Results 61 to 70 of about 3,943 (246)

Prebiotic Organic Chemistry of Diketopiperazines

Asian Journal of Organic Chemistry, Volume 15, Issue 4, April 2026.
Diketopiperazines (DKPs) are considered essential in many life forms, but their prebiotic importance has not been fully understood. This review aims to discuss prebiotic organic chemistry for experimentally and computationally simulated reactions involving DKPs. ABSTRACT Even though the significance of amino acids and polypeptides is well recognized in
Jun Ohata
wiley   +1 more source

Ryugu’s observed volatile loss did not arise from impact heating alone

Communications Earth & Environment, 2021
The loss of volatile material from asteroid Ryugu was not caused solely by heating from hypervelocity impacts as previously believed, suggest impact experiments conducted at speeds comparable to those expected in the main asteroid ...
Kosuke Kurosawa, Ryota Moriwaki, Hikaru Yabuta, Ko Ishibashi, Goro Komatsu, Takafumi Matsui   +5 more
doaj   +1 more source

Infrared Lightcurves of Near Earth Objects [PDF]

, 2018
We present lightcurves and derive periods and amplitudes for a subset of 38 near earth objects (NEOs) observed at 4.5 microns with the IRAC camera on the the Spitzer Space Telescope, many of them having no previously reported rotation periods.
Chesley, Steven, Emery, Joshua P., Fazio, Giovanni G., Gustafsson, Annika, Harris, Alan, Hora, Joseph L., McNeill, Andrew, Mommert, Michael, Mueller, Michael, Siraj, Amir, Smith, Howard A., Trilling, David E.   +11 more
core   +5 more sources

Small‐scale elemental abundance variations in Ryugu particles from touchdown 1

Meteoritics &Planetary Science, Volume 61, Issue 4, Page 580-599, April 2026.
Abstract Ryugu materials closely resemble CI chondrites' mineralogical, chemical, and isotopic compositions; yet minor but resolvable differences in certain elemental abundances are evident. In this study, the bulk chemical compositions of eight individual Ryugu particles (1.5–4.3 mg) from the first touchdown site (TD1) were determined using triple ...
Karina López García, Tetsuya Yokoyama, Ikshu Gautam, Makiko K. Haba, Tsuyoshi Iizuka, Nao Nakanishi, Ryota Fukai   +6 more
wiley   +1 more source

Shifting communities after­­ typhoon damage on an upper mesophotic reef in Okinawa, Japan [PDF]

PeerJ, 2017
Very few studies have been conducted on the long-term effects of typhoon damage on mesophotic coral reefs. This study investigates the long-term community dynamics of damage from Typhoon 17 (Jelawat) in 2012 on the coral community of the upper mesophotic
Kristine N. White, David K. Weinstein, Taku Ohara, Vianney Denis, Javier Montenegro, James D. Reimer   +5 more
doaj   +2 more sources

Microstructural and chemical features of impact melts on Ryugu particle surfaces: Records of interplanetary dust hit on asteroid Ryugu. [PDF]

Sci Adv
The Hayabusa2 spacecraft delivered samples of the carbonaceous asteroid Ryugu to Earth. Some of the sample particles show evidence of micrometeoroid impacts, which occurred on the asteroid surface.
Matsumoto M, Matsuno J, Tsuchiyama A, Nakamura T, Enokido Y, Kikuiri M, Nakato A, Yasutake M, Uesugi K, Takeuchi A, Enju S, Okumura S, Mitsukawa I, Sun M, Miyake A, Haruta M, Igami Y, Yurimoto H, Noguchi T, Okazaki R, Yabuta H, Naraoka H, Sakamoto K, Tachibana S, Zolensky M, Yada T, Nishimura M, Miyazaki A, Yogata K, Abe M, Okada T, Usui T, Yoshikawa M, Saiki T, Tanaka S, Terui F, Nakazawa S, Watanabe SI, Tsuda Y.   +38 more
europepmc   +2 more sources

Initial study of regolith exposure ages and burial conditions on Ryugu: Cosmogenic nuclides score in two touchdowns

Meteoritics &Planetary Science, Volume 61, Issue 4, Page 565-579, April 2026.
Abstract Surface processes on the asteroid Ryugu have been investigated using cosmic‐ray‐produced radionuclides, 10Be, 26Al, and 36Cl, and stable noble gases, on eight samples returned by the Hayabusa2 spacecraft. The 10Be and 26Al along with 21Ne measurements indicate that the two Chamber A samples A0105 collected during the first touchdown (TD) were ...
Kunihiko Nishiizumi, Keisuke Nagao, Marc W. Caffee, Ryuji Okazaki, Jozef Masarik, Hisayoshi Yurimoto, Tomoki Nakamura, Takaaki Noguchi, Hiroshi Naraoka, Hikaru Yabuta, Kanako Sakamoto, Kasumi Yogata, Toru Yada, Shogo Tachibana, Sei‐ichiro Watanabe, Yuichi Tsuda, Masanao Abe, Kazuya Kumagai, Akiko Miyazaki, Aiko Nakato, Satoru Nakazawa, Masahiro Nishimura, Tatsuaki Okada, Takanao Saiki, Hirotaka Sawada, Satoshi Tanaka, Tomohiro Usui, Koji Wada, Hajime Yano, Makoto Yoshikawa, Hayabusa2 Initial Analysis Volatile Team   +30 more
wiley   +1 more source

Non‐innocent solvents in meteorite extractions: Evidence for artifact formation

Meteoritics &Planetary Science, Volume 61, Issue 4, Page 706-719, April 2026.
Abstract Solvent extraction is a cornerstone of meteoritic organic and inorganic chemistry, yet the assumption that common solvents act as chemically inert media is becoming increasingly untenable. This study reports that low‐molecular‐weight alcohols, particularly methanol and ethanol, are “non‐innocent” solvents when used to extract soluble sulfur ...
N. Randazzo, R. W. Hilts, R. M. Whittal, B. Reiz, V. Olan‐Rubio, C. D. K. Herd, I. H. Krouse   +6 more
wiley   +1 more source

Visualization of nanoscale magnetic domain states in the asteroid Ryugu

Scientific Reports, 2023
In the samples collected from the asteroid Ryugu, magnetite displays natural remanent magnetization due to nebular magnetic field, whereas contemporaneously grown iron sulfide does not display stable remanent magnetization.
Yuki Kimura, Takeharu Kato, Toshiaki Tanigaki, Tetsuya Akashi, Hiroto Kasai, Satoshi Anada, Ryuji Yoshida, Kazuo Yamamoto, Tomoki Nakamura, Masahiko Sato, Kana Amano, Mizuha Kikuiri, Tomoyo Morita, Eiichi Kagawa, Toru Yada, Masahiro Nishimura, Aiko Nakato, Akiko Miyazaki, Kasumi Yogata, Masanao Abe, Tatsuaki Okada, Tomohiro Usui, Makoto Yoshikawa, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Satoru Nakazawa, Hisayoshi Yurimoto, Takaaki Noguchi, Ryuji Okazaki, Hikaru Yabuta, Hiroshi Naraoka, Kanako Sakamoto, Sei-ichiro Watanabe, Yuichi Tsuda, Shogo Tachibana   +35 more
doaj   +1 more source

The MASCOT Magnetometer [PDF]

, 2015
The Mobile Asteroid Scout (MASCOT) is a small lander on board the Hayabusa2 mission of the Japan Aerospace Exploration Agency to the asteroid 162173 Ryugu. Among the instruments on MASCOT is a fluxgate magnetometer, the MASCOT Magnetometer (MasMag).
Auster, Hans-Ulrich, Blum, Jürgen, Fornaçon, Karl-Heinz, Fujimoto, Masaki, Gebauer, Kathrin, Glassmeier, Karl-Heinz, Güttler, Carsten, Herčík, David, Hillenmaier, Olaf, Hördt, Andreas, Liebert, Evelyn, Matsuoka, Ayako, Nomura, Reiko, Richter, Ingo, Stoll, Bernd, Weiss, Benjamin P   +15 more
core   +1 more source