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NASA-funded astrobiology research has changed the fundamental knowledge about what comprises all known life on Earth.
Researchers conducting tests in the harsh environment of Mono Lake in California have discovered the first known microorganism on Earth able to thrive and reproduce using the toxic chemical arsenic. The microorganism substitutes arsenic for phosphorus in its cell components.
This finding of an alternative biochemistry makeup will alter biology textbooks and expand the scope of the search for life beyond Earth. The research is published in this week's edition of Science Express.


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Arsenic and Deep Space?

NASA's announcement today of the discovery of bacteria from Mono Lake, California, that can use arsenic in its body instead of being poisoned by it, is significant to the search for life on other worlds. Not only do these organisms live in an extreme environment -- but they are also an extreme life form.
If we can find such an extreme combination on Earth, what may have evolved in alien environments elsewhere?

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Arsenic-loving bacteria may help in hunt for alien life

The first organism able to substitute one of the six chemical elements crucial to life has been found.
The bacterium, found in a California lake, uses the usually poisonous element arsenic in place of phosphorus.
The find, described in Science, gives weight to the long-standing idea that life on other planets may have a radically different chemical makeup.
It also has implications for the way life arose on Earth - and how many times it may have done so.

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'Life as we don't know it' discovery could prove existence of aliens

The discovery could prove the theory of "shadow" creatures which exist in tandem with our own and in hostile environments previously thought uninhabitable.
The "life as we don't know it" could even survive on hostile planets and develop into intelligent creatures such as humans if and when conditions improve.
In a press conference scheduled for tomorrow evening, researchers will unveil the discovery of a microbe that can live in an environment previously thought too poisonous for any life-form to survive.
The bacteria has been found at the bottom of Mono Lake in California's Yosemite National Park which is rich in arsenic - usually poisonous to life.

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Astrobiology
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True believers are in a spin after a tantalising press release from NASA that says it has news to share about the search for alien life.
The space agency this week announced a media conference to "discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life".

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NASA Sets News Conference on Astrobiology Discovery

NASA will hold a news conference at 2 p.m. EST on Thursday, Dec. 2, to discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life. Astrobiology is the study of the origin, evolution, distribution and future of life in the universe.
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Chris Impey, when he's not helping to run the department of astronomy at the University of Arizona, researches the origin and evolution of galaxies.
When he's not doing that, he is thinking about how life might have evolved on this planet or on one of the billions of planets elsewhere in the universe.
Astrobiology, which studies those questions by harnessing the latest developments in the physical and earth sciences, is now the subject of two of Impey's books.

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There's an idea - common, but not popular in scientific circles - that all life on Earth was seeded from comets, asteroids or meteors which struck the planet and contained the building blocks necessary to kickstart the evolutionary process.
It's called "panspermia" and it caused an all-in boffin barney some 15 years ago when several scientists backed claims there was evidence of life in a Martian meteorite found in the Allan Hills in Antarctica.

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Title: Primordial planets, comets and moons foster life in the cosmos
Authors: Carl H. Gibson (Univ. Cal. San Diego US), N. Chandra Wickramasinghe (Univ. Cardiff UK), Rudolph E. Schild (Harvard US)

A key result of hydrogravitational dynamics cosmology relevant to astrobiology is the early formation of vast numbers of hot primordial-gas planets in million-solar-mass clumps as the dark matter of galaxies and the hosts of first life. Photon viscous forces in the expanding universe of the turbulent big bang prevent fragmentations of the plasma for mass scales smaller than protogalaxies. At the plasma to gas transition 300,000 years after the big bang, the 10^7 decrease in kinematic viscosity {\nu} explains why ~3x10^7 planets are observed to exist per star in typical galaxies like the Milky Way, not eight or nine. Stars form by a binary accretional cascade from Earth-mass primordial planets to progressively larger masses that collect and recycle the stardust chemicals of life produced when stars overeat and explode. The astonishing complexity of molecular biology observed on Earth is possible to explain only if enormous numbers of primordial planets and their fragments have hosted the formation and wide scattering of the seeds of life virtually from the beginning of time. Geochemical and biological evidence suggests that life on Earth appears at the earliest moment it can survive, in highly evolved forms with complexity requiring a time scale in excess of the age of the galaxy. This is quite impossible within standard cold-dark-matter cosmology where planets are relatively recent, rare and cold, completely lacking mechanisms for intergalactic transport of life forms.

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Red Dwarfs May Be Safe Havens For Life

Young red dwarfs have a petulant youth stretching over billions of years. Titanic stellar flares erupt without warning and blast out lethal doses of ultraviolet radiation. Ocean life on a planet may be safe from the UV just a few feet underwater and still extract enough light for photosynthesis. But anything living on the surface could get fried without a liberal coating of Sunscreen 2000.
But we now have a glimmer of hope for red dwarf planets. Astrobiologist Antigona Segura of the Universidad Nacional Autónoma de México (UNAM) in Mexico City, simulated how a 1985 flare from the nearby red dwarf AD Leonis would have affected a hypothetical Earth-like planet orbiting a dwarf.
He found that UV radiation actually split molecules of oxygen to create more ozone than it destroyed. The simulation made a thicker ozone layer in the planetary atmosphere such that the surface experienced no more radiation than is typical on a sunny day on Earth.

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