Antarctic Mission to Look for Life in Sub-Glacial Lake»

Researchers from the British Antarctic Survey will drill 3km through ice sheet to take samples from Lake Ellsworth

It is a mission into the uncharted and unknown in search of the hardiest life forms on Earth. British engineers set off last week to explore a lake that has been isolated from the rest of the planet for hundreds of thousands of years three kilometers under the Antarctic ice.

Researchers from the British Antarctic Survey (BAS) will use a hot-water "drill" to cut through the ice cap to Lake Ellsworth, on the western Antarctic ice sheet. By sampling the contents of the lake, which is liquid because of the extreme pressure of the ice on top of it, they hope to find clues about the evolution of life.

The predominant mood among the scientists is one of intense curiosity. "We really don't know what to expect," said Martin Siegert of the University of Edinburgh, one of the principal investigators on the expedition. "Whether we will find lots of life, whether we'll find low levels of life on the edge of existence, or whether we'll find nothing."

In recent decades, scientists have found bacteria and other single-celled organisms that have evolved to live in conditions in which other life forms would struggle to survive, such as darkness or extreme temperatures or salinity. The scientists believe that Lake Ellsworth might be a haven for these so-called "extremophiles".

"There is [also] a chance that viruses might well be there, bacteria might well be there and other more complex forms, but we don't believe other macro-organisms are down there," said Siegert.

David Pearce, science coordinator at the BAS and part of the team that will make the measurements next year once the equipment is in place, said finding life in a lake that had been isolated from the rest of the biosphere for so long would reveal much about life on Earth, but "if we find nothing, this will be even more significant, because it will define limits at which life can no longer exist on the planet".

Whatever is found, it will shed light on the potential of life existing elsewhere in our solar system. Europa, one of the moons of Jupiter, has an icy crust with a liquid ocean underneath, and some astrobiologists think that life might be able to survive there. "If life is teeming in Lake Ellsworth, then we know it's a very good habitat and it might change our appreciation of other places, Europa included," said Siegert.

Lake Ellsworth will be the first of Antarctica's 387 known sub-glacial lakes to be sampled directly. "We don't know whether the lake is 100,000 years old, 400,000 years old or a million years old or older," said Siegert. "These are questions we need answers to."

All the equipment that will be sent into the lake will be pre-sterilised and bagged in clean rooms and laboratories in the UK. They will only be unsealed for use when they are in the boreholes – the samples of lake water, for example, will be brought up to the surface in pressurised titanium cylinders to preserve their contents.

The team will have 24 hours to take all they need before the bitter cold causes the water in the borehole to freeze solid and seal the lake once more.The engineers who will install the equipment left for the Antarctic on Friday, taking with them around 70 tonnes of equipment. In a year, the science team will follow and spend four days drilling and taking their samples.

"The detailed analyses will take place in the UK in the following months and it'll probably be, at the earliest, around Easter time [in 2013] before we would be prepared to tell everybody what's in there," said Siegert.

Antarctic Mission to Look for Life in Sub-Glacial Lake

http://www.guardian.co.uk/world/2011/oct/15/antarctic-mission-sub-glacial-lake#

The History of the Laser

It is one of the best examples of how technology can go from the science of the future to everyday use in a short period of time. Laser is short for Light Amplification by Stimulated Emission of Radiation. The idea behind lasers is complex. Just how complex? Consider that it took the mind of Albert Einstein to discover the physics behind the laser. Theodore Maiman succeed in building the first working laser in nineteen sixty. Mr. Maiman worked at Hughes Research Laboratories in Malibu, California.

​​ A laser fires a light beam. Before the laser, scientists developed a similar device: a maser which stands for Microwave Amplification by Stimulated Emission of Radiation. A maser is basically a microwave version of the laser. Microwaves are a form of electromagnetic radiation similar to, but shorter than, radio waves. The best-known use of masers is in highly accurate clocks. In the nineteen fifties, researchers in the United States and Russia independently developed the technology that made both masers and lasers possible. Charles Townes was a professor at the Massachusetts Institute of Technology in Cambridge, Massachusetts. He and his students developed the first maser. Russians Nicolay Basov and Aleksandr Prokhorov did their research in Moscow. Their work led to technology important to lasers and masers. The three men received the Nobel Prize in Physics in nineteen sixty-four.

The idea of a thin beam of light with deadly power came much earlier. By the end of the eighteen hundreds, the industrial revolution had shown that science could invent machines with almost magical powers. And some writers of the time were the first to imagine something like a laser. In eighteen ninety-eighty, H.G. Wells published a science fiction novel called “The War of the Worlds.” In it, he described creatures from the planet Mars that had technology far beyond anything on Earth. Among their weapons was what Wells called a “heat ray.” Laser light is different from daylight or electric lights. It has one wavelength or color. Laser light is also highly organized. Light behaves like a wave and laser light launches in one orderly wave at a time from its source.

The physics of the laser may be complex. Still, it is just a story of how electrons interact with light. When a light particle, or photon, hits an electron, the electron jumps to a higher energy state. If another photon strikes one of these high-energy electrons, the electron releases two photons that travel together at the same wavelength. When this process is repeated enough, lots of organized, or coherent, photons are produced. Industry put lasers to work almost immediately after they were invented in nineteen sixty. But weapons were not first on the list. The first medical operation using a laser took place the year following its invention. Doctors Charles Campbell and Charles Koester used a laser to remove a tumor from a patient’s eye at Columbia-Presbyterian Hospital in New York City. Since then, doctors have used lasers to cut and remove tissue safely with little risk of infections. Other health uses include medical imaging and vision correction surgery. Eye surgeons use lasers in LASIK operations to reshape the cornea, which covers the lens of the eye. The reshaped cornea corrects the patient’s bad eyesight so he or she does not have to wear glasses or other corrective lenses.

Lasers have made measurement an exact science. Astronomers have used lasers to measure the moon’s distance from Earth to within a few centimeters. Mappers and builders use laser technology every day. For example, drawing a perfectly level straight line on a construction site is easy using a laser. Energy researchers are using lasers in an attempt to develop fusion, the same energy process that powers the sun. Scientists hope fusion can supply almost limitless amounts of clean energy in the future. Manufacturers have used lasers for years to cut and join metal parts. And the jewelry industry uses lasers to write on the surface of the world’s hardest substance, diamonds. Laser barcode scanners have changed how stores record almost everything. They help businesses keep track of products. They help in storage and every detail of the supply process.

Lasers are found in many products used almost everywhere. Laser printers can print out forms and documents quickly and are relatively low in cost. They are required equipment for offices around the world. If you have a CD or DVD player, you own a laser. Laser disc players use lasers to accurately read or write marks on a reflective, coated plastic disc. A device turns these optical signals into digital information that becomes music, computer software or a full-length movie.

Over one hundred years ago, writers imagined that beams of light could be powerful weapons. Today, lasers guide missiles and bombs. For example, pilots can mark a target invisibly with a laser. Bombs or missiles then track the target with deadly results. And, yes, American defense companies are working on giant laser guns recognizable to science fiction fans everywhere. But there are technological difficulties. Scientific American magazine says huge lasers turn only about twenty to thirty percent of the energy they use into a laser beam. The rest is lost as heat.

That has not stopped scientists from working to perfect powerful lasers that, one day, may be able to shoot missiles out of the sky.

http://learningenglish.voanews.com/content/the-history-of-the-laser/1597831.html

Hadron Collider

The Large Hadron Collider (LHC) is the world's largest and highest-energy particle accelerator. It was built by the European Organization for Nuclear Research (CERN) from 1998 to 2008, with the aim of allowing physicists to test the predictions of different theories of particle physics and high-energy physics, and particularly prove or disprove the existence of the hypothesized Higgs boson and of the large family of new particles predicted by supersymmetric theories. The LHC is expected to address some of the still unsolved questions of physics, advancing human understanding of Physical laws. It contains six detectors each designed for specific kinds of exploration.

The LHC was built in collaboration with over 10,000 scientists and engineers from over 100 countries, as well as hundreds of universities and laboratories. It lies in a tunnel 27 kilometres (17 mi) in circumference, as deep as 175 metres (574 ft) beneath theFranco-Swiss border near Geneva, Switzerland.

The term hadron refers to composite particles composed of quarks held together by the strong force (as atoms and molecules are held together by the electromagnetic force). The best-known hadrons are protons and neutrons; hadrons also include mesons such as thepion and kaon, which were discovered during cosmic ray experiments in the late 1940s and early 1950s.

A collider is a type of a particle accelerator with directed beams of elementary particles. In particle physics colliders are used as a research tool: they accelerate particles to very high kinetic energies and let them impact other particles. Analysis of the byproducts of these collisions gives scientists good evidence of the structure of the subatomic world and the laws of nature governing it. Many of these byproducts are produced only by high energy collisions, and they decay after very short periods of time. Thus many of them are hard or impossible to study in other ways.