Results 91 to 100 of about 1,721,894 (339)

New knowledge about shock events that affected the L‐chondrite parent body from two heavily shocked L6 meteorite finds

Meteoritics &Planetary Science, EarlyView.
Abstract We report new results from a study of shock‐related features in the L6 ordinary chondrites Northwest Africa (NWA) 4672 and NWA 12841. Our observations confirm the occurrence of eight high‐pressure (HP) minerals in each meteorite, namely, ringwoodite, majorite, akimotoite, wadsleyite, albitic jadeite, lingunite, tuite, and xieite.
I. Baziotis, L. Ferrière, C. Ma, J. Hu, D. Palles, P. D. Asimow   +5 more
wiley   +1 more source

Noble gases and nitrogen in material from asteroid Bennu

Meteoritics &Planetary Science, EarlyView.
Abstract We report the elemental and isotopic abundances of all stable noble gases (helium, neon, argon, krypton, and xenon) in eight particles from asteroid Bennu returned by NASA's OSIRIS‐REx mission. We also report nitrogen abundances and isotopic ratios that were analyzed alongside neon and argon in four additional Bennu particles.
B. Marty, L. Zimmermann, E. Füri, D. V. Bekaert, J. J. Barnes, A. N. Nguyen, H. C. Connolly, D. S. Lauretta   +7 more
wiley   +1 more source

Determining impact angle from the spatial distribution of shock metamorphism: A case study of the Gosses Bluff (Tnorala) impact structure, Australia

Meteoritics &Planetary Science, EarlyView.
Abstract The majority of planetary impacts occur at oblique angles. Impact structures on Earth are commonly eroded or buried, rendering the identification of the direction and angle of impact—using methods such as asymmetries in ejecta distribution, surface topographic expression, central uplift structure, and geophysical anomalies—challenging. In this
Eloise E. Matthews, Auriol S. P. Rae, Thomas Kenkmann, Nicholas E. Timms, Aaron J. Cavosie, Marian B. Holness   +5 more
wiley   +1 more source

Exploring the Components of Cosmogenic UHECR, Neutrino, and Diffuse Gamma Ray from High-Energy Astrophysical Objects

Galaxies
The development of multimessenger astrophysics allows us to probe various background particles from the distant early universe. Up to now, much effort has been made researching the emission and radiation of diverse steady or transient astrophysical ...
Fangsheng Min, Hong Lu, Yiqing Guo
doaj   +1 more source

A dark matter model that reconciles tensions between the cosmic-ray e± excess and the gamma-ray and CMB constraints

Physics Letters B, 2017
The cosmic-ray (CR) e± excess observed by AMS-02 can be explained by dark matter (DM) annihilation. However, the DM explanation requires a large annihilation cross section which is strongly disfavored by other observations, such as the Fermi-LAT gamma ...
Qian-Fei Xiang, Xiao-Jun Bi, Su-Jie Lin, Peng-Fei Yin   +3 more
doaj   +1 more source

Vertical profiling of shock attenuation at the Rochechouart impact structure, France

Meteoritics &Planetary Science, EarlyView.
Abstract Rochechouart, south‐west France, is a complex impact structure. Here, we present the first report of shock barometry of quartz from what are likely parautochthonous basement units at depth, based on samples from the 2017 C.I.R.I.R drilling campaign. The crystallographic orientations of 725 sets of PDFs in 512 quartz grains in samples from four
P. Struzynska, S. Alwmark, C. Alwmark, M. H. Poelchau, P. Lambert   +4 more
wiley   +1 more source

Astrophysical high-energy neutrinos [PDF]

Physics Today, 2018
News from multiple messengers—neutrinos, cosmic rays, and photons—provides clues to the cosmic sources that create some of the most energetic particles observed on Earth.
openaire   +1 more source

Graphite crystallinity and thermal record in Campo del Cielo IAB iron meteorite: A window into impact processing on a chondritic body

Meteoritics &Planetary Science, EarlyView.
Abstract The Campo del Cielo iron meteorite (IAB‐MG) provides a unique window into early solar system processes, particularly the formation and evolution of carbon phases in non‐magmatic iron meteorites. In this study, we conducted a systematic nanostructural investigation of three distinct graphite occurrences—cliftonite (type I), interstitial ...
Xiao Tian Deng, Hong Yi Chen, Yang Li, Jin Yu Zhang, Lan Fang Xie, Si Zhe Zhao, Zhuang Guo, Chen Li, Kai Rui Tai   +8 more
wiley   +1 more source

Small but mighty: Impact hazards from iron Near‐Earth Objects

Meteoritics &Planetary Science, EarlyView.
Abstract Small asteroids can impact Earth unexpectedly, as demonstrated by the Chelyabinsk event in 2013. The warning times are likely to be short, and the first tools for fast hazard predictions have been developed in the last years for encounters with rocky or cometary objects, which quickly fragment in the atmosphere and cause airbursts. However, in
Robert Luther, Natalia Artemieva, Andrea Schmalen, Kai Wünnemann, Detlef Koschny, Richard Moissl   +5 more
wiley   +1 more source

A geophysical investigation of the Roter Kamm impact crater, Namibia

Meteoritics &Planetary Science, EarlyView.
Abstract The Roter Kamm impact crater is located in the southern Namib Desert. The crater has a diameter of 2.5 km and belongs to the category of simple, bowl‐shaped impact craters, with an elevated rim of fractured target rock. The crater's interior is completely buried beneath sediments, preventing extensive surface investigations of the bedrock ...
Hannah Nienhaus, Pritam Yogeshwar, Wiebke Mörbe, Bülent Tezkan, Yajun Liu, Bufelo Lushetile, Martin Melles   +6 more
wiley   +1 more source