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[RedKing]

The part that blew my mind was this:

Two of the carbonaceous chondrites contained a diverse array of nucleobases and structurally similar compounds known as nucleobase analogs. Intriguingly, three of these nucleobase analogs are very rare in Earth biology, and were not found in soil and ice samples from the areas near where the meteorites were collected at the parts-per-billion limits of their detection techniques.

After doing some quick and painful Wikipedia self-edumacation....holy shit. Essentially, you know all those letters you learned for amino acids in DNA, the part that's the actual "genetic code". GATTACATGAT and so forth? Well, this is saying "Yeah, we found G and T and C, and we also found some Q and Z and Þ and Ω." Geneticists already knew there were some "novel base-pairs" that could be used to 'extend' the genetic code beyond what's found in nature, in the same way that funky letters like the last two 'extend' the Latin alphabet for certain languages.

My mind just boggles at the idea of life that could regularly incorporate novel base-pairs into its own DNA. And as Aqizzar pointed out, the bigger implication is that if this stuff is on rocks floating around in space, it's almost a mathematical certainty that at least some other planets have been "seeded" with organic molecules.

[Dsarker]

But what that also means is that it is extremely unlikely that that meteorite was the source of life on earth.

How likely is it that a meteorite was the source of life on earth, anyway? I heard somewhere that the chance of a single amino acid forming was nigh on impossible.

[RedKing]

But what that also means is that it is extremely unlikely that that meteorite was the source of life on earth.

Not necessarily. Just means that this particular collection of amino acids likely wasn't. Different rocks could have different batches of acids, and for that matter we know so little of how life was formed that it's possible that the novel base pairs (which do exist on Earth in small amounts, just not in living DNA that we've found) just aren't as amenable to self-organization or any number of other reasons why our DNA doesn't have these funky bases in it.

How likely is it that a meteorite was the source of life on earth, anyway? I heard somewhere that the chance of a single amino acid forming was nigh on impossible.

Odds for a single event are astronomically low. However, you're talking about astronomical scales of time. A very rare event X an obscenely large number of attempts over cosmological timeframe = Meh...maybe 50%?

To put it another way, the odds of rolling 20 6's in a row on standard dice is incredibly low (about 1 in 3.6 quadrillion). But if you rolled dice constantly for 300 million years, odds are it would happen at least once.

[kaijyuu]

My analogy for it is this:

The chance of life spontaneously arising from a situation where all the base building blocks are present is similar to dumping a box of Legos off the side of a building and having it be fully assembled after hitting the ground. Incredibly unlikely, yes, but what if you do it millions of times a second over 3 billion years?

[counting]

Some knowledge gap between organic chemistry with biochemistry. Organic biochemistry is just a very selective certain organic chemistry processes. Why weren't there more is hard to study. Since we just know one kind. Human gets a lot to learn about what's the process of life.

[RedKing]

More cool shit...IN SPACE!

Thin belt of antimatter found in Earth orbit

Not all that significant AFAIK, but still damned cool.

[alway]

How likely is it that a meteorite was the source of life on earth, anyway? I heard somewhere that the chance of a single amino acid forming was nigh on impossible.

Amino acids have been found pretty often in space. Usually it's the more simple ones; but that they would form is certainly not rare. After all, they're made up of essentially the most common atoms in the universe.

[woose1]

My analogy for it is this:

The chance of life spontaneously arising from a situation where all the base building blocks are present is similar to dumping a box of Legos off the side of a building and having it be fully assembled after hitting the ground. Incredibly unlikely, yes, but what if you do it millions of times a second over 3 billion years?

I fucking doubt it. You'd need more than just base pairs of nucleotides to start life. misread the post. Although, this does pretty much prove that it's possible for these nucleotides to be formed in space, and/or for them to be carried from planet to planet, which under VERY specific circumstances, may have allowed for the transfer of DNA between extraterrestrial organisms. However, base building blocks of DNA like the ones found in the meteorite form on 'dead' planets all the time, including earth 4,000 million years ago.

[Nadaka]

To clarify : this does not suggest extra terrestrial life AT ALL.
This only show that the raw material of DNA exist in space and may be imported.

An analogy would be that metallic Iron can be found in meteorites, the same that has been used for spear and arrow-point by the Inuit. That does not suggest that there are arrow point in meteorites.

You are not thinking like a sculptor. There are arrow points in the meteor. It is the artists job to remove the parts that are not arrow heads.

[MaximumZero]

More cool shit...IN SPACE!

Thin belt of antimatter found in Earth orbit

Not all that significant AFAIK, but still damned cool.

Is it bad of me that the first thing I thought of was attempting to harvest it for fuel?

[RedKing]

More cool shit...IN SPACE!

Thin belt of antimatter found in Earth orbit

Not all that significant AFAIK, but still damned cool.

Is it bad of me that the first thing I thought of was attempting to harvest it for fuel?

No, it makes you NASA material. 

Dr Bruno said that, aside from confirming theoretical work that had long predicted the existence of these antimatter bands, the particles could also prove to be a novel fuel source for future spacecraft - an idea explored in a report for Nasa's Institute for Advanced Concepts.

[kaijyuu]

Is there remotely enough of it to power a ship? Plus, antimatter-matter reactions do put off a lot of energy, but my understanding is converting that energy to propulsion is hard since the reaction just shoots out a bunch of gamma rays.

[MaximumZero]

So we use the gamma rays to push water over a waterwheel once, and back into the same pool, where it continues pushing the waterwheel forever! NASA + Dwarven Perpetual Motion Machine = Long distance space travel!

[MetalSlimeHunt]

Eh, after Miller-Urey I'm not very impressed by this. Come back when you've got some live cyanobacteria on a meteorite and we'll talk.

[Euld]

LIES.  Vicious lies.  Those pieces of DNA are actually Satan!  Don't give in to the deception! 

Kidding.  Really