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Adventures in Space Science
Doschek, George
This memoir is a summary of my early childhood, education, and research career at the Naval Research Laboratory (NRL) in Washington, DC. I describe my early interest in astronomy and how I wound up working in the fields of solar physics and X-ray-UV spectroscopy of high temperature plasmas. I describe some of my home life and other interests, my e…
Reduced Microwave Brightness Temperature in a Sunspot Atmosphere Due to Open Magnetic Fields
White, S. M.; Vrublevskis, A.; Ryabov, B. I.
Motivated by dark coronal lanes in 284 Å extreme-ultraviolet (EUV) observations from the Extreme-ultraviolet Imaging Telescope on board the Solar and Heliospheric Observatory (SOHO/EIT), we construct and optimize an atmosphere model of the active region (AR) 8535 sunspot by adding a cool and dense component in the volume of plasma along open field…
Variations in the Correlations of Acceleration and Force of Slow and Fast CMEs with Solar Activity during Solar Cycles 23 - 24
Du, Zhanle
Studying the behavior of coronal mass ejections (CMEs) is important for both solar physics and space weather. The correlations of smoothed monthly mean daily integrated CME acceleration [a ], mass [M ], and the force [M a ] to drive CMEs with sunspot activity [RI] are analyzed for both slow and fast CMEs and for both Solar Cycles 23 and…
A Simple Technique for Identifying the Propagation Direction of CMEs in 3D Space
Fainshtein, V. G.; Egorov, Y. I.
By now several methods have been proposed enabling to determine the kinematic characteristics of coronal mass ejections (CMEs) in 3D space. Many of these methods are based on using the triangulation technique and stereoscopic observations of the CMEs with two and more spacecraft. As a rule, these methods involve relatively complicated procedures. …
Nature and Variability of the Electron Velocity Distribution Functions and the Nonequilibrium Boltzmann Entropy in the Solar Wind at the First Lagrangian (L1) Point During the Halo CME Event on 25 July 2004
Nampoothiri, Govind G.; Thampi, R. Satheesh; Thampi, Smitha V. +2 more
In this paper, using the measurements at the Sun-Earth first Lagrangian point (L1), the kinetic properties of the electron velocity distribution functions (EVDFs) during the passage of a typical halo coronal mass ejection (CME) has been analyzed. This CME was a front-sided, full halo CME, which erupted on 25 July 2004 (Carrington rotation 2019) fr…
Origin of the Solar Rotation Harmonics Seen in the EUV and UV Irradiance
Giono, G.; Zender, J. J.; Kariyappa, R. +1 more
Long-term periodicities in the solar irradiance are often observed with periods proportional to the solar rotational period of 27 days. These periods are linked either to some internal mechanism in the Sun or said to be higher harmonics of the rotation without further discussion of their origin. In this article, the origin of the peaks in periodic…
Temporal and Spatial Association Between a Solar Flare, CME, and Radio Burst on 19 November 2013
Shanmugaraju, A.; Suresh, K.; Syed Ibrahim, M. +2 more
We present multi-wavelength and multi-instrument observations and analysis of a major X 1.0 class flare, radio burst, halo coronal mass ejection (CME), and loop eruption from the solar active region NOAA 11893 on 19 November 2013 (SOL2013-11-19T10:26). The aim of this work is twofold: The first aim to study the evolution of the loop eruption and t…
Aggregation Characteristics of the Sun's Large-Scale Magnetic Field Associated with a Global Magnetic Anomaly in the Last Extended Solar Cycle
Magara, Tetsuya; An, Junmo; Lee, Hwanhee +1 more
The solar cycle represents the Sun's periodically changing magnetic state, which is potentially subject to global magnetic anomalies emerging on it. What the characteristics are of the Sun's large-scale magnetic field playing roles in these anomalies is a key to clarifying how the Sun deviates from its normal magnetic state. This article reports a…
ICME Evolution in the Inner Heliosphere
Luhmann, J. G.; Jian, L. K.; Gopalswamy, N. +1 more
ICMEs (interplanetary coronal mass ejections), the heliospheric counterparts of what is observed with coronagraphs at the Sun as CMEs, have been the subject of intense interest since their close association with geomagnetic storms was established in the 1980s. These major interplanetary plasma and magnetic field transients, often preceded and acco…
Peculiar Solar Sources and Geospace Disturbances on 20-26 August 2018
Chertok, I. M.; Belov, A. V.; Abunina, M. A. +1 more
On the approach to minimum of Solar Cycle 24, on 26 August 2018, an unexpectedly strong geomagnetic storm (GMS) suddenly occurred. Its Dst index reached −174 nT, that is, the third most intense storm of the cycle. The analysis showed that it was initiated by a two-step long filament eruption, which occurred on 20 August in the central s…