Results 41 to 50 of about 107,016 (207)
PHL 932: when is a planetary nebula not a planetary nebula? [PDF]
, 2009 The emission nebula around the subdwarf B (sdB) star PHL 932 is currently classified as a planetary nebula (PN) in the literature. Based on a large body of multi-wavelength data, both new and previously published, we show here that this low-excitation nebula is in fact a small Stromgren sphere (HII region) in the interstellar medium around this star ...
arxiv +1 more source
Meteoritics &Planetary Science, Volume 60, Issue 3, Page 464-483, March 2025.Abstract Xenoliths in carbonaceous chondrites include lithologies that are unrepresented in the meteorite record and so are a rich source of information on asteroid diversity. Cold Bokkeveld is a CM2 regolith breccia that contains both hydrous and anhydrous lithic clasts. Here, we describe a hydrous clast with a fine‐grained rim.
Martin R. Lee +3 more
wiley +1 more source
JWST/MIRI Study of the Enigmatic Mid-infrared Rings in the Planetary Nebula NGC 1514
The Astronomical JournalWhile NGC 1514 is an elliptical, but complex, planetary nebula at optical wavelengths, it was discovered to have a pair of infrared-bright, axisymmetric rings contained within its faint outer shell during the course of the Wide-field Infrared Survey ...
Michael E. Ressler +5 more
doaj +1 more source
Pulsar Wind Nebulae with Thick Toroidal Structure [PDF]
, 2011 We investigate a class of pulsar wind nebulae that show synchrotron emission from a thick toroidal structure. The best studied such object is the small radio and X-ray nebula around the Vela pulsar, which can be interpreted as the result of interaction of a mildly supersonic inward flow with the recent pulsar wind.
arxiv +1 more source
Meteoritics &Planetary Science, Volume 60, Issue 3, Page 506-528, March 2025.Abstract JAXA's Hayabusa2 sample return mission visited the volatile‐rich carbonaceous (C‐type) asteroid (162173) Ryugu with the aim of ground‐truthing remote observations, returning a pristine sample from a C‐type asteroid, and strengthening links between asteroids and the meteorite collection. Here, we have conducted a systematic study of coarse (>10
C. S. Harrison +26 more
wiley +1 more source
Synchrotron heating by a fast radio burst in a self-absorbed synchrotron nebula and its observational signature [PDF]
, 2016 Fast radio bursts (FRBs) are mysterious transient sources. If extragalactic, as suggested by their relative large dispersion measures, their brightness temperatures must be extremely high. Some FRB models (e.g. young pulsar model, magnetar giant flare model, or supra-massive neutron star collapse model) suggest that they may be associated with a ...
arxiv +1 more source
On the Structure and Kinematics of Nebulae around LBVs and LBV Candidates in the LMC [PDF]
Astron.Astrophys.408:205-230,2003, 2003 We present a detailed analysis of the morphology and kinematics of nebulae around LBVs and LBV candidates in the Large Magellanic Cloud. HST images and high-resolution Echelle Spectra were used to determine the size, shape, brightness, and expansion velocities of the LBV nebulae around R127, R143, and S61.
arxiv +1 more source
Meteoritics &Planetary Science, Volume 60, Issue 3, Page 544-569, March 2025.Abstract Refractory inclusions (RIs) in chondrites are widely used as tracers of early solar system formation conditions. In the context of sample‐return missions, a non‐destructive and non‐invasive analytical tool that can rapidly detect and characterize RIs in space samples during their early phase of study is highly needed.
Jean Charlier +4 more
wiley +1 more source
Panchromatic HST/WFC3 Imaging Studies of Young, Rapidly Evolving Planetary Nebulae. II. NGC 7027
The Astrophysical Journal, 2022 The iconic planetary nebula (PN) NGC 7027 is bright, nearby ( D ∼ 1 kpc), highly ionized, intricately structured, and well observed. This nebula is hence an ideal case study for understanding PN shaping and evolution processes.
Paula Moraga Baez +4 more
doaj +1 more source
High Energy emission from Crab Nebula [PDF]
arXiv, 2020 Flaring episodes from Crab Nebula have been observed. A new mechanism of emission is explored. Particles in Crab pulsar are accelerated to multiple Tev energies, by some mechanisms, described in the paper and they are the reason of observed emission. We argue, that after accelerating to high energies, they may maintain the force-free regime - moving ...
arxiv