Results 31 to 40 of about 64,440 (194)

Possible Ribose Synthesis in Carbonaceous Planetesimals

Life, 2022
The origin of life might be sparked by the polymerization of the first RNA molecules in Darwinian ponds during wet-dry cycles. The key life-building block ribose was found in carbonaceous chondrites.
Klaus Paschek, Kai Kohler, Ben K. D. Pearce, Kevin Lange, Thomas K. Henning, Oliver Trapp, Ralph E. Pudritz, Dmitry A. Semenov   +7 more
doaj   +1 more source

The Magnesium Isotope Composition of Samples Returned from Asteroid Ryugu

The Astrophysical Journal Letters, 2023
The nucleosynthetic isotope composition of planetary materials provides a record of the heterogeneous distribution of stardust within the early solar system.
Martin Bizzarro, Martin Schiller, Tetsuya Yokoyama, Yoshinari Abe, Jérôme Aléon, Conel M. O’D. Alexander, Sachiko Amari, Yuri Amelin, Ken-ichi Bajo, Audrey Bouvier, Richard W. Carlson, Marc Chaussidon, Byeon-Gak Choi, Nicolas Dauphas, Andrew M. Davis, Tommaso Di Rocco, Wataru Fujiya, Ryota Fukai, Ikshu Gautam, Makiko K. Haba, Yuki Hibiya, Hiroshi Hidaka, Hisashi Homma, Peter Hoppe, Gary R. Huss, Kiyohiro Ichida, Tsuyoshi Iizuka, Trevor R. Ireland, Akira Ishikawa, Shoichi Itoh, Noriyuki Kawasaki, Noriko T. Kita, Kouki Kitajima, Thorsten Kleine, Shintaro Komatani, Alexander N. Krot, Ming-Chang Liu, Yuki Masuda, Mayu Morita, Fréderic Moynier, Kazuko Motomura, Izumi Nakai, Kazuhide Nagashima, David Nesvorný, Ann Nguyen, Larry Nittler, Morihiko Onose, Andreas Pack, Changkun Park, Laurette Piani, Liping Qin, Sara S. Russell, Naoya Sakamoto, Maria Schönbächler, Lauren Tafla, Haolan Tang, Kentaro Terada, Yasuko Terada, Tomohiro Usui, Sohei Wada, Meenakshi Wadhwa, Richard J. Walker, Katsuyuki Yamashita, Qing-Zhu Yin, Shigekazu Yoneda, Edward D. Young, Hiroharu Yui, Ai-Cheng Zhang, Tomoki Nakamura, Hiroshi Naraoka, Takaaki Noguchi, Ryuji Okazaki, Kanako Sakamoto, Hikaru Yabuta, Masanao Abe, Akiko Miyazaki, Aiko Nakato, Masahiro Nishimura, Tatsuaki Okada, Toru Yada, Kasumi Yogata, Satoru Nakazawa, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Yuichi Tsuda, Sei-ichiro Watanabe, Makoto Yoshikawa, Shogo Tachibana, Hisayoshi Yurimoto   +89 more
doaj   +1 more source

Clasts in the CM2 carbonaceous chondrite Lonewolf Nunataks 94101: evidence for aqueous alteration prior to complex mixing [PDF]

, 2013
Clasts in the CM2 carbonaceous chondrite Lonewolf Nunataks (LON) 94101 have been characterized using scanning and transmission electron microscopy and electron microprobe analysis to determine their degrees of aqueous alteration, and the timing of ...
Bischoff A., Bischoff A., Brearley A. J, Huss G. R., Zolensky M. E.   +4 more
core   +1 more source

New carbonaceous chondrite Northwest Africa 11781 (CM2)

Литосфера, 2019
Research subject. The article presents the results of a study of a new meteorite Northwest Africa 11781.Material and methods. The material for the study was a fragment of a meteorite weighing 15.56 g, from which 4 transparent polished sections with a ...
K. A. Dugushkina, S. V. Berzin
doaj   +1 more source

Fluid evolution in CM carbonaceous chondrites tracked through the oxygen isotopic compositions of carbonates [PDF]

, 2017
The oxygen isotopic compositions of calcite grains in four CM carbonaceous chondrites have been determined by NanoSIMS, and results reveal that aqueous solutions evolved in a similar manner between parent body regions with different intensities of ...
Alexander, Alexander, Barber, Benedix, Bland, Bonal, Bunch, Burbine, Clark, Clayton, Clayton, de Leuw, DuFresne, Emery, Fujiya, Fujiya, Guo, Hewins, Horita, Howard, I.A. Franchi, Jenniskens, Johnson, Kasuga, Lauretta, Lee, Lee, Lee, Lee, Lee, Lee, Lindgren, Lindgren, M.R. Lee, Marrocchi, McSween, McSween, N.A. Starkey, P. Lindgren, Palguta, Rubin, Rubin, Starkey, Tomeoka, Tyra, Tyra, Tyra, Velbel, Young, Young   +49 more
core   +2 more sources

Meteorites and the RNA World: Synthesis of Nucleobases in Carbonaceous Planetesimals and the Role of Initial Volatile Content

The Astrophysical Journal, 2023
Prebiotic molecules, fundamental building blocks for the origin of life, have been found in carbonaceous chondrites. The exogenous delivery of these organic molecules onto the Hadean Earth could have sparked the polymerization of the first RNA molecules ...
Klaus Paschek, Dmitry A. Semenov, Ben K. D. Pearce, Kevin Lange, Thomas K. Henning, Ralph E. Pudritz   +5 more
doaj   +1 more source

Presolar grains in primitive ungrouped carbonaceous chondrite Northwest Africa 5958 [PDF]

Meteoritics and Planetary Science, 2019
We report a correlated NanoSIMS‐transmission electron microscopy study of the ungrouped carbonaceous chondrite Northwest Africa (NWA) 5958. We identified 10 presolar SiC grains, 2 likely presolar graphite grains, and 20 presolar silicate and/or oxide ...
L. Nittler, R. Stroud, C. Alexander, K. Howell   +3 more
semanticscholar   +1 more source

Distant Formation and Differentiation of Outer Main Belt Asteroids and Carbonaceous Chondrite Parent Bodies

AGU Advances, 2022
Volatile compositions of asteroids provide information on the Solar System history and the origins of Earth's volatiles. Visible to near‐infrared observations at wavelengths of 4) and low temperatures (10 au) and could be transported to their current ...
H. Kurokawa, T. Shibuya, Y. Sekine, B. L. Ehlmann, F. Usui, S. Kikuchi, M. Yoda   +6 more
doaj   +1 more source

The Origin and Physico-Chemical Properties of Some Unusual Earth Rock Fragments

Applied Sciences, 2022
In this paper, several researches were undertaken related to a violent phenomenon, characterized by a sonic boom, felt on an area of at least 500 km2, shortly followed by the fall of rock fragments that were then recovered from the ground.
Alexandru Cocean, Cristina Postolachi, Georgiana Cocean, Georgiana Bulai, Bogdanel Silvestru Munteanu, Nicanor Cimpoesu, Iuliana Cocean, Silviu Gurlui   +7 more
doaj   +1 more source

Trace element geochemistry of ordinary chondrite chondrules: the type I/type II chondrule dichotomy [PDF]

, 2015
We report trace element concentrations of silicate phases in chondrules from LL3 ordinary chondrites Bishunpur and Semarkona. Results are similar to previously reported data for carbonaceous chondrites, with rare earth element (REE) concentrations ...
Alard, Olivier, Gounelle, Matthieu, Jacquet, Emmanuel   +2 more
core   +2 more sources