Mes: febrero 2011

A meteorite found in Antarctica could lend weight to the argument that life on Earth was aided by an extraterrestrial body, scientists claim.

Chemical analysis of the meteorite shows it to be rich in the gas ammonia, which contains the element nitrogen – found in the amino and nucleic acids which form the basis of life.

Analysis of other meteorites has revealed organic compounds which the authors of the new paper believe are too complex to have played a role.

Details of the study by researchers at Arizona State University and the University of California, Santa Cruz, are published in the journal Proceedings of the National Academy of Sciences.

The new study is based on analysis of just under 4g of powder extracted from a meteorite called Grave Nunataks 95229 (named after its place of discovery in Antarctica).

The meteorite was found in 1995 and belongs to the “Renazzo” family of “carbonaceous chondrite” meteorites, a group of meteorites that retain much of their original composition and have not been melted by their parent body. They can contain high proportions of water and organic compounds.

The powder sample was shown to contain abundant amounts of ammonia as well as hydrocarbons (including the amino acids glycine and alanine).

Analysis of the isotopes of nitrogen and hydrogen found within the sample suggest the material originated from a “cold cosmic” environment, and were not the result of Earthly contaminants.

Researchers working at the Large Hadron Collider have said they expect to discover the Higgs boson particle by the end of 2012.

If the LHC does not turn up evidence of the Higgs during this run, physicists say they may have to significantly alter their views of physical laws.

The Higgs boson particle explains why other particles have mass, but it has not yet been observed by physicists.

The LHC is housed in a 27km-long tunnel under the French-Swiss border.

It smashes together proton particles travelling at close to the speed of light in a bid to uncover secrets of the Universe.

“It took human navigators centuries to figure out how to determine longitude on their long-distance voyages”.

Loggerhead hatchlings, however, are able to mange this feat as soon as they reach the sea from their nests.

On reaching the sea, the hatchlings are able to establish the correct course to the open ocean.

The young loggerheads then spend several years successfully navigating complex migratory routes over thousands of miles of ocean.

To carry out the research loggerhead hatchlings from Florida were placed in circular water containers and tethered to electronic tracking systems to monitor their swimming direction.

The hatchlings were then exposed to magnetic fields which replicated the fields they would come across in two locations on the same latitude but different longitude along their migratory route.

The turtles reacted to each magnetic field by swimming in the directions that would, in the real location, take them along their circular migratory route.

The researchers say this shows that the hatchlings are able to determine longitude using information from the magnetic field.