ... a class of pulsating variable stars characterized by very red colors, pulsation periods longer than 100 days, and light amplitudes greater than one magnitude. They are red giant stars in the very late stages of stellar evolution (the asymptotic giant branch) that will expel their outer envelopes as planetary nebulae and become white dwarfs within a few million years.
Cloud - A cloud is a visible mass of condensed droplets, frozen crystals suspended in the atmosphere above the surface of the Earth or another planetary body, such as a moon. (Clouds can also occur as masses of material in interstellar space, where they are called interstellar clouds and nebulae.