Solid light Solid light describes a method of obtaining a phase transition in light. At a critical point light crystallises. This form of light was not predicted! It is a new exotic state for light. Despite some precursor experiments, the idea is to create a system where this effect can be observed. This would consist of a trap where a single photon reacts with a single atom. Quantum Entanglement Quantum entanglement is a strange telepathic link which allows particles to influence each other´s properties. Some have suggested the power travels at millions of times the speed of light. The notion defies our notion of common sense. Einstein dismissed the theory as too spooky to be real. But entanglement is more than just a product of the equations of quantum theory. It exists and plays a part in the real world. It is at the forefront of a technological revolution. It can be used in encrypting information. It is unbreakable. The race is on to bring quantum cryptography to a worldwide market. It will be used to protect financial transactions and information flow. It will be used to drive quantum computers. Michael Brooks´ book, Entanglement is a thriller based on the power of entanglement falling into the wrong hands. How chromosomes split in cell division Kim Nasmyth uses an analogy of two blind men dividing coloured socks to explain how chromosomes divide in cell division. Not only does he describe the process, but Kim Nasmyth talks about what holds the chromosome pairs together prior to separation, and what causes the chromosomes to finally split apart. Voyager spacecraft on the outer edge of the solar system The Voyager spacecraft are at the outer edge of the solar system. Voyager 1 is at 105 astronomical units. Neptune is only at 30 astronomical units. (1 unit is the distance between the Earth and the Sun). Signals are received from the craft every day despite the transmitter on the craft being only 20 watts. The Voyager craft are expected to enter interstellar space in about 5 years time. Conditions outside the heliosphere are expected to be quite different from those within. Material floating around will be from other stars. The magnetic field will be different. Interstellar wind will be denser, and radio signals picked up by the craft should be stronger, with stronger cosmic rays. Energy for the craft, from the decay of plutonium will cool and power will run out some time after 2020. Dawn - mission to asteroids Vesta and Ceres Vesta and Ceres are the two biggest asteroids in the asteroid belt. Vesta is barren. Ceres is a mystery. We have no meteorites from Ceres. One in 20 meteorites that fall on the Earth are from Vesta. So why is there nothing from Ceres? Might the meteorites evaporate? Might they be made of water? Phytoplankton monitoring under threat Satellites are very important tools for studying phytoplankton in the oceans. They suck up nutrients from land runoff. They release oxygen and take up carbon dioxide. They support fish and regulate climate. In over 70% of the oceans, as waters warm, the amount of phytoplankton decrease. Michael Behrenfeld says we´re about to lose our ability to monitor phytoplankton. The workhorse satellite for sending phytoplankton data stopped working in Jan 2008. There is only one remaining satellite sending data. Tagging and studying bluefin tuna A tuna weighs 300Kg. Barbara Block describes how a tuna is caught, tagged and released. One tuna tagged off the United States swam for 4 years after being tagged. The tags were developed in Tasmania. Of the three species of bluefin tuna, the southern bluefin tuna, managed by Australia is in the worst condition. They are most severely affected by over-fishing. California has the only facility in the world where there are bluefin tuna in captivity. Feeding and providing space for such large fish presents some major challenges. Almost all the globe´s bluefin tuna catch goes to Japan. It is suggested Japan´s whaling activity is a way of diverting attention form the country´s tuna catch. Sharks under threat Sharks are disappearing from oceans around the world. In the north-west Atlantic, all great shark species have declined by 50% since the early 1970s. For some species the decline is higher. Some have declined by 98%. Sharks are caught for their fins. It´s a process which uses under 5% of the shark. The animal is then left to die. 38 million sharks are caught and `finned´ each year. Until recently, sharks were just caught as bycatch. An emerging trend is the targeting of sharks. They evolved 400 million years ago. Some species are now in danger of extinction, despite being found in vast areas of ocean.

[ Sat, 15 Mar 2008 00:00:00 +1000 ]

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