formation and evolution
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2022 ◽  
Author(s):  
James Bushong ◽  
Henry Bushong

Conventional theory suggests that black holes are singularities of enormous mass-density: matter compressed beyond imagination due to extreme mass-based gravitational forces and possessing so much mass-based gravity that light itself cannot escape them. As an alternative to convention, this paper builds on the theories of fire-tornado accretion cylinder vortex forces and colossal magnetic pressure spawned within (previously described by the authors in their paper on ~2D planar celestial kinematics), and analyzes them in more detail specifically for black holes and the formation / evolution of galaxies. Several interesting charge-distribution and associated electromagnetic field components will be utilized in the modeling. To demonstrate concept, the proposed forces during formation and evolution will be computationally modeled and translated into visual simulations in 4-D space-time using C# programming in the Unity operating platform.


2022 ◽  
Vol 163 (2) ◽  
pp. 50
Author(s):  
Kyle Franson ◽  
Brendan P. Bowler ◽  
Timothy D. Brandt ◽  
Trent J. Dupuy ◽  
Quang H. Tran ◽  
...  

Abstract Model-independent masses of substellar companions are critical tools to validate models of planet and brown dwarf cooling, test their input physics, and determine the formation and evolution of these objects. In this work, we measure the dynamical mass and orbit of the young substellar companion HD 984 B. We obtained new high-contrast imaging of the HD 984 system with Keck/NIRC2 that expands the baseline of relative astrometry from 3 to 8 yr. We also present new radial velocities of the host star with the Habitable-Zone Planet Finder spectrograph at the Hobby-Eberly Telescope. Furthermore, HD 984 exhibits a significant proper motion difference between Hipparcos and Gaia EDR3. Our joint orbit fit of the relative astrometry, proper motions, and radial velocities yields a dynamical mass of 61 ± 4 M Jup for HD 984 B, placing the companion firmly in the brown dwarf regime. The new fit also reveals a higher eccentricity for the companion (e = 0.76 ± 0.05) compared to previous orbit fits. Given the broad age constraint for HD 984, this mass is consistent with predictions from evolutionary models. HD 984 B’s dynamical mass places it among a small but growing list of giant planet and brown dwarf companions with direct mass measurements.


2022 ◽  
Vol 10 (1) ◽  
pp. 54
Author(s):  
Qian Liu ◽  
Limei Tang ◽  
Ling Chen ◽  
Peng Gao

Seamounts are features generated by hot spots and associated intraplate volcanic activity. The geochemical characteristics of igneous rocks constituting seamounts provide evidence of important details of dynamic processes in the Earth, such as mantle magma source areas, and are key to understanding how mantle plume processes control the formation and evolution of seamounts and their resulting geochemical characteristics. The Pacific Ocean contains a large number of hitherto unstudied seamounts, whose ages and geochemical characteristics remain poorly known. This study presents the geochemical characteristics of six basalt samples from five seamounts in the Western Pacific and the 40Ar/9Ar ages of three samples are determined. The new analysis yielded 40Ar/39Ar ages for seamounts samples MP3D21, MP5D11, and MP5D15A of 95.43 ± 0.33, 62.4 ± 0.26, and 99.03 ± 0.4 Ma, respectively. The geochemical profiles of seamounts samples MP3D04, MP3D21, MP5D11, MP5D15A, MPID201, and MPID202 are consistent with alkaline basalts, as evidence by alkali-rich, silicon-poor compositions along with high titanium concentrations. The primitive mantle normalized rare-earth elements and trace elements spider pattern are similar to those of ocean island basalts. The Ta/Hf and Nb/Zr ratios and La/Zr-Nb/Zr discriminant diagrams indicate that the six seamounts formed from magma that originated in the deep mantle.


Author(s):  
Jie Chen ◽  
Robertus Erdélyi ◽  
Jiajia Liu ◽  
Yuanyong Deng ◽  
Fionnlagh Mackenzie Dover ◽  
...  

An Extreme Ultraviolet (EUV) jet that occurred around 22:30 on July 2, 2012 was observed by the Atmospheric Imaging Assembly (AIA) on-board the Solar Dynamics Observatory (SDO). There were two phases of the jet. In Phase 1, two blobs were observed. In Phase 2, the intensity of the jet was almost coherent initially. One minute later, three blobs were formed at the same time in the jet, and the width of the jet changed after the formation of these blobs. The formation and evolution processes of the blobs in these two phases are analyzed in this paper. The physical parameters of the blobs are determined. The measured width of the blobs is 0.8 − 2.3 Mm, and the apparent velocities of the blobs are from 59 km s−1 to 185 km s−1. The formation mechanism of the blobs is likely to be tear-mode instability.


2022 ◽  
pp. 247-280
Author(s):  
Vernon F. Cormier ◽  
Michael I. Bergman ◽  
Peter L. Olson

2022 ◽  
Vol 206 ◽  
pp. 114237
Author(s):  
Huhu Su ◽  
Xinzhe Zhou ◽  
Shijian Zheng ◽  
Hengqiang Ye ◽  
Zhiqing Yang

2022 ◽  
Vol 08 (01) ◽  
pp. 85-96
Author(s):  
Gabriela Coutinho de Carvalho ◽  
Maria Emília Xavier Guimarães ◽  
Pablo Oliveira Mesquita ◽  
Joaquim Lopes Neto

2022 ◽  
Author(s):  
Tingcong Lin ◽  
Ping Su

In the second half of the 19th century, Shamian was established and developed as a colonial island enclave in the Chinese city of Guangzhou. Simultaneously, literary and cultural imaginations, depictions, and narrations of the place produced a discourse of Shamian as a utopian island: geographically insular and bounded, environmentally beautiful and peaceful, socially exclusive and harmonious, and technologically progressive and advantageous. This paper examines contemporaneous (predominantly English) literary and cultural representations of Shamian as a colonial utopia and their interrelations with the island’s spatial formation and evolution. These texts (primarily written and pictorial descriptive, non-fictional accounts) reflected the spatial reality but also promoted spatial practices that reinforced the physical utopian island. This process exemplifies the theories of performative geographies in island studies and intertextuality in geocriticism, showing how a place’s spatial representations and reality are mutually constructed. Adopting a conceptual model of intertextual performative geographies, this paper investigates the dynamic interplay of these literary and cultural texts with the spatial reality, arguing that literary and cultural representations of Shamian (re)produced the colonial enclave as a utopian island, both conceptually and practically.


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