Friday, June 13, 2008

Life and Chirality an asymmetric universe.

As we previously posted on panspermia.

Panspermia did life come from outer space?

A vocal minority of biological investigators, including Nobel winner Francis Crick have put forward views stating that life as we know it ,did not commence here on Earth at all, but was imported from outerspace. Specifically that the ingredients and precursors such as spores or microorganisms from life bearing planets are transported across the Galaxy.

The first proponent of the Panspermia theory was chemist Svente Arrhinius .His view was the life bearing spores floated across space propelled by solar radiation .Francis Crick suggested it was transported on meteorites ,Fred Hoyle and Chandra Wickramasinghe suggested it was in the interstellar clouds that earth encounters on the grand precession that earth takes around the outer spiral of the Galaxy lasting some 150 million years.

The latter has some substance as the paleo records show “feast and famine’ in biodiversity and severe climatic oscillations ,due to changes in density in the interstellar medium.

We see some more interesting news.

Scientists have confirmed for the first time that an important component of early genetic material which has been found in meteorite fragments is extraterrestrial in origin, in a paper published on 15 June 2008.

The finding suggests that parts of the raw materials to make the first molecules of DNA and RNA may have come from the stars.

The scientists, from Europe and the USA, say that their research, published in the journal Earth and Planetary Science Letters, provides evidence that life’s raw materials came from sources beyond the Earth.

Because meteorites represent left over materials from the formation of the solar system, the key components for life -- including nucleobases -- could be widespread in the cosmos. As more and more of life’s raw materials are discovered in objects from space, the possibility of life springing forth wherever the right chemistry is present becomes more likely.”

Necessity and chance suggest the left chemistry is more likely in a left dominated universe where asymmetry(chirality) is more dominant(Galctic spirals,dna.etc).

“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.

The term Chiral is derived from the Greek name kheir meaning "hand" and apparently was coined by Lord Kelvin in his Baltimore Lectures on Molecular Dynamics and the Wave Theory of Light in which he stated ..."I call any geometrical figure, or group of points, chiral, and say it has chirality, if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself."
While the concepts of "asymmetry" were developed by J.H. van’t Hoff and J.A. Le Bel in 1874 following the resolution by Louis Pastuer of a mixture of tartaric acid salt isomers during the period 1848-1853, in which he picked out the differing crystal types by hand - doing so on the basis of the differing physical appearance of the salt crystals . Pastuer recognized that two of the isomers polarized light differently (one to the left and the other to the right) and that this must be due to an asymmetric grouping of atoms in the optically active molecules.

And here we see the fundamental reality of nature,the absence of linearity,that growth and form is heliophysical (chiral=helix)
always and everwhere.

Image above


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