Conveners
Space Science: Helio and Plasma Physics
- Rendani nndanganeni (South African Nation Space Agency)
Space Science: Ionosphere
- KATLEGO MOLOTO (NORTH WEST UNIVERSITY)
Space Science: Radiation and Cosmic Rays
- Du Toit Strauss (Centre for Space Research, North-West University)
Space Science
- There are no conveners in this block
Space Science
- There are no conveners in this block
Arbitrary amplitude nonlinear ion-acoustic waves are investigated in a three-component magnetised plasma consisting of inertial adiabatic ions and two-temperature electrons. The existence of nonlinear solitary wave structures is determined using the Sagdeev pseudopotential formalism, under the assumption of quasineutrality. The direction of wave propagation is oblique to the ambient magnetic...
The Sagdeev pseudopotential formalism is used to investigate beam effects associated with drifting ions on the acoustic modes in a plasma which is composed of two warm (adiabatic) ion components and one or two-electron components (of different temperatures). One or both ion species are treated as drifting (beam) component(s). The primary objective of the study is to investigate the effect of...
The Vacuum Arc Thruster (VAT) is a simple electric propulsion system utilising pulsed arc discharges. Due to its low mass and power requirements, it is a candidate for small satellite space science missions. However, its thrust to power ratio, fuel efficiency and total impulse are much lower than larger, more traditional systems such as Hall effect and gridded ion thrusters. In this work the...
The implementation of a pulsed magnetic field to the plasma of a vacuum arc thruster allows the increased collimation of ions with the plasma plume and increases the thrust directed along the normal of the thrusters. The magnetic field is generated with a capacitive discharge coil which can achieve magnetic field strengths up to 300mT.The coaxial design of the Vacuum Arc Thruster allows for...
Jupiter is a quasi-stationary point source of energetic electrons, which are observed at Earth to display a thirteen month periodicity caused by the varying magnetic connection between Earth and the Jovian magnetosphere. The observation of Jovian electrons at Earth during times when Earth is not well magnetically connected to Jupiter implies that the electrons must have propagated across the...
Modelling solar energetic particles allows for the prediction of incoming solar radiation events as a way to protect against their potential harmful impact in space. Using omni-directional intensity and anisotropy data from the Solar Orbiter spacecraft for a solar event during December 2020, the particle transport in the turbulent interplanetary medium is simulated. The mean free path as a...
The South African advanced Super Dual Auroral Radar Network (SuperDARN) radar has been in operation for over the decade now and is located at South African National Antarctica Expedition (SANAE) station in Antarctica. SANAE radar scans the polar ionosphere over much of Antarctica, mainly to observe and study ionospheric plasma convection. SuperDARN is designed such that it can estimate the...
The skynoise data is monitored by the Super Dual Auroral Radar Network (SuperDARN). It is anticipated that during the periods of increased solar activity, the ionospheric ionization increases, which results in the absorption of radio signals in the ionosphere, hence there would be an expected attenuation of skynoise and interference of the SuperDarn radars signal. This study intended to...
The Super Dual Auroral Radar Network (SuperDARN) is an international collaboration of High Frequency (HF) radars located in the mid and high-latitude zones of
the northern hemispheres and the southern hemispheres. These HF radars operate
and transmit signals at a frequency ranging from 8-20 MHz, although in most cases
they are operational at frequencies between 10 and 14 MHz. In this study,...
This research study aims to establish the behavior of Equatorial Ionization Anomaly (EIA) during geomagnetic storms. To identify geomagnetic storms, criteria of Dst ≤ -30 nT, and where Kp ≥ 4 indices will be used. The dynamics of the EIA will be studied based on total electron content (TEC) data for the period of five years (2008 to 2013), TEC is derived from Global Navigation Satellite...
In this paper, an investigation of radiation dose enhancement during geomagnetic storms over South Africa will be presented. The radiation exposure during a solar storm at aviation altitude is of interest to the aircrew, the international civil aviation organization (ICAO), and the general public. During solar storms, the radiation environment can change drastically due to ground level...
Commercial aviation space is filled with intense particle radiation that poses a heath risk to the aviation industry. Measurements obtained using dosimetric instruments during commercial aircraft flights have shown that the radiation levels can exceed dosimetric health limits of ground level work places. However, most of these measurements are not conducted routinely and for specific flight...
Soil moisture is a critical parameter in the forecasting and assessment of weather-induced extreme events such as heatwaves, droughts and floods, which are likely to increase in both frequency and intensity as a consequence of the projected climate change in southern Africa. Understanding the potential impacts of climate variability/change on soil moisture is essential for the development of...
