South Pole
In midsummer, as the sun reaches its maximum elevation of about 23.5 degrees, high temperatures at the South Pole in January average at . As the six-month "day" wears on and the sun gets lower, temperatures drop as well: they reach around sunset (late March) and sunrise (late September). In midwinter, the average temperature remains steady at around . The highest temperature ever recorded at the Amundsen–Scott South Pole Station was on Christmas Day, 2011, and the lowest was on June 23, 1982 (for comparison, the lowest temperature directly recorded anywhere on earth was at Vostok Station on July 21, 1983, though was measured indirectly by satellite in East Antarctica between Dome A and Dome F in August 2010). Mean annual temperature at the South Pole is -49.3 °C (-56.7 °F).
Karoo
Turning north from the N1 between Touws River and Beaufort West, at Matjiesfontein, the road ascends the Great Escarpment through the Verlatenkloof Pass to reach Sutherland, at 1456 m above sea level, which is reputedly the coldest town in South Africa with average minimum temperatures of -6.1 °C during winter. Parts of eastern the Mpumalangan Highveld do at times experience lower temperatures than Sutherland, but not as consistently as Sutherland does. Snowfalls are not infrequent during the southern winter months. The South African Astronomical Observatory has an emplacement of telescopes about 20 km east of the town, on a small plateau 1798 m above sea level, and is home to the Southern African Large Telescope, the largest optical telescope in the Southern Hemisphere. To the north, still on the Plateau, and 75 km north-west of Carnarvon, seven radio dishes form part of the Square Kilometer Array which will, 2500 in total, be scattered in other parts of South Africa and Australia, to survey the southern skies at radio frequencies. Our galaxy, the Milky Way, one of the main targets of this enterprise, is best viewed from the Southern Hemisphere.
The Upper Karoo is indeed an ideal site for an astronomical observatory. This is not only because of the clear skies, absence of artificial lights, and high altitude, but it is also tectonically completely inactive, meaning that there are no fault lines or volcanoes are nearby, so no earth tremors or earthquakes occur, even at great distances.