The South African National Space Agency (Sansa) announced on Wednesday that images of Sprites have been captured from the ground for the first time in South Africa. Sprites are visible gas discharges triggered by lightning, which shoot upwards from the tops of thunderstorm clouds to altitudes of between 50 km and 100 km and last for between one and ten milliseconds.
The images were taken on January 11 by a night-vision TV camera funded by the National Research Foundation (an agency of the Department of Science and Technology). The camera is an instrument of Sansa’s Optical Space Research (OSR) Laboratory, a state-of-the-art facility hosted by the South African Astronomical Observatory, at Sutherland in the Karoo region, in terms of a four-year agreement.
Despite the fact that they must be common – they are always initiated by large cloud-to-ground lightning strikes in major thunderstorms, of which there are millions every year – they are only rarely observed. “Despite being easily visible, nobody has ever reported seeing Sprites over Southern Africa,” pointed out Sansa Hermanus office chief scientist Professor Michael Kosch. “We are extremely excited to have finally captured the first images of Sprites over South African skies.”
“These observations pave the way for more comprehensive observations at multiple wavelengths to improve our understanding of how Sprites are triggered and their effects on the upper atmosphere,” stated University of Cape Town (UCT) Department of Electrical Engineering SpaceLab Professor Peter Martinez. The images were actually captured by UCT Masters student Nnadih Stanislaus. (Martinez is his supervisor.) “It was an amazing experience; seeing in real time what has never been recorded over Southern Africa,” enthused Stanislaus. “I felt like a hunter!”
The OSR Laboratory will also be used for research into atmospheric gravity waves. “We will be using the OSR initially to study atmospheric gravity waves that will provide us with greater insight into the dynamics of the Earth’s middle atmosphere,” explained Kosch. “Such knowledge is important because the middle atmosphere couples space weather from above to territorial weather below.”
Space weather is one of Sansa’s research areas. The OSR has unique capabilities that will allow the collection of critical space science data which will allow Sansa to fulfill both national and international obligations. It will also increase the standard of research in South Africa and promote scientific development, as well as provide data about currently unanswered scientific questions.