Search Publications
Up to 1-hour forecasting of radiation hazards from solar energetic ion events with relativistic electrons
Posner, Arik
The sudden and prompt occurrence of solar energetic particle events poses a hazard to manned space activities and interferes with robotic space science missions. This study demonstrates the possibility of short-term forecasting of the appearance and intensity of solar ion events by means of relativistic, near-light speed electrons. A list of the m…
Sun-to-thermosphere simulation of the 28-30 October 2003 storm with the Space Weather Modeling Framework
Roussev, Ilia I.; Sokolov, Igor V.; Gombosi, Tamas I. +4 more
In late October and early November 2003 a series of some of the most powerful solar eruptions ever registered shook the heliosphere. These "Halloween storms" damaged 28 satellites, knocking two out of commission, diverted airplane routes, and caused power failures in Sweden, among other problems. This paper presents a 4-day end-to-end simulation o…
Space weather and deep space communications
Woo, Richard
While Pioneer 11 and Galileo are two deep space missions that experienced radio communication disruptions due to space weather, the success of a mission like Solar Probe, whose goal is to fly by the Sun within a few solar radii of its surface, may depend critically on space weather. It is therefore crucial to thoroughly understand how space weathe…
Statistical study of low-energy heliosphere particle fluxes from 1.4 to 5 AU over a solar cycle
Lanzerotti, L. J.; Armstrong, T. P.; Maclennan, C. G. +4 more
Throughout the entire Ulysses mission, the Heliosphere Instrument for Spectra, Composition, and Anisotropy at Low Energies (HI-SCALE) has collected measurements of low-energy interplanetary ions and electrons. Time series of electron, proton, and ion fluxes have been obtained since 1990. We present statistical studies of high-resolution ion and el…
Properties and geoeffectiveness of halo coronal mass ejections
Gopalswamy, N.; Michalek, G.; Yashiro, S. +1 more
Halo coronal mass ejections (HCMEs) originating from regions close to the center of the Sun are likely to be geoeffective. Assuming that the shape of HCMEs is a cone and that the HCMEs propagate with constant angular widths and velocities, at least in their early phase, we have developed a technique which allowed us to obtain the space speed, widt…
Improved input to the empirical coronal mass ejection (CME) driven shock arrival model from CME cone models
St. Cyr, O. C.; Gopalswamy, N.; Michalek, G. +4 more
We study the Sun-Earth travel time of interplanetary shocks driven by coronal mass ejections (CMEs) using empirical cone models. Three different cone models have been used to obtain the radial speeds of the CMEs, which are then used as input to the empirical shock arrival (ESA) model to obtain the Sun to Earth travel time of the shocks. We compare…
Solar energetic particle flux enhancement as an indicator of halo coronal mass ejection geoeffectiveness
Watermann, J.; Gleisner, H.
Nearly all strong magnetic storms are generated by halo coronal mass ejections (CMEs), but most frontside halo CMEs are not followed by strong storms. Hence additional information is required to discriminate highly geoeffective CMEs from those less geoeffective. There is a tendency for the strongest magnetic storms to be generated by the fastest C…
Structure of magnetic fields in NOAA active regions 0486 and 0501 and in the associated interplanetary ejecta
Yurchyshyn, Vasyl; Abramenko, Valentyna; Hu, Qiang
Spectacular burst of solar activity in October-November 2003, when large solar spots and intense solar flares dominated the solar surface for many consecutive days, caused intense geomagnetic storms. In this paper we analyze solar and interplanetary magnetic fields associated with the storms in October-November 2003. We used space- and ground-base…
The Sun's Fury In Three Dimensions
Simpson, Sarah
The Ulysses spacecraft's unique orbit over the solar poles gives scientists otherwise unattainable insight into the driving forces behind space weather.
Real-time shock arrival predictions during the ``Halloween 2003 epoch''
Dryer, M.; Smith, Z.; Fry, C. D. +3 more
The ``Halloween'' epoch from 19 October to 20 November 2003 was marked by 19 major solar flares that were accompanied by metric type II radio bursts. Several of these flares were followed by major geomagnetic storms. The radio bursts were used in real time because they imply coronal and interplanetary transport. Most of these events were also asso…