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TOPIC: Ingredients for life


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RE: Ingredients for life
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Herschel Finds Possible Life-Enabling Molecules in Space

The Herschel Space Observatory has revealed the chemical fingerprints of potentially life-enabling organic molecules in the Orion nebula, a nearby stellar nursery in our Milky Way galaxy. Herschel is led by the European Space Agency with important participation from NASA.
The new data, obtained with the telescope's heterodyne instrument for the far infrared -- one of Herschel's three innovative instruments -- demonstrates the gold mine of information that Herschel will provide on how organic molecules form in space.

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'Ingredients for life' present on Saturnian moon

Some of 'the major ingredients for life' are present on one of Saturn's moons, according to UCL scientists.
A team from the Mullard Space Science Laboratory working on the Cassini-Huygens mission have found negatively charged water ions in the ice plume of Enceladus.

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Primodial Soup
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'Primodial Soup' theory for origin of life rejected in paper

For 80 years it has been accepted that early life began in a 'primordial soup' of organic molecules before evolving out of the oceans millions of years later. Today the 'soup' theory has been over turned in a pioneering paper in BioEssays which claims it was the Earth's chemical energy, from hydrothermal vents on the ocean floor, which kick-started early life.

"Textbooks have it that life arose from organic soup and that the first cells grew by fermenting these organics to generate energy in the form of ATP. We provide a new perspective on why that old and familiar view won't work at all. We present the alternative that life arose from gases (H2, CO2, N2, and H2S) and that the energy for first life came from harnessing geochemical gradients created by mother Earth at a special kind of deep-sea hydrothermal vent -- one that is riddled with tiny interconnected compartments or pores" - team leader Dr Nick lane from University College London.

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Uracil
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In a laboratory set up to simulate conditions in space, NASA scientists were able to produce uracil, a key component of RNA, which is found in the genetic makeup of all living organisms on Earth.
The experiment is part of a larger initiative to try to understand how the building blocks for life might have formed in space.

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Prebiotic molecules
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Title: Large prebiotic molecules in space: photo-physics of acetic acid and its isomers
Authors: Fabrizio Puletti, Giuliano Malloci, Giacomo Mulas, Cesare Cecchi-Pestellini

An increasing number of large molecules have been positively identified in space. Many of these molecules are of biological interest and thus provide insight into prebiotic organic chemistry in the protoplanetary nebula. Among these molecules, acetic acid is of particular importance due to its structural proximity to glycine, the simplest amino acid. We compute electronic and vibrational properties of acetic acid and its isomers, methyl formate and glycolaldehyde, using density functional theory. From computed photo-absorption cross-sections, we obtain the corresponding photo-absorption rates for solar radiation at 1 AU and find them in good agreement with previous estimates. We also discuss glycolaldehyde diffuse emission in Sgr B2(N), as opposite to emissions from methyl formate and acetic acid that appear to be concentrate in the compact region Sgr B2(N-LMH).

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Meteor impacts may have cooked up life on Earth
Studies have shown that most of the delivered organics would have decomposed through shock heating or aerodynamic interaction with the ambient atmosphere.
However, Seiji Sugita from the University of Tokyo, Japan, and Peter H. Schultz from Brown University, Providence, Rhode Island, US, suggest that some of the decomposed organics could have been revived through chemical reactions between the meteoritic matter and the ambient atmosphere during hypervelocity oblique impacts.

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Billions of years ago, comets may have ferried life-sustaining water to our planet's surface, but that may not be all that we should thank these dirty snowballs for. Researchers are simulating comet impacts to see if they might help proliferate the left-handedness in molecules that life on Earth depends upon.
There is evidence from meteorite studies that amino acids may have been delivered to Earth from space.


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Salty Origins for Early Earth Biomolecules
In a study presented at the European Planetary Science Conference in Potsdam, researchers proposed that salt deposits on the early Earth's volcanic coasts enabled the conversion of amino acids into other important molecules for the start of life.

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EPSC09/13: Could salt crusts be key ingredient in cooking up prebiotic molecule

German scientists investigating the complex chemical mixture thought to be present in the early Earth's oceans have found that amino acids can be 'cooked' into many other important chemical building blocks of life when embedded in salt crusts. Results of the laboratory experiments will be presented by Dr Stefan Fox at the European Planetary Science Congress in Potsdam, Germany, on Thursday September 17.
Approximately 4.5 - 3.8 billion years ago, the Earth was probably covered by a salty ocean, rich in organic compounds, dotted with active volcanic islands and short-lived continents. The team from the University of Hohenheim in Stuttgart has simulated some of the chemical processes that might have taken place along hot volcanic coasts during this Hadean era by evaporating solutions of artificial primordial seawater and then baking the salty residue in an atmosphere of nitrogen and carbon dioxide to volcanic temperatures of 350 degrees Celsius. They found that compounds such as pyrroles, which are contained in chlorophyll and haeme, are created.
The group's experiments show that interaction of amino acids with metal ions in the salt crusts fundamentally changes the thermal behaviour of the molecules, preventing them from turning into gas at high temperatures and allowing unexpected compounds to form.

"We embedded the amino acid DL-alanine in a salt crust mixture of sodium, calcium, potassium and magnesium chlorides and, after heating, we found that a compound formed with calcium salt chemically bonded to the amino acid. This particular compound has never been seen before and, although similar compounds are known to exist, we did not expect to see them in our experiments. This bond between the salt and the amino acid stabilizes the compound at high temperatures and prevents sublimation. Without the bond, pyrroles would not be able to form" - Dr Stefan Fox .

Source: European Planetology Network

-- Edited by Blobrana on Thursday 17th of September 2009 03:31:48 PM

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Naphthalene
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University of Georgia researchers show component of mothballs is present in deep-space clouds
Interstellar clouds, drifting through the unimaginable vastness of space, may be the stuff dreams are made of. But it turns out there's an unexpectedly strange component in those clouds, and it's not dreams but - mothballs?
Well, not exactly, but researchers from the University of Georgia have just shown for the first time that one component of clouds emitting unusual infrared light know as the Unidentified Infrared Bands (UIRs) is a gaseous version of naphthalene, the chief component of mothballs back on Earth. The UIRs have been seen by astronomers for more than 30 years, but no one has ever identified what specific molecules cause these patterns.
The discovery that a special kind of naphthalene with a single extra proton is out in space is important to those studying interstellar regions for many reasons. One of the most important is that the UIRs are associated with interstellar dust, and understanding the components of that dust could give clues to the origin of these mysterious voyagers. The new information may also provide insights into stellar lifecycles.

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