The largest diamond ever found is the Cullinan: a 3,106-carat rough diamond (about 621 g) discovered in 1905 at the Premier mine, South Africa. It was cut into 9 major stones; the largest, Cullinan I (Great Star of Africa, 530.2…
In short: The fastest running bird is the ostrich, reaching about 70 km/h over short distances. The fastest flying bird is the peregrine falcon, measured at 389 km/h in a hunting dive.BirdRegionTop running speedOstrichAfrica70 km/hEmuAustralia50 km/hRheaSouth America60 km/hRoadrunnerNorth America32 km/hThe…
In short: The second person to walk on the Moon was Buzz Aldrin. He stepped onto the lunar surface about 19 minutes after Neil Armstrong on 20 July 1969 during Apollo 11. The third crew member, Michael Collins, stayed in…
In short: The compass was invented in China; there is no single inventor. The first magnetic direction finders were lodestone “sinan” spoons of the Han dynasty (about 2nd century BC – 1st century AD), used for divination. The magnetised-needle compass…
In short: The sky is blue because sunlight is scattered by the nitrogen and oxygen molecules in the atmosphere. This is called Rayleigh scattering: short-wavelength blue light is scattered about 5–6 times more than long-wavelength red light, so blue light…
In short: The Sun’s visible surface (photosphere) is about 5,500 °C (10,000 °F) and its core is about 15 million °C (27 million °F). The Sun’s outer atmosphere, the corona, is far hotter than the surface and can reach 2…
In short: The first known coins were minted by the Lydians in Anatolia (western Turkey) in the 7th century BC. Paper money was invented in China: paper payment notes were used from the early 9th century, and the first government-issued…
