Life came from space

[Enjo]

Murchison meteorite recent study shows... :

http://www.space.com/scienceastronomy/080613-meteorite-life.html

 

[n0mad23]

Are you surprised, or is this an "I told you so"?

 

[Enjo]

neither

[EDIT]
I believe that if you asked the same question those scientists who spent hours on this research, trying to prove something, they'd start pondering whether they have lost their time or not.
Plus, if you're so confident about life's space origins, then how did the first life originate?

 

[n0mad23]

neither
Plus, if you're so confident about life's space origins, then how did the first life originate?

This is the most interesting part of the question, I think. Is the universe loaded in life's favor? It certainly seems that way. Naturally, all the conditions have to be just right, but the elements are there.

I'm not sure that I "buy" life's origin on Earth came from elsewhere, but in the larger scheme of things, it makes as much sense as other theories. I'm left wondering if we can ever know.

 

[bujin]

Plus, if you're so confident about life's space origins, then how did the first life originate?

Isn't the article saying that the meteorite carried some of the chemical compounds which are necessary for life, rather than saying the meteorite itself contained life?

In that case, the first life (in our case) would still have started on Earth, just using chemicals that came from space.

Of course, I'm no biologist, let alone an abiogenesisissisisst (or whatever they're called!), so I could be misreading it...

 

[James.Denholm]

Oh, come on! Everyone knows life started because the Probe needed something to study.

 

[Ghostrider]

Anyway, it should have been: "Life here began out there".

 

[Napes Weaver]

Might not life be a fundamental quality like gravity? Maybe mystery too...

 

[Linguofreak]

How do they know that this meteorite was not blasted off of Earth itself by some impact in the past? I know they've found meteorites that are supposed to have been blasted off of Mars.

 

[Thunder Chicken]

Something that always gets me is that the nascent Earth is talked about as if it existed in sterile isolation from space until the meteorites started coming in. The Earth itself is a collection of meteorites and space debris. 4 billion years ago, whatever was floating around in space also existed on Earth. Geologic processes since then have altered the constituents of our crust, but 4 billion years ago Earth didn't need to be 'seeded' - Earth was made of 'seeds'.

The open question is whether life actually came into being on Earth or in Space.
It seems that the building blocks of life are fairly ubiquitous, but life needs these blocks to incubate in a warm wet environment (i.e. Earth) for them to actually assemble.

 

[pattersoncr]

Might not life be a fundamental quality like gravity? Maybe mystery too...

And death and taxes

 

[MAraujo]

Three facts about life that make it seem very likely that the Earth was seeded:

1. Life is unique.
That is to say that all life on earth is the same. It might not seem like this is the case when you look around your backyard, but there is nothing alive on earth that is not some form of bacteria. Even the cells in your body are nothing more than communities of bacteria. If there was a time when the earth was volitile and reactive you'd expect to see some variety of life.

2. Life is left handed.
In nature, any 3d chemical compound (exept a perfectly symmetrical one) comes in two varietes: left and right, just like your hands, the same but opposite. All organic compounds produced by life are left handed. There's no reason why life couldnt equally be right handed but we just don't see that here. If life started here (all things being equal) it would have a high probability of forming both left and right varieties with no special preference.

3. Not enough time for evolution.
The most primitive life from 4 billion years ago has DNA that is only 70% of the complexity of the most complex life today. Evolutionary biologists today are confiedent that over geologic time DNA mutation rates are relatively constant.
To put it visually:

|--------------------| The complexity of life today
|--------------| The complexity of life 4 billion years ago
|---------| The complexity of life sometime before the Solar System

If you work out the rates it looks like you'd have to go back about 12 billion years, to see DNA as a relatively simple compound. This is almost reasonable in the scheme of the history of the universe.

 

[Urwumpe]

Also, it was shown already, that the basic chemicals for life can also form on Earth in huge quantities and in rather short time.

 

[Ghostrider]

You know, life here... Began out there.

Hello Gaius my old friend,
I've come to haunt you again
Because a vision is catwalking,
Bugged you while you were whining,
And the red-dressed chick that's planted in your brain
Still remains
Within the sound of Cylons...

Sorry, couldn't resist.

 

[Notebook]

By your command...

N.

 

[MAraujo]

Also, it was shown already, that the basic chemicals for life can also form on Earth in huge quantities and in rather short time.

Yes, but life is not made of anything special. The existence of amino acids doesn't translate directly to the incredible organization of biology. For example; you might find alot of old english words in a book, but thats a far cry from the complete works of Shakespeare. Its easy to think of life as some special kind of matter, rather it moves conservatively through matter like the classic newtonian model of energy. Lynn Margolis is an evolutionary biologist who has done some fascinating work in this field. I would recoment her book "What is Life?"

 

[Urwumpe]

For example; you might find alot of old english words in a book, but thats a far cry from the complete works of Shakespeare.

Even Shakespeare babbled around when he was a child.

 

[Ghostrider]

But he babbled in iambic pentameter.

 

[NukeET]

Even Shakespeare babbled around when he was a child.

Granted...but when is the room full of chimpanzees working away at typewriters are going to produce a sonnet?

 

[Urwumpe]

Granted...but when is the room full of chimpanzees working away at typewriters are going to produce a sonnet?

Well, if you reward them already for writing Britney Spears lyrics, there is the chance that they might evolve to write jokes for Jay Leno in about ten years. No idea how to make them evolve to write sonnets. Maybe we need to enforce the mating rituals of 15th century people on chimps.