The tragedy unfolded unusually slowly for an aviation catastrophe: The crew fought to control the USS Macon for more than an hour. US naval officers threw fuel canisters overboard in an attempt to reduce the weight of their vessel. The canisters imploded on their way to the ocean floor. Meanwhile, the Macon -- the largest rigid airship ever constructed in the United States -- sank inexorably downward, the safety of the Moffett Field hangar just within reach.

The Macon hit the water surface only five kilometers (three miles) off the Californian coast, along the latitude of the Point Sur lighthouse near Monterey, on Feb. 12, 1935. The zeppelin broke apart and sank into the deep water. Two of the 83 crew members died -- the low number of deaths is likely due to the fact that the Macon sank in slow motion.

Diatoms are unicellular algae that are native in many waters. They are a major component of marine phytoplankton and the food base for a large variety of marine organisms. In addition, they produce about one fifth of the oxygen in the atmosphere and are therefore a key factor for our global climate. However, these algae, which measure only a few micrometers, have yet another amazing ability: they can "smell" stones.

Jellyfish blooms are increasingly causing problems. In Korea, the number of accidents and financial losses caused by jellyfish is estimated at 300 billion won (£1.8 m) per year. To combat the jellyfish, Korean researchers led by Professor Hyeon Myeong are using a team of robots, called JEROS (Jellyfish Elimination Robotic Swarm). These slash and grind the jellyfish, killing 900 kg an hour.

Jellyfish cause the fishing industry to lose money by breaking fishing nets. They sting swimmers. They block the seawater cooling systems of power plants. In 2009, a ten-ton Japanese trawler capsized after the three man crew tried to haul up a net loaded with jellyfish.

The Mauve Stinger, or Luminescent Jellyfish, is a beautiful jellyfish. Often coloured purple, you can find it around the world in warm and temperate waters from around 12 to 30 m.

This jellyfish is the most venomous in the Mediterranean. However, its sting is usually limited to the skin surface with local pain which lasts for one to two weeks. In some cases the sting can leave scars, or pigmentation of the skin lasting for several years. Should you be stung by a jellyfish, rinse the area with vinegar for 30 minutes. If vinegar is not available use sea water: don’t use fresh water. Remove any tentacles left on the skin.

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