April 21, 2008 at 9:54 pm #28161
“NASA Discovers Life’s Building Blocks Are Common in Space”
“Life’s Building Blocks Abundant in Space”
“Meteorites Made Life Left-Handed”
“These meteorites were bringing in what I call the ‘seeds of chirality,’ stated Breslow. ‘If you have a universe that was just the mirror image of the one we know about, then in fact, presumably it would have right-handed amino acids. That’s why I’m only half kidding when I say there is a guy on the other side of the universe with his heart on the right hand side.’
These amino acids “seeds” formed in interstellar space, possibly on asteroids as they careened through space. At the outset, they have equal amounts of left and right-handed amino acids. But as these rocks soar past neutron stars, their light rays trigger the selective destruction of one form of amino acid. The stars emit circularly polarized light-in one direction, its rays are polarized to the right. 180 degrees in the other direction, the star emits left-polarized light.”
“In a report at the 235th national meeting of the American Chemical Society, Ronald Breslow, Ph.D., University Professor, Columbia University, and former ACS President, described how our amino acid signature came from outer space.
similar material at: http://www.sciencedaily.com/releases/2008/04/080406114742.htm
“Life In The Universe Takes Orders From Space”
“Pizzarello and Weber report in Science that in fact their experiment succeeded in proving this possibility. In the laboratory, when performing sugar syntheses in water, using reactions that modeled what may have existed on the early Earth, the asymmetry in the amino acids led to a similar asymmetry in the sugars. Pizzarello and Weber thus were able to conclude that the delivery of material from outer space via meteorites – despite the seeming randomness and complexity of these materials – could in fact have “pushed” chemical evolution on Earth toward homochirality.”
“NASA Scientist Finds Some Meteorites Not Sugar-Free”
Scientists have long believed meteorites and comets played a role in the origin of life. Raining down on Earth during the heavy bombardment period some 3.8 billion to 4.5 billion years ago, they brought with them the materials that may have been critical for life, such as oxygen, sulfur, hydrogen and nitrogen. Sugars and the closely related compounds discovered by Cooper, collectively called “polyols,” are critical to all known life forms. They act as components of the nucleic acids RNA and DNA, constituents of cell membranes and cellular energy sources.”
“This discovery shows that it’s highly likely organic synthesis critical to life has gone on throughout the universe,” said Kenneth A. Souza, acting director of astrobiology and space research at Ames. “Then, on Earth, since the other critical elements were in place, life could blossom.”
“Extraterrestrial Enigma: Missing Amino Acids In Meteorites”
“Amino acids have been found in interstellar clouds and in meteorites but with some enigmatic omissions and tantalizing similarities to life on Earth. Just why some amino acids are present in meteorites and others are absent, and why they seem to prefer the same “left-handed” molecular structure as Earth’s living amino acids are questions that could unravel one of the most fundamental questions of science: Where and how did life begin?
“The bottom line is that you have these materials that come from space,” says Steve Macko, professor of environmental sciences at the University of Virginia in Charlottesville. Macko refers specifically to eight of the amino acids found in a certain kind of meteorite a carbonaceous chondrite. All eight amino acids are identical to those used by life on Earth. That could seem to point to a cosmic origin of these basic biological building blocks, says Macko. The case is bolstered by the fact that early Earth was bombarded with meteorites and the amino acid glycine has been detected on interstellar molecular clouds.”
Life’s Building Blocks From Space? Meteorites A Rich Source For Primordial Soup
“Partial Ingredients for DNA and Protein Found Around Star”
“NASA’s Spitzer Space Telescope has discovered some of life’s most basic ingredients in the dust swirling around a young star. The ingredients – gaseous precursors to DNA and protein – were detected in the star’s terrestrial planet zone, a region where rocky planets such as Earth are thought to be born.”
“Here on Earth, the molecules are believed to have arrived billions of years ago, possibly via comets or comet dust that rained down from the sky. Acetylene and hydrogen cyanide link up together in the presence of water to form some of the chemical units of life’s most essential compounds, DNA and protein. These chemical units are several of the 20 amino acids that make up protein and one of the four chemical bases that make up DNA. ”
“Did Life Begin In Space? New Evidence From Comets”
“The 2005 Deep Impact mission to Comet Tempel 1 discovered a mixture of organic and clay particles inside the comet. One theory for the origins of life proposes that clay particles acted as a catalyst, converting simple organic molecules into more complex structures. The 2004 Stardust Mission to Comet Wild 2 found a range of complex hydrocarbon molecules – potential building blocks for life.”
“Pre-life Molecules Present In Comets”
“Studies of comets are thought to provide a “fossil” record of the conditions that existed within the gas cloud that collapsed to form the solar system a little more than 4.6 billion years ago. In this cloud, since nitrogen was thought to be in molecular form, and it follows that comets should contain molecular nitrogen as well.”
“Comets Spread Earth-life Around Galaxy, Say Scientists”
” The solar system could, therefore, be surrounded by an expanding ‘biodisc’, 30 or more light years across, of dormant microbes preserved inside tiny rock fragments. In the course of Earth history there may have been a few dozen close encounters with star-forming nebulae, during which microbes might be injected directly into young planetary systems.
“If planets capable of sustaining life are sufficiently common in the Galaxy, the Cardiff based scientists conclude that this mechanism could have infected over 10,000 million of them during the lifetime of our Galaxy. ”
“Scientists find clues that the path leading to the Origin of Life begins in Deep Space”
“This is the first direct evidence for the presence of complex, prebiotically important, biogenic compounds in space and brings us a step closer to assessing if life’s origin on Earth may have had a helping hand from infalling stardust. The bulk of the astronomical evidence points to the formation of these nitrogen containing PAHs in the winds of dying stars which inject them into interstellar space. Eventually they become incorporated into the clouds of material that give birth to stars and planets. Freshly formed planets continue to collect infalling material (dust, asteroids, meteorites, and comets) from the star formation process and life on Earth is thought to have emerged from this primordial chemical soup.”
same basic material from http://www.space.com/scienceastronomy/051018_science_tuesday.html
“So far evidence suggests that PANHs are formed in the winds of dying stars and spread all over interstellar space.”
“This stuff contains the building blocks of life, and now we can say they’re abundant in space,” Hudgins said. “And wherever there’s a planet out there, we know that these things are going to be raining down on it. It did here and it does elsewhere.”
same basic material from http://nai.arc.nasa.gov/news_stories/news_detail.cfm?ID=207
“Duplicating the harsh conditions of space in their laboratory, NASA scientists have created primitive cells with membrane-like structures. These chemical compounds may have played a part in the origin of life.”
“Scientists believe the molecules needed to make a cell’s membrane, and thus for the origin of life, are all over space. This discovery implies that life could be everywhere in the universe,” said Dr. Louis Allamandola, the team’s leader.
“Scientists discover sugar molecules in space”
“A team of scientisits has detected molecules of glycolaldehyde, a type of sugar, within a cloud at the center of our galaxy. Glycolaldehyde is a simpler compound than common table sugar. Molecules of glycolaldehyde can combine to form the sugar ribose. Ribose is a building block of DNA and RNA, which form the genes of all known living things. Sugars, DNA, and RNA are among the organic compounds (compounds that contain carbon) essential to life.
Giant clouds of gas and dust are the birthplace of stars and planets, including the Earth.The presence of sugar molecules within an interstellar cloud means that the chemicals necessary for life may be readily available to newly formed planets. The organic compounds might be carried to a planet’s surface by comets. ”
“Meteorites a Rich Source for Primordial Soup”
paper at: http://arxiv.org/abs/0803.0743v2
“Scientists from NAIs Carnegie Institution of Washington Team have a new paper in Meteoritics and Planetary Science detailing their discovery of amino acids in two meteorites at concentrations ten times higher than levels previously measured in other similar meteorites. The result suggests that the early solar system was far richer in the organic building blocks of life than scientists had thought, and that fallout from space may have spiked Earths primordial broth.”
“Cosmic ‘DNA’: Double Helix Spotted in Space ”
“Massive central black holes are the best sources for both the strong magnetic field and rotating body, and since most large galaxies have them, Morris expects DNA-like nebula may be common through out the universe.
“I absolutely expect to see [this configuration] in gas-rich galaxies with all these elements in place,” Morris said.”
“NASA Scientists Create Amino Acids in Deep-Space-Like Environment”
“A team of scientists at the NASA Astrochemistry Laboratory today announced that they had created amino acids in conditions mimicking deep space. Amino acids are the basic components of proteins, from which all life is made. According to researcher Max Bernstein, “We found that amino acids can be made in the dense interstellar clouds where planetary systems and stars are made. Our experiments suggest that amino acids should be everywhere, wherever there are stars and planets.”
The three amino acids produced in the Astrochemistry Lab are similar to those found previously in certain meteorites. Meteorites are pieces of asteroids or comets. The chemical similarities may indicate that amino acids were made in deep space, before the solar system formed, then eventually fell to Earth in meteorites. “This finding suggests that Earth may have been seeded with amino acids from space in its earliest days,” said team member Jason Dworkin, adding, “[T]his increases the odds that life also evolved in places other than Earth.”
In their deep-space simulator, the Astrochemistry Lab team has previously produced cell-membrane-like structures and other organic compounds basic to life. Next, they plan to investigate why left- and right-handed amino acids exist in space, but only the left-handed forms are used by life on Earth. Other scientists on the team include Lou Allamandola, George Cooper and Scott Sandford.”
“Previously, the team demonstrated that irradiating interstellar ice look-alikes generated compounds called amphiphiles that can organize themselves to form membranes; and molecules called quinones that play important roles in the metabolism of all living organisms on Earth. The next step, they say, will be to tackle the issue of left- and right-handed amino acids. Both forms exist in space, but only the left-handed forms are used by life on Earth.”
“VARIATIONS IN THE PEAK POSITION OF THE 6.2 m INTERSTELLAR EMISSION FEATURE:
A TRACER OF N IN THE INTERSTELLAR POLYCYCLIC AROMATIC
“Physicists Discover Inorganic Dust With Lifelike Qualities”
“Could extraterrestrial life be made of corkscrew-shaped particles of interstellar dust? Intriguing new evidence of life-like structures that form from inorganic substances in space have been revealed in the New Journal of Physics. The findings hint at the possibility that life beyond earth may not necessarily use carbon-based molecules as its building blocks. They also point to a possible new explanation for the origin of life on earth.”
“V.N. Tsytovich of the General Physics Institute, Russian Academy of Science, in Moscow, working with colleagues there and at the Max-Planck Institute for Extraterrestrial Physics in Garching, Germany and the University of Sydney, Australia, has studied the behaviour of complex mixtures of inorganic materials in a plasma. Plasma is essentially the fourth state of matter beyond solid, liquid and gas, in which electrons are torn from atoms leaving behind a miasma of charged particles.”
“He adds that the plasma conditions needed to form these helical structures are common in outer space. However, plasmas can also form under more down to earth conditions such as the point of a lightning strike. The researchers hint that perhaps an inorganic form of life emerged on the primordial earth, which then acted as the template for the more familiar organic molecules we know today.”
“Self-assembling amphiphilic molecules: Synthesis in simulated interstellar/precometary ices”
“We report here that a complex mixture of molecules is produced by UV photolysis of realistic, interstellar ice analogs, and that some of the components have properties relevant to the origin of life, including the ability to self-assemble into vesicular structures.”
Life-like Cell Walls Created in Deep Space Lab Conditions
“Scientists at NASA’s Ames Research Center and the University of California Santa Cruz duplicated the conditions of interstellar clouds of gas and dust, which are the birthplaces of stars. They combined ordinary chemicals common on Earth and in space — including water, ammonia, carbon monoxide and methanol — and chilled the mix to near absolute zero (minus 441 degrees Fahrenheit or minus 253 degrees Celsius).
The chemicals froze into thin bits of ice. Then, just as a star floods an interstellar cloud with ultraviolet radiation, the researchers zapped their chemical soup with UV rays.
The icy mix transformed into more complex chemical compounds, as expected. But what happened next was a surprise. ”
Official Paper via National Academy of Sciences: http://www.pnas.org/cgi/reprint/98/3/815.pdf
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