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CHIANTI—An Atomic Database for Emission Lines. XVI. Version 10, Further Extensions
Young, P. R.; Del Zanna, G.; Dere, K. P. +1 more
We present version 10 of the CHIANTI package. In this release, we provide updated atomic models for several helium-like ions and for all the ions of the beryllium, carbon, and magnesium isoelectronic sequences that are abundant in astrophysical plasmas. We include rates from large-scale atomic structure and scattering calculations that are in many…
Space weather: the solar perspective: An update to Schwenn (2006)
Temmer, Manuela
The Sun, as an active star, is the driver of energetic phenomena that structure interplanetary space and affect planetary atmospheres. The effects of Space Weather on Earth and the solar system is of increasing importance as human spaceflight is preparing for lunar and Mars missions. This review is focusing on the solar perspective of the Space We…
A Quarter Century of Wind Spacecraft Discoveries
Verscharen, Daniel; Hurley, Kevin; Wicks, Robert T. +11 more
The Wind spacecraft, launched on November 1, 1994, is a critical element in NASA's Heliophysics System Observatory (HSO) - a fleet of spacecraft created to understand the dynamics of the Sun-Earth system. The combination of its longevity (>25 years in service), its diverse complement of instrumentation, and high resolution and accurate measurem…
Earth-affecting solar transients: a review of progresses in solar cycle 24
Dumbović, Mateja; Temmer, Manuela; Dissauer, Karin +16 more
This review article summarizes the advancement in the studies of Earth-affecting solar transients in the last decade that encompasses most of solar cycle 24. It is a part of the effort of the International Study of Earth-affecting Solar Transients (ISEST) project, sponsored by the SCOSTEP/VarSITI program (2014–2018). The Sun-Earth is an integrated…
What sustained multi-disciplinary research can achieve: The space weather modeling framework
Liemohn, Michael W.; van der Holst, Bart; Sokolov, Igor V. +15 more
Magnetohydrodynamics (MHD)-based global space weather models have mostly been developed and maintained at academic institutions. While the "free spirit" approach of academia enables the rapid emergence and testing of new ideas and methods, the lack of long-term stability and support makes this arrangement very challenging. This paper describes a s…
Solar structure and evolution
Christensen-Dalsgaard, Jørgen
The Sun provides a critical benchmark for the general study of stellar structure and evolution. Also, knowledge about the internal properties of the Sun is important for the understanding of solar atmospheric phenomena, including the solar magnetic cycle. Here I provide a brief overview of the theory of stellar structure and evolution, including t…
The first widespread solar energetic particle event observed by Solar Orbiter on 2020 November 29
Kulkarni, S. R.; Lario, D.; Laitinen, T. +66 more
Context. On 2020 November 29, the first widespread solar energetic particle (SEP) event of solar cycle 25 was observed at four widely separated locations in the inner (≲1 AU) heliosphere. Relativistic electrons as well as protons with energies > 50 MeV were observed by Solar Orbiter (SolO), Parker Solar Probe, the Solar Terrestrial Relations Ob…
Understanding the Origins of Problem Geomagnetic Storms Associated with "Stealth" Coronal Mass Ejections
Rouillard, Alexis P.; Pagano, Paolo; Nitta, Nariaki V. +14 more
Geomagnetic storms are an important aspect of space weather and can result in significant impacts on space- and ground-based assets. The majority of strong storms are associated with the passage of interplanetary coronal mass ejections (ICMEs) in the near-Earth environment. In many cases, these ICMEs can be traced back unambiguously to a specific …
Upflows in the Upper Solar Atmosphere
Tian, Hui; Brooks, David H.; Baker, Deborah +2 more
Spectroscopic observations at extreme- and far-ultraviolet wavelengths have revealed systematic upflows in the solar transition region and corona. These upflows are best seen in the network structures of the quiet Sun and coronal holes, boundaries of active regions, and dimming regions associated with coronal mass ejections. They have been intensi…
How much has the Sun influenced Northern Hemisphere temperature trends? An ongoing debate
Henry, Gregory W.; Solheim, Jan-Erik; Scafetta, Nicola +20 more
In order to evaluate how much Total Solar Irradiance (TSI) has influenced Northern Hemisphere surface air temperature trends, it is important to have reliable estimates of both quantities. Sixteen different estimates of the changes in TSI since at least the 19th century were compiled from the literature. Half of these estimates are "low…