Life's Raw Materials May Have Come From The Stars, Scientists Confirm

[muriel_volestrangler]

ScienceDaily (Jun. 13, 2008) — 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 team discovered the molecules in rock fragments of the Murchison meteorite, which crashed in Australia in 1969.
...
The analysis shows that the nucleobases contain a heavy form of carbon which could only have been formed in space. Materials formed on Earth consist of a lighter variety of carbon.

http://www.sciencedaily.com/releases/2008/06/080613092514.htm

A TV report I saw said there was more carbon 13 than you'd find in a terrestrial sample.

[Cleita]

1. Didn't Carl Sagan say the same thing, to wit, we are made of the stars, thirty years ago? n/t

[muriel_volestrangler]

2. That's different - that's about the heavier elements all being produced

in fusion from earlier stars. Though, that was worked out by Fred Hoyle:

We are stardust.

Fred Hoyle was born in 1915 in Yorkshire and studied mathematics and astronomy at Cambridge University. He completed his degree just as the Second World War began and he married Barbara in the same year. During the war he helped develop radar for use on ships. At the same time he worked on a problem that had troubled scientists for years - what happens in stars? Hans Bethe had already suggested how hydrogen atoms were fused into helium at the tremendous temperatures and pressures in the core of stars. Hoyle developed Bethe's ideas and explained how when a star has almost used up its supply of hydrogen the fusion reactions instead turn helium into carbon and other elements. Later even heavier elements are formed right up to iron. At the end of a star's life these elements are blown out into space. Hoyle worked out that when very large stars explode in a supernova the elements heavier than iron are formed. So all the elements found on Earth and elsewhere in the universe have been formed in stars.

http://www.longman.co.uk/tt_secsci/resources/scimon/hoyle/hoyle.htm

As that page also says, Hoyle also originated the term 'Big Bang', to derisively refer to the idea of an initial 'explosion' of the universe, rather that his preferred Steady State theory (that was before the background radiation evidence).

But, coming back to life (or the building blocks of life) originating outside the Earth, Hoyle also supported the idea of 'panspermia':

Later in his life he pursued another controversial idea that Svante Arrhenius had developed one hundred years before - "panspermia". Hoyle was convinced that life exists throughout the universe and that bacteria and viruses carried by comets brought life to Earth millions of years ago . Hoyle thought that the process was still going on and that new viruses arriving from space cause epidemics of 'flu. He collected statistical and astronomical evidence that seemed to back up his theories but few scientists agreed with him. Nevertheless his outspoken views continued to interest the media and right up to his death he was busy trying to find support for his ideas.

So this would be a bit more of a justification for his ideas. While he was very right about the origin of the heavier elements, some think he would have shared in the Nobel prize for that work, if his support of the steady state theory and panspermia hadn't place him far outside the scientific mainstream in other respects.

[sakabatou]

3. Well yeah

without the supernovae blowing out carbon into planetary disks, we wouldn't be here.

[muriel_volestrangler]

4. Again, this is about the nucleobases

forming in space, not the formation of the atoms.

[sakabatou]

5. So this is proving abiogenesis in a way

[muriel_volestrangler]

6. Yes, the question of the origin of life on the Earth is still unresolved

and it's unclear how easy it would be for all of the components needed to have formed in the same environment. If some did actually form in a different environment (eg some in space, some in the ocean - with the ones in space arriving suddenly in the form of a meteorite), that might explain how things got started. Early days for this, though - it'll be interesting to see the reactions of people in that sphere.