planetary nebula


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planetary nebula

n.
A nebula, often circular or ring shaped, formed by the ejection of the outer layers from a late-stage, low-mass star.

planetary nebula

n
(Celestial Objects) an expanding shell of gas surrounding a dying star, formed from matter ejected from the star's outer layers; the gas is ionized by the remaining hot stellar core, emitting light in the process
[C18: named from its (occasional) resemblance to a planetary disc]

plan′etary neb′ula


n.
an expanding shell of thin ionized gas that is ejected from and surrounds a hot, dying star.
[1775–85]

plan·e·tar·y nebula

(plăn′ĭ-tĕr′ē)
A nebula consisting of an expanding shell of gas, mostly hydrogen, that surrounds a hot, compact central star. See more at star.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.planetary nebula - a nebula that was once thought to be a star with its planets but is now thought to be a very hot star surrounded by an expanding envelope of ionized gases that emit a fluorescent glow because of intense radiation from the starplanetary nebula - a nebula that was once thought to be a star with its planets but is now thought to be a very hot star surrounded by an expanding envelope of ionized gases that emit a fluorescent glow because of intense radiation from the star
nebula - an immense cloud of gas (mainly hydrogen) and dust in interstellar space
Translations
nebulosa planetaria
planetaarinen sumu
nébuleuse planétaire
References in periodicals archive ?
"Here we report observations, based on advances in terahertz spectroscopy and a high-altitude observatory, of the rotational ground-state transition of HeH+ at a wavelength of 149.1 micrometres in the planetary nebula NGC 7027," the researchers wrote in the study.
Only 1.8[degrees] east-northeast of M15's heart, we find the ghostly planetary nebula NGC 7094.
The Instituto de AstrofE[degrees]sica de AndalucE[degrees]a (IAA-CSIC) in Spain, the Laboratory for Space Research (LSR) of the University of Hong Kong (HKU), and an International team comprising scientists from Argentina, Mexico and Germany have discovered the unusual evolution of the central star of a planetary nebula in our Milky Way.
Like the dramatic supernova explosions of weightier stars, the death cries of the stars responsible for planetary nebulas also enrich the local interstellar environment with elements from which the next generations of stars are born.
A planetary nebula arises when an aging star with about the mass of our Sun sheds its outer layers into space.
Object Type RA Dec (J2000.0) DOLIDZE 27 Open Cluster 16h36m5 -08 [degrees]56' NGC 6218-M12 Globular Cluster 16 47 2 -01 58 NGC 6240 Galaxy 16 53 0 +02 24 NGC 6254-M10 Globular Cluster 16 57 1 -04 06 NGC 6273-M19 Globular Cluster 17 02 6 -26 16 ESO 587-SC04 Open Cluster 17 04 4 -19 27 NGC 6284 Globular Cluster 17 04 5 -24 47 B 57 Dark Nebula 17 08 3 -22 50 NGC 6309 Planetary Nebula 17 14 1 -12 55 NGC 6333-M9 Globular Cluster 17 19 2 -18 31 B 78 Dark Nebula 17 21 1 -26 47 B 72 Dark Nebula 17 23 5 -23 38 BARNARD'S STAR Star 17 57 8 +04 44 Object Mag.
A planetary nebula is the remnant of a star like our Sun that has finished its days by throwing off its hydrogen in a bubble around it,and now exists as a small hot white dwarf star at the centre.
This image of Helix, the nearest planetary nebula to the sun, was taken by the Hubble Space Telescope.
In this report, we present photoelectric magnitude measurements of the planetary nebula NGC 6210.
The transition from red giant to planetary nebula - a gaseous envelope surrounding a "white dwarf" star that has collapsed in on itself - took only a few thousand years.
6 After a billion years, the red giant ejects its outer layer as a planetary nebula, leaving a collapsed core at the center.