A Hole in Mars. The hole was discovered by chance in 2011 on images of the dusty slopes of Mars' Pavonis Mons volcano taken by the HiRISE instrument aboard the robotic Mars Reconnaissance Orbiter currently circling Mars.展开全文
Blue amber. When light is shone through it or reflected off a white surface behind it, it transmits the normal resiny colour. When viewed in sunlight or against a dark background, this blue glow appears. It is caused by fluorescence, with the UV component of the ambient light展开全文
This jelly is found in tropical and temperate waters around the world. It was named after stinging a man Robert King in 2002. King felt a mild initial sting, but was soon overcome with acute widespread pain. He was rushed to the nearby hospital where doctors failed to save life.展开全文
"CHINA. Shanghai. December 1948-January 1949. As the value of the paper money sank, the Kuomintang decided to distribute 40 grams of gold per person. With the gold rush, in December, thousands came out and waited in line for hours. . Ten people were crushed to death."展开全文
An aerial view shows summer houses flooded by water from the River Danube near the Bavarian village Deggendorf, southern Germany, on June 6, 2013. Germany pushed on with frantic efforts to secure saturated river dykes with sandbags on June 6, 2013展开全文