South Africa and Lesotho--a panorama
An astronaut aboard the International Space Station (ISS) looked toward the horizon as the spacecraft sped across southern Africa. The crew used a short lens that mimics closely what the human eye sees--a big panorama from a point over northern South Africa, looking southeast to the Indian Ocean. The image shows many details, one of the most striking of which is the political boundary defining the small country of Lesotho (dashed line, image center). This is one of the few places on Earth where a political boundary can be seen from space. The greener, more vegetated South Africa agricultural landscape, with a very low population density, contrasts with the less vegetated, tan-colored landscape of the Lesotho lowlands where more dense populations live. Lesotho is a small enclave of 2 million people completely surrounded by the Republic of South Africa (population 53 million).
The Katse Dam reservoir (image upper center), another detail in Lesotho, was built as part of an international agreement, to increase the water supply to the many, rapidly growing cities of the distant Witwatersrand (image lower left). In Africa's largest water transfer project, water from the high-rainfall zone in the mountains of Lesotho is fed from Katse through tunnels dug beneath the Maluti Mts. The water then flows 250 km in rivers to the Witwatersrand, South Africa's industrial heartland.
ISS crews can visually pinpoint the Witwatersrand by the scatter of small, but prominent, light-toned "mine dumps," the waste material remaining after the extraction of gold. The mine dumps are the main feature that crews can readily see because even large cities can be difficult to detect from space as the ISS rapidly flies past. More than 12.3 million people live in this major urban region.
One other detail stands out. A series of concentric lines indicates one of the Earth's oldest and largest visible impact craters. The Vredefort impact crater (image lower right, indicated by curved line) was caused by an asteroid estimated to have been 10 km in diameter that impacted the region ~1850 million years ago. The original crater is estimated to have been 300 km in diameter. Today it is eroded and partly obscured by younger rocks.