Results 41 to 50 of about 6,433 (179)

Modeling enstatite chondrites: Reduced rocks with a pinch of oxidized material (affected by varying H2O(g)) derived from planetesimals shocked during the epoch of giant–planet migration

Meteoritics &Planetary Science, Volume 61, Issue 1, Page 122-139, January 2026.
Abstract The O‐, N‐, Mo‐, Ru‐, Os‐, Cr‐, Ti‐, Ni‐, Fe‐, Nd‐, Ca‐, Zn‐, Sr‐, and Mg‐isotopic compositions of enstatite chondrites are essentially identical to those of the Earth and Moon. These correspondences suggest enstatite chondrites formed at ≈1 AU as the only known chondrite groups that accreted in the vicinity of a major planet. Bulk Earth has a
Alan E. Rubin
wiley   +1 more source

Spectroscopic Survey of Faint Planetary-nebula Nuclei. IV. The A35-type Central Star of Pa 27

The Astrophysical Journal
We present optical spectroscopy of the 12th-magnitude central star of the planetary nebula (PN) Patchick 27 (Pa 27), obtained during a survey of faint PN nuclei (PNNs) with the Low-Resolution Spectrograph of the Hobby–Eberly Telescope.
Howard E. Bond, Gregory R. Zeimann
doaj   +1 more source

Planetary nebulae in M32 and the bulge of M31: Line intensities and oxygen abundances [PDF]

, 1998
We present spectroscopy of planetary nebulae in M32 and in the bulge of M31 that we obtained with the MOS spectrograph at the Canada-France-Hawaii Telescope. Our sample includes 30 planetary nebulae in M31 and 9 planetary nebulae in M32. We also observed
McCall, Marshall L., Richer, Michael G., Stasinska, Grazyna   +2 more
core   +2 more sources

Morphologies of Planetary Nebulae with Close-Binary Nuclei [PDF]

Symposium - International Astronomical Union, 1989
We will present photographic and CCD images of planetary nebulae that are known, on the basis of photometric observations of the central stars, to possess close-binary nuclei. All of the orbital periods range from 2.7 to 16 hours, except for the 16-day binary nucleus of NGC 2346.
Howard E. Bond, Mario Livio, Michael Meakes   +2 more
openaire   +1 more source

Physiology of nitrogen: A life or death matter

Experimental Physiology, Volume 111, Issue 1, Page 270-282, 1 January 2026.
Abstract With each breath, four out of every five molecules we inspire are nitrogen (N2), since this gas constitutes ∼80% of the atmospheric air that surrounds us. Despite its abundance and unlike molecular oxygen, N2 has traditionally held less appeal among physiologists given its lack of reactivity and corresponding inability to support combustion or
Damian M. Bailey, Vaughan G. Macefield, David C. Poole   +2 more
wiley   +1 more source

Evidence for binarity in the bipolar planetary nebulae A79, He2-428 and M1-91 [PDF]

, 2001
We present low and high resolution long-slit spectra of three bipolar planetary nebulae (PNe) with bright central cores: A79, He2-428 and M1-91. He2-428 and M1-91 have high density (from 10^3.3 to 10^6.5 cm^-3) unresolved nebular cores that indicate that
A. Mampaso, Balick, Barker, Bautista, Benjamin, Blöcker, Bobrowsky, Calvet, Cardelli, Chevalier, Cieslinski, Corradi, Corradi, Corradi, Costa, Doyle, Drake, Esteban, Feibelman, Froese Fischer, García-Lario, Garstang, Goodrich, Guerrero, Hamann, Howard, Hyung, Icke, Jacoby, Jenniskens, Kingsburgh, M. Rodríguez, Maciel, Magnan, McKenna, Morris, Osterbrock, Perinotto, Persson, Persson, Persson, Pottasch, Quinet, R. L. M. Corradi, Rauch, Rodríguez, Soker, Soker, Solf, Storey, Swings, van Winckel, Zhang, Zhang, Zhang, Zuckerman   +55 more
core   +2 more sources

Evolution of Terrestrial Planetary Bodies and Implications for Habitability

Reviews of Geophysics, Volume 63, Issue 4, December 2025.
Abstract The terrestrial planetary bodies of our solar system—Mercury, Venus, Earth, and Mars—share a common origin through nebular accretion and early magma ocean differentiation, yet they diverged significantly in geological evolution, tectonic regimes, and habitability.
Peter A. Cawood, Eva E. Stüeken, Priyadarshi Chowdhury, Chris J. Hawkesworth, Jacob A. Mulder   +4 more
wiley   +1 more source

Birth and early evolution of a planetary nebula [PDF]

, 1998
The final expulsion of gas by a star as it forms a planetary nebula --- the ionized shell of gas often observed surrounding a young white dwarf --- is one of the most poorly understood stages of stellar evolution.
A Frank, A Frank, A Riera, G Mellema, IG Kolesnik, J Cantó, J Maddox, JR Kozok, JR Kozok, Kailash C. Sahu, KC Sahu, KG Henize, KG Henize, KJ Borkowski, KU Ratnatunga, LR Youngelson, M Bobrowsky, M Bobrowsky, M Livio, M Livio, M Morris, M Parthasarathy, M Parthasarathy, M. Parthasarathy, Matthew Bobrowsky, N Soker, Pedro García-Lario, S Casertano, S Kwok, SR Pottasch, T Blöcker, T Blöcker, V Icke, WA Feibelman   +33 more
core   +3 more sources

KINEMATICAL PROPERTIES OF PLANETARY NEBULAE WITH WR-TYPE NUCLEI

Publications of The Korean Astronomical Society, 2015
We have carried out integral field unit (IFU) spectroscopy of H$ $, [N II] and [O III] emission lines for a sample of Galactic planetary nebulae (PNe) with Wolf-Rayet (WR) stars and weak emission-line stars (wels). Comparing their spatially-resolved kinematic observations with morpho-kinematic models allowed us to disentangle their three-dimensional ...
Parker, QA, Steffen, W, Danehkar, A
openaire   +4 more sources

Löpönvaara: A new phosphorus‐rich iron meteorite from Finland

Meteoritics &Planetary Science, Volume 60, Issue 10, Page 2442-2457, October 2025.
Abstract Löpönvaara is a rare new phosphorus‐rich iron meteorite find from Löpönvaara, Finland. The ~164 g meteorite was discovered in 2017 from the same area as the ungrouped Lieksa pallasite. Löpönvaara was classified as an ungrouped iron meteorite due to its unusually high concentration of P (>4 wt%), coupled with a moderate concentration of Ni (~11 
Laura Kotomaa, Markku Väisänen, Jussi S. Heinonen, Ermei Mäkilä, Hugh O'Brien, Arto Peltola   +5 more
wiley   +1 more source