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Tuesday, 14 January 2014

Panspermia... An Origin of Life On Earth Theory


Comet ISON C2012
Cosmic Ancestry is a new theory pertaining to evolution and the origin of life on Earth. It holds that life on Earth was seeded from space, and that life’s evolution to higher forms depends on genetic programs that come from space. (It accepts the Darwinian account of evolution that does not require new genetic programs.) It is a wholly scientific, testable theory for which evidence is accumulating.
The first point, which deals with the origin of life on Earth, is known as panspermia — literally, “seeds everywhere.” Its earliest recorded advocate was the Greek philosopher Anaxagoras, who influenced Socrates. However, Aristotle’s theory of spontaneous generation came to be preferred by science for more than two thousand years. Then on April 9, 1864, French chemist Louis Pasteur reported his experiment disproving spontaneous generation as it was then held to occur. In the 1870s, British physicist Lord Kelvin and German physicist Hermann von Helmholtz reinforced Pasteur and argued that life could come from space. And in the first decade of the 1900s, Swedish chemist and Nobel laureate Svante Arrhenius theorized that bacterial spores, propelled through space by light pressure, were the seeds of life on Earth.
Mechanisms for panspermia include the deflection of interstellar dust by solar radiation pressure and extremophile microorganisms traveling through space within an asteroid, meteorite or comet.
Three popular variations of the panspermia hypothesis are:
  • Lithopanspermia (interstellar panspermia) – impact-expelled rocks from a planet’s surface serve as transfer vehicles for spreading biological material from one solar system to another.
  • Ballistic panspermia (interplanetary panspermia) – impact-expelled rocks from a planet’s surface serve as transfer vehicles for spreading biological material from one planet to another within the same solar system
  • Directed panspermia - the intentional spreading of the seeds of life to other planets by an advanced extraterrestrial civilization, or the intentional spreading of the seeds of life from Earth to other planets by humans
Panspermia does not provide an explanation for evolution or attempt pinpoint the origin of life in the Universe, but it does attempt to solve the mysteries of the origin of life on Earth and the transfer of life throughout the Universe.
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  • 19 May 1995: two scientists at Cal Poly showed that bacteria can survive without any metabolism for at least 25 million years; probably they are immortal.
  • 24 November 1995: The New York Times described bacteria that can survive radiation much stronger than any that Earth has ever experienced.
  • 7 August 1996: NASA announced fossilized evidence of ancient life in meteorite ALH 84001 from Mars.
  • 27 October 1996: geneticists showed evidence that many genes are much older than the fossil record would indicate. Subsequent studies have strengthened this finding.
  • 29 July 1997: a NASA scientist announced evidence of fossilized microscopic life forms in a meteorite not from any known planet.
  • Spring, 1998: a microfossil that was found in a meteorite and photographed in 1966, was recognized by a Russian microbiologist as a magnetotactic bacterium.
  • Fall, 1998: NASA’s public position on life-from-space shifted dramatically.
  • 4 January 1999: NASA officially recognized the possibility that life on Earth comes from space.
  • 19 March 1999: NASA scientists announced that two more meteorites hold even stronger fossilized evidence for past life on Mars.
  • 26 April 2000: the German team operating the mass spectrometer on NASA’s Stardust mission announced the detection of very large organic molecules in space. Nonbiological sources for organic molecules so large are not known.
  • 19 October 2000, a team of biologists and a geologist announced the revival of bacteria that are 250 million years old, strengthening that case that bacterial spores can be immortal.
  • 13 December 2000: a NASA team demonstrated that the magnetosomes in Mars meteorite ALH 84001 are biological.
  • June 2002: Geneticists reported evidence that the evolutionary step from chimps to humans was assisted by viruses.
  • 2 August 2004: Very convincing photos of fossilized cyanobacteria in a meteorite were reported by a NASA scientist.
  • 25 January 2005: J. Craig Venter endorses panspermia.
  • 10 May 2007: E. O. Wilson endorses panspermia.
  • 18 April 2008: Richard Dawkins endorses panspermia.
  • 7 April 2009: Stephen Hawking endorses panspermia.
  • 2 May 2009: Freeman Dyson speaks favorably about panspermia.

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