1. Department of Physics, North-West University, Mafikeng, South Africa
2. Center for Space Research, North-West University, South Africa
3. Astronomy and Astrophysics Division, Entoto Observatory and Research Center, Addis Ababa, Ethiopia
4. Department of Physics, College of Science and Technology, University of Rwanda, Kigali, Rwanda
5. Gravity and Cosmology Group, Department of Mathematics and Applied Mathematics, University of Cape Town, Cape Town, South Africa