Results 11 to 20 of about 2,733 (195)

Comparison of Topographic Roughness of Layered Deposits on Mars

Remote Sensing, 2023
Impact craters with layered ejecta deposits are widespread on Mars. Prevailing views suggest that such ejecta were formed due to the involvement of target water and/or water ice in the impact excavation and/or the post-deposition movement of the impact ...
Wei Cao, Zhiyong Xiao, Fanglu Luo, Yizhen Ma, Rui Xu   +4 more
doaj   +1 more source

The ionization of novae ejecta [PDF]

International Astronomical Union Colloquium, 1990
AbstractNovae ejecta pass through four distinct phases of evolution of the emission-line spectrum, caused by different ionization characteristics of the shell. These include a neutral (I), an auroral (II), a coronal (III), and a nebular (IV) phase. Photoionization from the contracting photosphere of the hot white dwarf is the source of the ionization ...
openaire   +1 more source

Forbush Decrease Characteristics in a Magnetic Cloud

Space Weather, 2020
Based on the new mechanism, the Forbush decrease characteristics are calculated for eight magnetic cloud types. It is shown that the Forbush decrease amplitude does not depend on the magnetic cloud type, while the anisotropy strongly does.
A. S. Petukhova, I. S. Petukhov, S. I. Petukhov   +2 more
doaj   +1 more source

Shocked quartz in distal ejecta from the Ries impact event (Germany) found at ~ 180 km distance, near Bernhardzell, eastern Switzerland

Scientific Reports, 2021
Impact ejecta formation and emplacement is of great importance when it comes to understanding the process of impact cratering and consequences of impact events in general. Here we present a multidisciplinary investigation of a distal impact ejecta layer,
Sanna Holm-Alwmark, Carl Alwmark, Ludovic Ferrière, Matthias M. M. Meier, Sofie Lindström, Gavin G. Kenny, Emma Sheldon, Günter Schweigert, Christoph Spötl, Martin J. Whitehouse, Beda A. Hofmann   +10 more
doaj   +1 more source

Initial 40Ar‐39Ar Ages of the Paleocene‐Eocene Boundary Impact Spherules

Geophysical Research Letters, 2019
We report 40Ar‐39Ar step‐heating ages of Paleocene‐Eocene (P‐E) boundary impact spherules from Atlantic Margin coastal plain and open ocean sites. We test the hypothesis that the P‐E spherules are reworked from an earlier event (e.g., K‐Pg impact at ~66 ...
Morgan F. Schaller, Brent D. Turrin, Megan K. Fung, Miriam E. Katz, Carl C. Swisher   +4 more
doaj   +1 more source

Experimental craters formed by single and multiple buried explosions and implications for volcanic craters with emphasis on maars

Geophysical Research Letters, 2012
Craters at many volcanoes, including most maars, are formed by multiple subsurface explosions. Experiments compared the crater formed by a single large, buried explosion, with craters formed by multiple explosions with the same cumulative energy ...
Greg A. Valentine, James D. L. White, Pierre‐Simon Ross, Jamal Amin, Jacopo Taddeucci, Ingo Sonder, Peter J. Johnson   +6 more
doaj   +1 more source

Infrared Ejecta and Cold Dust in the Young Supernova Remnant N132D

The Astrophysical Journal, 2023
We present Spitzer, Wide-field Infrared Survey Explorer (WISE), and Herschel observations of the young supernova remnant (SNR) N132D in the Large Magellanic Cloud, including 3–40 μ m Spitzer Infrared Spectrograph (IRS) mapping, 12 μ m WISE and 70, 100 ...
Jeonghee Rho, Aravind P. Ravi, Jonathan D. Slavin, Heechan Cha   +3 more
doaj   +1 more source

Atmospheric Interactions of Ejecta on Earth and Mars Including the Effect of Vaporization

The Planetary Science Journal, 2023
Atmospheres play an important role in ejecta deposition after an impact event. Many impact experiments and simulations neglect the effect of atmospheres.
M. A. Carlson, H. J. Melosh, B. C. Johnson   +2 more
doaj   +1 more source

Effects of target temperature on size distribution of ejecta in hypervelocity impact : Toward revision of ISO11227

Mechanical Engineering Journal, 2016
As a preliminary study, the effects of target temperature on ejecta size were examined at an impact velocity of 3.5 km/s with the goal of improving the ISO11227.
Masahiro NISHIDA, Naoto MIYOKAWA, Fumiya KODAMA, Koichi HAYASHI, Pauline FAURE, Koichi NORIMATSU, Yusuke FUJIMURA, Yasuhiro AKAHOSHI   +7 more
doaj   +1 more source

Experimental and Numerical Simulation of Ejecta Size and Velocity of Hypervelocity Impact Rubble-Pile Asteroid

Aerospace
Rubble-pile asteroids may be the type of near-Earth object most likely to threaten Earth in a future collision event. Small-scale impact experiments and numerical simulations for large-scale impacts were conducted to clarify the size ratio of the boulder/
Wenjin Liu, Qingming Zhang, Renrong Long, Jiankang Ren, Juncheng Li, Zizheng Gong, Qiang Wu, Siyuan Ren   +7 more
doaj   +1 more source