01 Aug 15
Originally posted by sonhouseNot exactly. There are components of life everywhere in the universe, components that our life cannot be without. What is this to blow me away?
That report really blew you away, eh.
We have found amino acids in Orion Nebula. Does that mean that life comes from there? And now we have found 'pre-life molecules' on a comet? And this imply that life comes from there? Well... eh...
I am not impressed. The origin of life is not settled by this. Boggles the mind? Perhaps by some, but I want some more. If they found some DNA, then I would be impressed. But this...? No...!
01 Aug 15
Originally posted by FabianFnasyou can't go from prebiotic molecules to DNA on a comet. It is the clouds of stuff that evolves off the comet and entering the atmosphere of Earth and other planets that will seed those places and then it is up to the environment of those places to see if those prebiotic molecules can turn into life.
Not exactly. There are components of life everywhere in the universe, components that our life cannot be without. What is this to blow me away?
We have found amino acids in Orion Nebula. Does that mean that life comes from there? And now we have found 'pre-life molecules' on a comet? And this imply that life comes from there? Well... eh...
I am not ...[text shortened]... me, but I want some more. If they found some DNA, then I would be impressed. But this...? No...!
Nobody says there will be life directly on a comet or asteroid, just places that has energy sources like lightning or underwater high temperature sea vents or other sources of energy that can transform the prebiotic molecules to complex entities like RNA and DNA and such.
01 Aug 15
Originally posted by sonhouseWell, these pre-biotic molecules, can't they be formed on the surface of Earth too? It would be more likely, in my humble opinion.
you can't go from prebiotic molecules to DNA on a comet. It is the clouds of stuff that evolves off the comet and entering the atmosphere of Earth and other planets that will seed those places and then it is up to the environment of those places to see if those prebiotic molecules can turn into life.
Nobody says there will be life directly on a comet or ...[text shortened]... energy that can transform the prebiotic molecules to complex entities like RNA and DNA and such.
We have pre-biotic atoms, formed in Red Giants and super-novae, later producing life molecules. Does that mean that life came from them?
We have quarks, formed in the BigBang event, later producing atoms that life needs. Does that mean that life came from the BigBang itself?
No, life came into existance of Earth. That we know. The rest are speculations.
The interesting questions is - Where did the first life on Earth form? At the shore lines of the sea? At the deapths of the sea? In the crust? And what steps were needed to form the first DNA / RNA?
01 Aug 15
Originally posted by moonbusIf these components for life is not as rare as one thought before - isn't it likely that they were on the ground of Earth too? Why would they form in comets but not on Earth?
I think what this shows is that the components for making life are not as rare as some people might have thought, prior to this discovery. Sonhouse is right that the components alone are not sufficient; they also have to fall upon fertile ground.
My point is that we don't need to look too far. The problem is that the evidence on earthly ground is destroyed in the run of billions of years, but the surface of comets are still 'virgin'. This ends up with we just don't know, and we cannot know. We have found them, but we don't know if there were the same components on Earth at the life foming era.
01 Aug 15
Originally posted by FabianFnasComets are not quite virgin since they lose mass every time they get close to the sun so it is a constantly renewing surface.
If these components for life is not as rare as one thought before - isn't it likely that they were on the ground of Earth too? Why would they form in comets but not on Earth?
My point is that we don't need to look too far. The problem is that the evidence on earthly ground is destroyed in the run of billions of years, but the surface of comets are stil ...[text shortened]... found them, but we don't know if there were the same components on Earth at the life foming era.
04 Aug 15
Originally posted by sonhouseReally?
[b]you can't go from prebiotic molecules to DNA on a comet. It is the clouds of stuff that evolves off the comet and entering the atmosphere of Earth and other planets that will seed those places and then it is up to the environment of those places to see if those prebiotic molecules can turn into life.
This has been observed?
06 Aug 15
Originally posted by whodeyYou need energy sources of some kind to get molecules to form together into RNA and then DNA. That can happen on Earth through lightning, hydrothermal vents, even warming and cooling mud and clay.
Really?
This has been observed?
The temps on comets are way too low to get past a certain complexity, not much in the way of lightning on comets nor hydrothermal vents.
19 Aug 15
Originally posted by sonhouseImpacts also generate energy. See this, Ingredients plus energy in one swell foop:
You need energy sources of some kind to get molecules to form together into RNA and then DNA. That can happen on Earth through lightning, hydrothermal vents, even warming and cooling mud and clay.
The temps on comets are way too low to get past a certain complexity, not much in the way of lightning on comets nor hydrothermal vents.
http://www.bbc.com/news/science-environment-33988456
19 Aug 15
Originally posted by moonbusImpacts add energy but that is a one off event, maybe happening a number of times per year but I would think other sources of energy like hydrothermal vents or lightning strikes will provide a more predictable and longer lasting energy source. Lightning probably provides something like the same amount of energy per strike as a physical meteorite but I would think there would be a lot more lightning strikes per given unit area over time as meteorites.
Impacts also generate energy. See this, Ingredients plus energy in one swell foop:
http://www.bbc.com/news/science-environment-33988456