Results 81 to 90 of about 27,938 (255)
Lawnmower Poetry and the Poetry of Lawnmowers
Critical Quarterly, EarlyView.
Francesca Gardner
wiley +1 more source
Northwest Africa 13489: A Strongly Metamorphosed Ungrouped Carbonaceous Chondrite
Meteoritics &Planetary Science, EarlyView.Abstract NWA 13489 is a meteorite that has been classified as a brachinite. Brachinites are olivine‐rich primitive achondrites representing residual products after a variable degree of silicate melt extraction on a barely differentiated, noncarbonaceous asteroid.
T. Cuppone +5 more
wiley +1 more source
Distances of Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1993 One of the most fundamental physical parameter in astronomy is the distance to the objects we detect in the universe. For many classes of astronomical objects, accurate and proven methods have been developed to determine their distances. Such classes of objects include stars within ∼100 pc from the sun, binary stellar systems, variable stars, stellar ...
openaire +2 more sources
Mapping NGC 7027 in New Light: CO+ and HCO+ Emission Reveal Its Photon- and X-Ray-dominated Regions
The Astrophysical Journal, 2022 The young and well-studied planetary nebula (PN) NGC 7027 harbors significant molecular gas that is irradiated by luminous, pointlike UV (central star) and diffuse (shocked nebular) X-ray emission.
Jesse Bublitz +9 more
doaj +1 more source
Binary Stars in Planetary Nebulae [PDF]
, 2013 When a star like the sun dies, it swells into a red giant and then expels its outer layers to form a planetary nebula. Eventually the outer layers leave the leftover core and it becomes a white dwarf.
Rotter, Hannah
core +1 more source
Unveiling the structure of the planetary nebula M 2-48: Kinematics and physical conditions [PDF]
, 2002 The kinematics and physical conditions of the bipolar planetary nebula M 2-48 are analysed from high and low dispersion long-slit spectra. Previous CCD narrow-band optical observations have suggested that this nebula is mainly formed by a pair of ...
A. Raga +37 more
core +2 more sources
Meteoritics &Planetary Science, EarlyView.Abstract Meteorites are easily contaminated at the Earth's surface by microbial activity. Here, DNA extracts from two meteorite specimens and samples from curation laboratory surfaces are analyzed with amplicon sequencing, to understand microbial communities that contaminate meteorites and that may be resident in curation facilities.
Libby D. Tunney +4 more
wiley +1 more source
Progenitors of Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1989 Over the past decade, we have come to realize that mass loss on the asymptotic giant branch (AGB) plays a significant role in the formation of planetary nebulae (PN). Mass ejected during the AGB can now be observed in haloes of PN and we believe that the main shell of PN is formed by the interaction of this material with a later-developed central-star ...
openaire +2 more sources
Measurements on Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1974 165 planetary nebulae south of +27° declination have been observed with the Parkes 64 m telescope. These nebulae were chosen to include most of those for which Hβ flux densities are available. Radio positions and flux densities (generally with probable errors of only a few millijanskies) obtained from the survey must represent the most reliable and ...
D. K. Milne, L. H. Aller
openaire +2 more sources
Magnesium phosphate in the Cold Bokkeveld (CM2) carbonaceous chondrite
Meteoritics &Planetary Science, EarlyView.Abstract Hydrous Mg‐phosphate was first described from astromaterials in particles returned from the C‐type asteroid Ryugu, and has subsequently been found in samples of the B‐type asteroid Bennu and CI1 carbonaceous chondrites. This phase may have been highly significant as a source of bioessential compounds for early Earth.
Martin R. Lee +2 more
wiley +1 more source