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Not So Fast, Not So Furious: Just Magnetic
Villaver, Eva; Landstreet, John D.; Bagnulo, Stefano
WD 0810-353 is a white dwarf within the 20 pc volume around the Sun. Using Gaia astrometric distance and proper motions, and a radial velocity derived from Gaia spectroscopy, it has been predicted that this star will pass within 1 pc of the solar system in about 30 kyr. However, WD 0810-353 has been also shown to host a magnetic field with a stren…
Rapidly Evolving Transients in Archival ZTF Public Alerts
Filippenko, Alexei V.; Yang, Yi; Li, Wenxiong +8 more
We search the archival Zwicky Transient Facility public survey for rapidly evolving transient (RET) candidates based on well-defined criteria between 2018 May and 2021 December. The search yielded 19 bona fide RET candidates, corresponding to a discovery rate of ~5.2 events per year. Even with a Galactic latitude cut of 20°, eight of the 19 events…
Confinedness of an X3.1-class Solar Flare Occurred in NOAA 12192: Analysis from Multi-instrument Observations
Guglielmino, S. L.; Zuccarello, F.; Ferrente, F. +1 more
The nonassociation of coronal mass ejections with high energetic flares is sparse. For this reason, the magnetic conditions required for the confinedness of major flares is a topic of active research. Using multi-instrument observations, we investigated the evolution and effects of confinedness in an X3.1 flare, which occurred in active region (AR…
The Hydrostatic Mass of A478: Discrepant Results from Chandra, NuSTAR, and XMM-Newton
Wik, Daniel R.; Schellenberger, Gerrit; Wang, Qian H. S. +3 more
Galaxy clusters are the most recently formed and most massive, gravitationally bound structures in the Universe. The number of galaxy clusters formed is highly dependent on cosmological parameters, such as the dark matter density, σ 8, and Ω m . The number density is a function of the cluster mass, which can be estimated from…
Modeling the Radiation Environment of Energetic Particles at Mars Orbit and a First Validation against TGO Measurements
Guo, Jingnan; Liu, Weihao; Semkova, Jordanka +1 more
Sending astronauts to Mars will be a milestone of future deep space exploration activities. However, energetic particle radiation in deep space and in the Mars environment is a major risk to the health of future human explorers. The nominal Martian surface radiation field contains primary Galactic Cosmic Ray (GCR) particles and secondary particles…
The SPHEREx Target List of Ice Sources (SPLICES)
Kang, Miju; Lee, Jeong-Eun; Lee, Ho-Gyu +16 more
One of the primary objectives of the SPHEREx mission is to understand the origin of molecules such as H2O, CO2, and other volatile compounds at the early stages of planetary system formation. Because the vast majority of these compounds-typically exceeding 95%-exist in the solid phase rather than the gaseous phase in the syst…
Influence of an Upstream Dynamic Pressure Pulse on Venus-Solar Wind Interaction by Multispecies Magnetohydrodynamic Simulation
Cao, Jinbin; Li, Yun; Xiong, Ruijing +4 more
As an unmagnetized planet, Venus does not have a global dipole magnetic field like Earth. The solar wind interacts directly with the Venusian ionosphere. In this paper, the interaction between solar wind and the Venusian upper atmosphere is investigated by conducting a three-dimensional multispecies magnetohydrodynamic (MHD) model, in which the Ve…
The Chemodynamical Nature of the Triangulum-Andromeda Overdensity
Placco, Vinicius M.; Limberg, Guilherme; Rossi, Silvia +7 more
We present a chemodynamical study of the Triangulum-Andromeda overdensity (TriAnd) employing a sample of 31 candidate stars observed with the GRACES high-resolution (R = 40,000) spectrograph at the Gemini North (8.1 m) telescope. TriAnd is a stellar substructure found toward the outer disk of the Milky Way, located at R GC ~ 18 kpc from…
Are Nonthermal Velocities in Active Region Coronal Loops Anisotropic?
Hahn, Michael; Asgari-Targhi, Mahboubeh; Savin, Daniel Wolf
We have measured line widths in active region coronal loops in order to determine whether the nonthermal broadening is anisotropic with respect to the magnetic field direction. These nonthermal velocities are caused by unresolved fluid motions. Our analysis method combines spectroscopic data and a magnetic field extrapolation. We analyzed spectra …
Solar Filament Eruptions in H α Doppler Velocity
Pevtsov, A. A.; Tlatov, A. G.; Berezin, I. A.
We use observations taken with a novel solar telescope spectroheliograph to investigate the association between the early filament rise and coronal mass ejections (CMEs). The instrument allows the H α full line profile to be registered in each pixel of the solar disk with a time cadence of about 1 minute. We analyze observations of thr…