Results 111 to 120 of about 212,521 (235)
Kinematics of Molecular Hydrogen Emission from Planetary and Pre-planetary Nebulae [PDF]
arXiv, 2000 We report results from a program of high-resolution spectral mapping of rotational H_2 emission from bipolar planetary and pre-planetary nebulae. Long-slit spectra obtained with the NOAO Phoenix near-infrared spectrometer allow us to probe the molecular kinematics of these nebulae at moderate spatial resolution.
arxiv
VIS‐to‐MIR reflectance and Raman spectroscopy of the CM2 NWA 12184 carbonaceous chondrite
Meteoritics &Planetary Science, Volume 60, Issue 3, Page 570-595, March 2025.Abstract The spectral analysis of CM meteorites can help to constrain the mineralogical composition of their parent body, the C‐type asteroids. The CM2 NWA 12184 was spectrally examined employing seven complementary techniques at different spatial resolutions, including VIS‐to‐MIR reflectance and Raman spectroscopy.
A. Galiano +15 more
wiley +1 more source
Using kinematic properties of pre-planetary nebulae to constrain engine paradigms [PDF]
, 2013 Some combination of binary interactions and accretion plausibly conspire to produce the ubiquitous collimated outflows from planetary nebulae (PN) and their presumed pre-PN (PPN) precursors. But which accretion engines are viable?
E. Blackman, Scott Lucchini
semanticscholar +1 more source
On the Origin of Morphological Structures of Planetary Nebulae
Galaxies, 2018 We suggest that most of the mass in planetary nebulae (PNe) resides in the equatorial region and the spherical envelope and the optically bright lobes of PNe are in fact low-density cavities cleared out by fast outflows and photoionized by UV photons ...
Sun Kwok
doaj +1 more source
Meteoritics &Planetary Science, Volume 60, Issue 3, Page 616-631, March 2025.Abstract Results of microanalysis study of NWA 869 meteorite, an ordinary chondrite, where silicates, Fe‐Ni alloys, and troilite are major constituents, are reported. The presented study of microtextures in metallic and sulfide grains provides information on processes occurring from the asteroid's accretion, through the impacts until cooling.
Paulina Skirak +4 more
wiley +1 more source
In Search of Possible Associations between Planetary Nebulae and Open Clusters [PDF]
, 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. The short lifetimes and low sample size of intermediate-mass planetary nebulae with respect to nearby open clusters conspire to reduce the probability of observing a true association.
arxiv +1 more source
Meteoritics &Planetary Science, Volume 60, Issue 2, Page 190-205, February 2025.Abstract The alignment of non‐spherical “flattened” chondrules into a petrofabric is a common feature of hydrated carbonaceous chondrite meteorites. This texture can form as a result of impacts at peak shock pressures exceeding 10 GPa. However, many carbonaceous chondrites with petrofabrics are unshocked.
Laura E. Jenkins +6 more
wiley +1 more source
A new Planetary Nebula in the outer reaches of the Galaxy [PDF]
, 2011 A proper determination of the abundance gradient in the Milky Way requires the observation of objects at large galactiocentric distances. With this aim, we are exploring the planetary nebula population towards the Galactic Anticentre. In this article, the discovery and physico-chemical study of a new planetary nebula towards the Anticentre direction ...
arxiv +1 more source
Whither or Wither the Sulfur Anomaly in Planetary Nebulae?
The Astrophysical Journal LettersWe present a thorough investigation of the long-standing sulfur anomaly enigma. Our analysis uses chemical abundances from the most extensive data set available for 126 planetary nebulae (PNs) with improved accuracy and reduced uncertainties from a 10° ×
Shuyu Tan, Quentin A. Parker
doaj +1 more source
New Close Binary Central Stars of Planetary Nebulae from Gaia DR3 Epoch Photometry. [PDF]
Res Notes AAS, 2022 Chornay N, Walton NA.
europepmc +1 more source