Karoo (crater) Karoo (crater) Karoo is an impact crater on the Asteroid 253 Mathilde, named for the Great Karoo Basin, a coal basin in South Africa. It is 33.4 kilometers in diameter and was the most prominent crater seen during NEAR Shoemaker's Flyby of the Asteroid. The critical crater diameter is the scale at which cratering “goes global” and results in a solitary distinct crater. All smaller craters—however large D might be—are local events. Mathilde is thus a particularly interesting case, since it is the largest asteroid imaged at sufficient resolution to show that its topography is clearly exogenic, governed by impacts.
Semi-arid climate Diego, California (at its main airport), which has cool summers for the latitude due to prevailing winds off the ocean (so the average annual temperature is below 18°C) but mild winters (average temperature in January, 14°C, and closer to the 18.0°C isotherm that separates tropical and subtropical climates than to the 0°C or −3°C isotherm for the coldest month that separates temperate and continental climates). </ref> Semi-arid climate A semi-arid climate or steppe climate is the climate of a region that receives precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-arid