Results 81 to 90 of about 22,425 (264)

Metallic messengers from the cosmos: Rare (Al,Cu)‐bearing meteorites from the Project Stardust collection

Meteoritics &Planetary Science, Volume 60, Issue 7, Page 1609-1620, July 2025.
Abstract We report the discovery of (Al,Cu)‐bearing metallic alloys in two micrometeorites found in the Project Stardust collection gathered from urban rooftop environments in Norway. Most of the alloys are the same as those found in the Khatyrka meteorite and other micrometeorites, though one has a composition that has not been reported previously ...
Luca Bindi, Jon Larsen, Jan B. Kihle, Guangming Cheng, Jinping Hu, Nan Yao, Chi Ma, Yunbin Guan, Paul D. Asimow, Paul J. Steinhardt   +9 more
wiley   +1 more source

Effect of Time-varying X-Ray Emission from Stellar Flares on the Ionization of Protoplanetary Disks

The Astrophysical Journal
X-rays have significant impacts on cold, weakly ionized protoplanetary disks by increasing the ionization rate and driving chemical reactions. Stellar flares are explosions that emit intense X-rays and are the unique source of hard X-rays with an energy ...
Haruka Washinoue, Shinsuke Takasao, Kenji Furuya   +2 more
doaj   +1 more source

A Method to Constrain the Size of the Protosolar Nebula

, 2012
Observations indicate that the gaseous circumstellar disks around young stars vary significantly in size, ranging from tens to thousands of AU. Models of planet formation depend critically upon the properties of these primordial disks, yet in general it ...
Buie, M. W., Kretke, K. A., Levison, H. F., Morbidelli, A.   +3 more
core   +3 more sources

An overview of the petrography and petrology of particles from aggregate sample from asteroid Bennu

Meteoritics &Planetary Science, Volume 60, Issue 5, Page 979-996, May 2025.
Abstract The OSIRIS‐REx mission returned a sample of regolith from the carbonaceous asteroid Bennu in September 2023. We present preliminary in situ investigations of the petrology and petrography of selected particles ranging in size from 0.5 to 3 mm.
Harold C. Connolly Jr, Dante S. Lauretta, Timothy J. McCoy, Sara S. Russell, Pierre Haenecour, Anjani Polit, Jessica J. Barnes, Thomas J. Zega, Hisayoshi Yurimoto, Noriyuki Kawasaki, Kevin Righter, Guy Libourel, Marc Portail, Vincent Guigoz, Ashley J. King, Lindsay P. Keller, Kathy Thomas‐Keprta, Loan Le, Valarie Tu, Scott A. Eckley, Catherine M. Corrigan, Timothy Gooding, Timothy Rose, Rob Wardell, Soumya Ray, Victoria E. Hamilton, Nicole G. Lunning, Christopher J. Snead, Francis M. McCubbin, Michelle S. Thompson, Rhian H. Jones, Kenneth Domanik, Dolores Hill, Lucas Smith, Iunn J. Ong, Tobias Salge, Natasha Almeida, Catherine Harrison, Helena Bates, Paul Schofield, Ian A. Franchi, Brian H. May, Claudia Manzoni, Andrew J. Ryan, Ronald‐Louis Ballouz, Robert J. Macke, Jason P. Dworkin, Charles C. Lorentson, Kimberly Tait, Erica R. Jawin, Hannah H. Kaplan, Daniella N. DellaGuistina, Kevin J. Walsh, Michael C. Moreau, Heather L. Enos, C. W. V. Wolner, Heather L. Roper, Shogo Tachibana   +57 more
wiley   +1 more source

Hydration and dehydration of CM chondrites revealed by X‐ray diffraction combined with textural observations and compositional data

Meteoritics &Planetary Science, Volume 60, Issue 5, Page 1194-1215, May 2025.
Abstract The in‐plane rotation method is used to obtain X‐ray random diffraction (XRD) patterns of polished thin sections of 10 CM chondrites. The samples include five intermediately altered CM chondrites with subtypes 2.6–2.3, two heavily altered CM chondrites with subtype 2.0 and three with secondary heating after hydration (Y 980036, Y 980051, and ...
Naoya Imae, Makoto Kimura, Akira Yamaguchi   +2 more
wiley   +1 more source

Using X‐ray computed microtomography (μCT) to determine subsample‐specific cosmogenic noble gas production rates of E (enstatite) chondrites

Meteoritics &Planetary Science, Volume 60, Issue 3, Page 442-463, March 2025.
Abstract Cosmic ray exposure (CRE) ages provide information about the parent bodies and source regions of meteorite classes. Cosmogenic noble gases are often used to quantify exposure time scales ranging from tens of ka to hundreds of Ma. The production rate of cosmogenic noble gases is primarily controlled by a meteorite's chemical composition ...
M. Mijjum, B. J. Andrews, T. J. McCoy, C. M. Corrigan, M. W. Caffee, M. M. Tremblay   +5 more
wiley   +1 more source

JWST Imaging of Edge-on Protoplanetary Disks. I. Fully Vertically Mixed 10 μm Grains in the Outer Regions of a 1000 au Disk

The Astronomical Journal
Scattered light imaging of protoplanetary disks provides key insights on the geometry and dust properties in the disk surface. Here, we present James Webb Space Telescope (JWST) 2–21 μ m images of a 1000 au radius edge-on protoplanetary disk surrounding ...
Gaspard Duchêne, François Ménard, Karl R. Stapelfeldt, Marion Villenave, Schuyler G. Wolff, Marshall D. Perrin, Christophe Pinte, Ryo Tazaki, Deborah L. Padgett   +8 more
doaj   +1 more source

Formation and evolution of the protoplanetary disk [PDF]

A disk formation model during collapse of the protosolar nebula, yielding a low-mass protoplanetary disk is presented. The following subject areas are covered: (1) circumstellar disks; (2) conditions for the formation of stars with disks; (3) early ...
Makalkin, A. B., Ruzmaikina, Tamara V.
core   +1 more source

A Deep Search for Complex Organic Molecules toward the Protoplanetary Disk of V883 Ori

The Astronomical Journal
Complex organic molecules (COMs) in the form of prebiotic molecules are potential building blocks of life. Using Atacama Large Millimeter/submillimeter Array Band 7 observations in spectral scanning mode, we carried out a deep search for COMs within the ...
Abubakar M. A. Fadul, Kamber R. Schwarz, Merel L. R. van ’T Hoff, Jane Huang, Jennifer B. Bergner, Tushar Suhasaria, Jenny K. Calahan   +6 more
doaj   +1 more source

Physical Processes in Protoplanetary Disks [PDF]

, 2019
This review introduces physical processes in protoplanetary disks relevant to accretion and the initial stages of planet formation. After a brief overview of the observational context, I introduce the elementary theory of disk structure and evolution, review the gas-phase physics of angular momentum transport through turbulence and disk winds, and ...
openaire   +2 more sources