DNA stable during atmospheric transit and re-entry

[bohm2]

The genetic material DNA can survive a flight through space and re-entry into Earth's atmosphere -- and still pass on genetic information...This study provides experimental evidence that the DNA's genetic information is essentially capable of surviving the extreme conditions of space and the re-entry into Earth's dense atmosphere.

DNA survives critical entry into Earth's atmosphere
http://www.sciencedaily.com/releases/2014/11/141126144150.htm

Full published article:
http://www.plosone.org/article/fetc....1371/journal.pone.0112979&representation=PDF

 

[Ygggdrasil]

This is not so surprising. A study from nearly a decade ago showed that bacterial spores can survive entry into the atmosphere on a meteorite:
http://www.ncbi.nlm.nih.gov/pubmed/16379527

 

[Ouabache]

So now these researchers have shown this to be the case, we may ponder the next logical question, is this how life orginaly arrived on Earth and populated our ancient oceans? hmmmm

 

[bohm2]

So now these researchers have shown this to be the case, we may ponder the next logical question, is this how life orginaly arrived on Earth and populated our ancient oceans? hmmmm

Or is life on Earth the original seed for life on other planets throughout the universe? That would be a pretty major long-shot. But life on Earth is ~ 3.8 billion years old. I wonder if some of the DNA from Earth past, hasn't reached some distant planet favourable to life?

 

[Danger]

I wonder if some of the DNA from Earth past, hasn't reached some distant planet favourable to life?

Other than possibly the dinosaur-extinction asteroid impact, I doubt that any event in Earth's history has been traumatic enough to eject such material into space in amounts large enough to have encountered any physical bodies. What little might have escaped is probably either still floating around or has been sucked into the sun.

 

[Fractuallized]

A rather large step to get from DNA to life.

 

[bohm2]

Other than possibly the dinosaur-extinction asteroid impact, I doubt that any event in Earth's history has been traumatic enough to eject such material into space in amounts large enough to have encountered any physical bodies. What little might have escaped is probably either still floating around or has been sucked into the sun.

Here is a piece discussing some of these possibilities:

The conclusion is that no potentially DNA/RNA life-carrying ejecta from another solar system in the general Galactic star field landed on Earth before life already existed on Earth, not even if microbial survival time in space is as long as tens of millions of years. However, if the Sun formed initially as a part of a star cluster, as is commonly assumed, we cannot rule out the possibility of transfer of life from one of the sister systems to us. Likewise, there is a possibility that some extra-solar planets carry life that originated in our solar system.

Natural Transfer of Viable Microbes in Space from Planets in the Extra-Solar Systems to a Planet in our Solar System and Vice-Versa
http://arxiv.org/ftp/arxiv/papers/0809/0809.0378.pdf

 

[Pythagorean]

A rather large step to get from DNA to life.

You can't be too sure. It's possible that it was the other way around: that it was a rather large step for life to get something as stable as DNA to depend on - previous to that, it could have been an "RNA world"

http://www.ncbi.nlm.nih.gov/books/NBK26876/

 

[Danger]

it could have been an "RNA world"

The entire CSI franchise would never have existed!

 

[Pythagorean]

The entire CSI franchise would never have existed!

I should clarify - I meant it may be the case that DNA evolved from an RNA world.

 

[Danger]

I meant it may be the case that DNA evolved from an RNA world.

Oh, okay. I've always thought that it came about that way. I guess that maybe I took an idle speculation as fact when I was a kid, and never realized that it wasn't established.