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TOPIC: Ingredients for life
Blobrana


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Discovery of sugar in outer space may be clue to alien life
Scientists have detected an organic sugar molecule which is directly linked to the origin of life in a region of our galaxy where habitable planets could exist. The discovery, partly funded by the UKs Science and Technology Facilities Council (STFC), is published on the Astrophysical Journals website today.
The international team of researchers which included Dr Serena Viti (UCL Physics & Astronomy), as well as scientists from France, Italy and Spain detected the molecule using the Institut de RadioAstronomie Millimétrique (IRAM) radio telescope in France, with which the team was observing a massive star-forming region of space some 26,000 light years from Earth with high-angular resolution and at different wavelengths.

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Blobrana


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Title: The Chirality Of Life: From Phase Transitions To Astrobiology
Authors: Marcelo Gleiser, Sara Imari Walker

The search for life elsewhere in the universe is a pivotal question in modern science. However, to address whether life is common in the universe we must first understand the likelihood of abiogenesis by studying the origin of life on Earth. A key missing piece is the origin of biomolecular homochirality: permeating almost every life-form on Earth is the presence of exclusively levorotary amino acids and dextrorotary sugars. In this work we discuss recent results suggesting that life's homochirality resulted from sequential chiral symmetry breaking triggered by environmental events in a mechanism referred to as punctuated chirality. Applying these arguments to other potentially life-bearing platforms has significant implications for the search for extraterrestrial life: we predict that a statistically representative sampling of extraterrestrial stereochemistry will be racemic on average.

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Blobrana


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Could Life Have Started In Lump Of Ice?
The universe is full of water, mostly in the form of very cold ice films deposited on interstellar dust particles, but until recently little was known about the detailed small scale structure. Now the latest quick freezing techniques coupled with sophisticated scanning electron microscopy techniques, are allowing physicists to create ice films in cold conditions similar to outer space and observe the detailed molecular organisation, yielding clues to fundamental questions including possibly the origin of life.

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Blobrana


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Electrons put a new spin on chirality
Could radiation striking magnetic materials be responsible for the 'handedness' of biological molecules?
Low-energy spin-polarised electrons are produced when X-rays and other ionising radiation strike iron, nickel and other magnetic materials. These materials are relatively abundant and such interactions could have occurred in the early solar system.

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Blobrana


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Scientists have come up with an answer to the puzzling question of why life on Earth coincides with a momentous shift in the makeup of the universe.
According to a report by ABC News, research into finding an answer to this mystery was done by Ph.D. student Chas Egan and Charley Lineweaver from Australian National University.

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Blobrana


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Miller experiment
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Volcanoes May Have Provided Sparks of First Life
Researchers reanalyse classic Miller experiment to uncover role of volcanoes in early life on Earth

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Blobrana


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One of the most famous experiments of all time has just been found to have been even more successful than anyone realised. The Miller-Urey spark flask experiment could hold the key to the origin of life on Earth.
Jeffrey Bada of the Scripps Institution of Oceanography in California and colleagues re-analysed the original 50-year-old samples left by Stanley Miller of the University of Chicago, in 1953 and 1954. His was the first experiment ever to produce amino acids, the building blocks of proteins, from inorganic molecules and a spark of electricity.
Bada's team discovered more organic molecules than Miller had been able to detect, and also showed that a secondary experiment one that Miller carried out but never published offers the best clue to how life on Earth began some 4 billion years ago.

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Blobrana


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Left-handed amino acids
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Breslow and his colleagues made significant progress recently when they proved that the Murchison amino acids could transfer their left-handedness to otherwise symmetrical amino acids.
They then found that small degrees of chirality could be dramatically amplified in a water solution under conditions similar to the early Earth.
Their conclusion was that even the relatively limited number of additional left-handed amino acids in the meteorites could, under the right conditions, lead to a world where almost all amino acids and proteins end up left-handed.

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Blobrana


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Title: Stability of organic molecules against shocks in the young Solar nebula
Authors: Inga Kamp, Milica Milosavljevic

One of the fundamental astrobiology questions is how life has formed in our Solar System. In this context the formation and stability of abiotic organic molecules such as CH4, formic acid and amino acids, is important for understanding how organic material has formed and survived shocks and energetic particle impact from winds in the early Solar System. Shock waves have been suggested as a plausible scenario to create chondrules, small meteoritic components that have been completely molten by energetic events such as shocks and high velocity particle impacts. We study here the formation and destruction of certain gas-phase molecules such as methane and water during such shock events and compare the chemical timescales with the timescales for shocks arising from gravitational instabilities in a protosolar nebula.

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Blobrana


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Tons, perhaps tens of tons, of carbon molecules in dust particles and meteorites fall on Earth daily. Meteorites are especially valuable to astronomers because they provide relatively big chunks of carbon molecules that are easily analysed in the laboratory. In the past few years, researchers have noticed that most meteorite carbon are molecules called polycyclic aromatic hydrocarbons (PAHs), which are very stable compounds and are survivors.
PAHs are the most common carbon-rich compound in the universe. They are found in everything from distant galaxies to charbroiled hamburgers and engine soot. When they are first formed, or found in space, their structures resemble pieces of chicken wire, fused six-sided rings. However, when found in meteorites, these aromatic rings are carrying extra hydrogen or oxygen.
Scientists at NASA Ames Research Centre, Moffett Field, Calif. performed laboratory experiments that explain the process by which these meteoritic hydrocarbons attract the extra hydrogen and oxygen. They are very similar to the molecules identified as evidence of alien microbes in an earlier Science paper (McKay et al 1996).

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