RNA compound and vitamin B3 found in samples from near-Earth asteroid | Hacker News Reader

RNA compound and vitamin B3 found in samples from near-Earth asteroid

cnn.com

143 pointsschappim106 comments

They didn't detect RNA which would be extraordinary. What they detected is Uracil, one of the molecules that is found in RNA.

They didn't found any other nucleotides.

"Other DNA/RNA nucleobases were not positively identified in both the A0106 and C0107 samples. This does not necessarily exclude a possibility that those nucleobases are present in the Ryugu samples, but just they may be below the detection limit under the experimental conditions employed"

https://www.nature.com/articles/s41467-023-36904-3

For having RNA you need a molecule composed of roughly 200 nucleotides. If we find RNA, it would be very indicative of DNA, so of living beings very similar to us

> For having RNA you need a molecule composed of roughly 200 nucleotides.

miRNA are order of magnitude smaller.

That's after DICER/Drosha processes the pre-miRNA/pri-miRNA transcripts. The pre-miRNA/pri-miRNAs transcripts can be a magnitude equal to or greater than 200 nts.

I would guess that whatever organic molecule was on that asteroid, it died off from the intense radiation in space.

Organic doesn't necessarily imply living.

It actually does: "Organic: relating to or derived from living matter"

This is the difference between standard usage and jargon.

Chemists consider any covalent compound involving carbon that isn't only carbon to be "organic".

Normal usage is what you wrote.

Alternative but widespread usage is "agricultural products made without synthesized fertilizers and pesticides".

Oh, and business jargon uses organic to mean "natural market growth or internally developed capabilities", as opposed to buying the growth or capability.

And in military usage, organic means "a permanently assigned assisting unit", so that routine vehicle maintenance, for example, is handled by people who travel with the vehicle.

It's like astronomer talking about metals. By which they mean everything that's not hydrogen or helium.

To their credit, I remember something about basically every element ionizes to some extent in space, thus exhibiting the "sea of electrons" behavior characteristic of metals.

> like astronomer talking about metals

This is particular to stellar astrophysics. Astronomers studying asteroids maintain the conventional definition.

I've taken to using "organic-branded" for the agricultural products, since "organic" is essentially an FDA brand, with regulations for usage of the branding. Its also my personal rebellion against "organic" having a functional meaning of "magicalhealthygoodness" in some circles.

Yes, /originally/ 'Organic' meant from living matter. However, when it was discovered that urea could be synthesised in the lab, we realised that there was no real distinction between 'living' molecules and 'dead' ones ...

Nowadays, 'organic' refers to chemicals with a majority (?) carbon content. It gets a little tricky for things like diamond and graphene (both materials) or for compounds that have a lot of heteroatoms.

Oddly enough, another nucleotide base (adenine) is exactly 50:50 C:N and has been proved to be synthesised from just HCN. So is it 'half'organic' :)

As a (former) organic chemist, this is spot-on. "Organic" doesn't really have a strict definition, but it's not so much "majority carbon" as it is presence of a C-H and/or C-C bond. I personally don't consider diamond and graphite organic, but some do. Carbon disulfide and phosgene (COCl2) usually aren't regarded as organic. And as you mentioned, stuff with carbon and lots of carbon atoms is a grey area (looking at you, azidoazide azide, but not looking at it too hard, it might not like that).

https://en.wikipedia.org/wiki/Organic_compound

Organic compound simply means that there are carbon-hydrogen bonds or carbon-carbon bonds in a compound.

The view that this requires "life" was a legitimate theory back in 1800s and was disproved in the late 1820s. (See the wiki link for more details)

What kind of intense radiation is needed to kill a molecule of teflon?

> They didn't detect RNA which would be extraordinary.

Correct, and they don't say that. They found an RNA compound. Uracil, one of the molecules that is found in RNA.

Not sure of the purpose of this comment to regurgitate what's found in the article itself, which goes into greater detail.

As someone who reads the comments more than the articles, I always appreciate when this kind of clarification is in the comments. It's one of the best parts of HN.

I appreciate it too

Honestly, me too, to the point where I open the comments in tabs before visiting the articles. It may be biased, but seeing what the HN hivemind has to say about the topic is usually as valuable, and often more valuable, than the linked article itself.

There are also situations like this one where, while I find the headline interesting, I don't care enough to read through the whole link - so I'll check the comments for any significant additions or corrections or clarifications, and sometimes read the interesting discussions that occur, but won't even click through to the main link.

It might come down to a question of number of perspectives - the linked article is usually by a single person/group (or worse, a news org poorly interpreting the results of a group), while the HN comment section will be filled with a variety of people, often with domain specific knowledge and experience.

All that to say, HN is an interesting community, and I don't think there's a "wrong" way to interact with/be part of it (as long as you're being respectful etc.).

The point is that the headline is ambiguous.

RNA is a compound, and Uracil is also a compound. Thus you cannot tell from just the words "RNA compound" whether they mean a compound that is RNA or a compound that is part of RNA.

Most of us are laymen to the subject. Please people, feel free to continue regurgitating concise and understandable information.

Fittingly enough, mother birds regurgitate their otherwise indigestible food so that their young can digest it.

Yeah, even the title here (now) is "RNA compound" not RNA.

It was when I posted my comment.

not even a nucleotide- just a nucleobase. It's missing the ribose sugar so it can't form polymers.

If it had 200 nucleotides you'd know for sure it's a contamination. RNA isn't very stable (in our conditions, I have no idea how it does at 3 Kelvin, blasted with radiation for a million years...)

RNA can be stable if it's dry but DNA is much more stable. I can't see DNA surviving undamaged on the surface of an asteroid, but I could see: DNA getting somehow embedded in a rock agglomerate, then the rock gets ejected from a planet, lands on another planet whole, and then the rock breaks and now you have dna on another planet. With enough deep time, this could occur (possibly) but I can't see it as an effective method.

instead, better to take tardigrades, induce tun state, embed that in rock, and let that float around for a while. They have pretty much everything needed to survive including safe storage for DNA, DNA repair enzymes, redundant DNA, radiation-resistant exterior, etc.

> if we find RNA, it would be very indicative of DNA

Or evidence for the RNA world hypothesis [1].

[1] https://en.m.wikipedia.org/wiki/RNA_world

>“Since the Hayabusa2 spacecraft collected two samples directly from asteroid Ryugu and delivered them to Earth in sealed capsules, contamination can be ruled out.”

I seriously doubt that it could be "ruled out" just like that.

For one, the spacecraft (or the empty capsules) could have been pre-contaminated before their launch.

Second, the capsules could have been contaminated after arrival even if they were "sealed" (perhaps the seal had issues, or maybe it happened when they opened them, since one assumes they couldn't test still sealed capsules, they'd have to open them).

I wonder if there's a "control group": a tiny but identical container that goes through all the same steps. Nothing can ever be proof that it wasn't contaminated or a seal was broken on the real but not the control container, like, nothing will convince an Internet conspiracy theorist, but a control vessel and a handful such missions ought to prove beyond reasonable doubt that it wasn't contaminated from earth. I'm personally already willing to trust that they thought of (and controlled for) these things and more, since it's their job and we're just thinking out loud here.

I don't know how they do it but I always thought the best way would be to have the probe place them in glass ampules and seal them while still in space.

While we are probably really good programmers, surprisingly enough these “scientists” seem to know how to do their job without our guidance:

https://earth-planets-space.springeropen.com/articles/10.118...

Well played. I do find HN to be full of "expert" commentators on any subject matter even if they aren't ;) Remember David Levinson (Jeff Goldblum in Independence Day) figured out how to defeat the alien invaders by uploading a virus to the alien ship. He used MacOS 8! Wasn't it a modem parity issue (8N1) or some other such nonsense for a space-traveling, gravity-defying spaceship?

They can also always be too confident in having done their job perfectly - and they can be that with or without our guidance.

It’s pretty clear if you read the paper they are not confident they did their job perfectly, and have erected guard rails around everything to cap the maximal contamination and established tests for assessing the extent of contamination exploiting assuming there is going to be contamination.

I'd ask why techbro culture makes people like you so confident in areas outside your expertise, but I just answered my own question.

It would be a little weird for it to be contaminated with only uracil. Sure, if they found full RNA strands you'd start to think contamination was more likely, but what are the odds it was contaminated but with only uracil, especially considering how far they've gone to prevent contamination?

> For one, the spacecraft (or the empty capsules) could have been pre-contaminated before their launch.

I had a really interesting discussion with someone who oversaw decontamination protocols and preparations for various satellites, including the JWST. The protocols they use to prep satellites for these types of missions are beyond stringent, and the chemicals they use are exotic as all hell.

All this to say, contamination is absolutely possible, but there is so much insane behind the scenes work to control for it that it shouldn’t be thought of as something they might “just forget” or casually missed.

Remember the faster than light neutrinos that turned out to be a loose cable? I doubt they "just forgot", but being perfect is more difficult than making a mistake somewhere in the process. Before they publish I would hope they Quadruple checked for every source of possible contamination. Instead of saying we did it right so obviously nothing went wrong.

I think you're reading too much into the phrase "can be ruled out." I suspect that the leader author was saying "Contamination is possible, but based on our procedures, test methods, etc, the overwhelmingly larger probability is that we did detect <...> in the samples, and that the detection was not from pre- or post-contamination."

Could the paper's conclusions be incorrect? Yes, I think everyone--the authors included--will agree that "something could have gone wrong." But pointing out that "something could have gone wrong" is probably not a new idea to most readers.

I've talked to a few scientists in this area and I found out the Viking project life detection experiments generated a lot of controversey. https://www.nytimes.com/2021/08/04/science/space/gilbert-v-l...

Google [or search engine of your choice] is your friend.

https://earth-planets-space.springeropen.com/articles/10.118...

“Scientists have previously found nucleobases and vitamins in certain carbon-rich meteorites, but there was always the question of contamination by exposure to the Earth’s environment,” said lead study author Yasuhiro Oba, associate professor at Hokkaido University in Japan, in a statement. “Since the Hayabusa2 spacecraft collected two samples directly from asteroid Ryugu and delivered them to Earth in sealed capsules, contamination can be ruled out.”

In other words, there is a history of finding similar compounds on meteorites but under circumstances that made it iffy, at best, to assert these compounds came from space. In spite of debate in comments on HN, this sample constitutes stronger support than we previously had for the idea that these compounds really exist on meteorites in space.

The thing I was hoping to see in the comments is discussion around the complexity of these compounds and thus how likely they are to form abiotic.

Looking at vitamin b3, it seems very simple.

My take away is more that the chemistry of life as we know it is pretty prevalent and probably forms readily under many circumstances. I am not shocked this wasn’t an actual DNA strand. Even if someone left some DNA out on an asteroid over enough time I expect it would deteriorate. The universe just bombards stuff without an atmosphere too much for naked DNA to survive in those conditions.

This is basically the biggest success I could rationally hope for from this probe. Great work for those scientists and I am so amazed!

This has gotta add weight to the Panspermia hypothesis.

Panspermia is a hypothesis that suggests life on Earth may have originated from microorganisms or organic matter that traveled through space, potentially from other planets or moons in our solar system or even from other star systems.

> Panspermia is a hypothesis that suggests life on Earth may have originated from microorganisms

But where did the microorganisms on the asteroid come from?

home

Space Balls

If the creation (natural synthesis) of an organic molecule requires extraordinary conditions (some cosmic very rare & special place), AND, such stupendously rare precursors are catalysts of generation of more complex organic molecules (like RNA) in more common conditions (rare but equally distributed planets like Earth), then an ancient chance event somewhere out there is possibly the source of all potential DNA based life-forms via astroid seeding. The entire issue with DNA/RNA is how did these complex molecules naturally arise.

The opposite. If such compounds are common in asteroids absent life, then the rise of RNA/DNA on different planets is more likely to be happening spontaneously, without anything traveling between planets. This finding suggests that some building blocks of life may be very common, increasing the chances of life arising locally without need of panspermia.

Is that the opposite?

It's an alternative explanation, but I'm not sure if this is evidence against panspermia either.

Its isn't evidence against, but it is evidence that panspermia is less necessary than previously thought. Should we detect life out there somewhere, the fact that these compounds are more universal decreased the likelihood that that detected life is related to us through panspermia. The fact that life in two places uses RNA no longer means that it must be directly related to the RNA/DNA-based life on earth.

Way too early in the science needed to characterize as evidence for or against panspermia or much else. We need much much more work like this.

> too early in the science needed to characterize as evidence for or against panspermia or much else

Every organic compound that spontaneously develops under natural conditions is an argument against the necessity of panspermia.

Just to complete the circle:

The opposite would be Earth was hit by other objects in the distant past, and the collision blew large chunks of Earth into space. Complete with B3 and RNA. (Especially credible as the body in question is a near Earth asteroid.)

All the posited explanations are reasonable hypotheses in my opinion.

I don't think it gives more weight to panspermia.

Rather, IMHO, it gives us more information on how the conditions on Earth might have been when life emerged. We're getting more and more clues that a lot of the basic blocks of life are present in asteroids and thus might have been present on the primordial Earth as well in some watery soup where life emerged.

pseudo-panspermia, the blocks of life comes from space, but life emerges in a planet.

> the blocks of life comes from space, but life emerges in a planet.

This is the theory of panspermia. No pseudo prefix required.

Not quite. Panspermia says that life exists on other planets and then somehow is distributed through space to other planets. The OP was just saying that the "building blocks" exist throughout space but life develops on planets.

Edit: The wikipedia article breaks it down sufficiently, https://en.wikipedia.org/wiki/Panspermia

That’s a cope, not an explanation. It’s like saying “God made the world”. It doesn’t answer the question because then the question is who made God.

If your theory relies on external creation on another planet or whatever, then it’s meaningless because how did life start there. If life could start there then it could have started here so why do we need your theory at all?

ASTEROIDS!

Crunchy rocks of breakfast cereal from the depths of space!

Delicious with cold milk.

Fortified with RNA compound and vitamin B3.

No added complex organic molecules.

I just want Asteroid that tastes like real Asteroid!

Yes. Don't fall for the propaganda. It is all Big Asteroid!!!

"The Japanese Aerospace Exploration Agency mission collected one sample from the asteroid’s surface in February 2019, then fired a copper 'bullet' into the asteroid to create a 33-foot (10-meter) wide impact crater."

10 meters seems like a pretty impressive crater for a science payload launched from a deep space probe. In case anyone else is curious, there's a detailed writeup[1] about the Small Carry-on Impactor (SCI) that was used.

It looks a little bit like a swords-into-plowshares version of a HEAT warhead. A shaped plastic explosive charge simultaneously launched and deformed a copper plate so that by the time it hit the asteroid, the projectile was shaped like a hollow bullet. ~2kg moving at ~2km/sec, so about 4 million Joules, or about 200 times the kinetic energy of a .50 BMG round. That's some bullet!

[1] https://www.planetary.org/articles/what-to-expect-hayabusa2-...

Given infinite time you would expect any pool of materials to eventually wibble together into certain compounds. Those compounds will wibble infinitely until they create structures. Some of those structures will be able to wibble compounds together. Some of those structures will be an exact copy of the structure that made it. Those structures will then replicate.

Simple life seems inevitable. It’s the tiers above that are the hard part. We only have mitochondria because we ate them and forced them to reproduce inside of us. Without that we would probably have never got beyond the single cell level. There’s a lot of random developments that we could have missed and ended up as just slime on a rock for eternity.

I wonder if this supports the RNA World life origin hypothesis https://en.m.wikipedia.org/wiki/RNA_world , because Uracil doesn't occur in DNA.

It's my understanding that the RNA world hypothesis is pretty much widely accepted these days anyway. The open question is more how you get to the RNA world in the first place. The RNA hypothesis as such is more an hypothesis of what preceded life based on DNA and protein, and less so a theory of the origin of life from non-life per se.

The two main camps today seem to be "metabolism first" with people like Nick Lane and "genetics first" with people like Jack Szostack.

I used to favour the genetics side but I've been leaning more towards metabolism recently. Lane's research on this has been fascinating.

Can you link to this research? Perhaps an overview link would make a good OP for Hacker News.

He provides download links to most his papers on his website:

https://nick-lane.net/publications/

As for a good introduction to what his(and the many other people working in his lab) research is getting at, I really recommend the podcast episode he did on Sean Carroll's Mindscape podcast.

RNA is a structure capable of being both a store of data and a catalyst.

As RNA forms spontaneously with time, eventually you would end up with an RNA which can catalyse its own ingredients and replicate. As soon as you have one, it would replicate and take over the pool. Random changes would then lead to advancement.

Membranes also form spontaneously so the replicating RNA could find itself a bubble through random chance and live in it.

I read Hoyle and Wikiramasingh's books back in the late 70s and 80s. Fun reads and thought-provoking no matter what side you fall on the Panspermia argument. To those who downplay it as not really being RNA, this is one mission to a near-Earth asteroid. What are the odds you would even find a nucleobase? Amazing work and the contamination argument is always presented in light of any such discoveries. There was also the dismissal of fossil-like impressions in meteorites cut open as just looking like a known life form. I WANT TO BELIEVE ;)

It's interesting to think of space rocks like asteroids in the manner of pollen, or pollination in how organic molecules spread around in the solar system. :D https://gardens.si.edu/gardens/pollinator-garden/why-what-wh....

Not just the solar system: https://en.wikipedia.org/wiki/Panspermia

of course I meant the universe, but cool didn't know that term.

not only uracil and niacin, also other molecules:

'''revealing that a wide range of organic compounds such as racemic non-protein type amino acids, alkylamines, carboxylic acids, polycyclic aromatic hydrocarbons (PAHs), and nitrogen heterocyclic molecules are present in the aqueous or organic extracts'''

from the linked paper.

racemic mix refers to the equal amout of stereoisomers

For the people that say there are not extraterrestrial life, we are literally “extraterrestrial” life.

> RNA compound and vitamin B3 found in samples from near-Earth asteroid

They can start mining asteroids for vitamins. /s

Perhaps we even find B12 resources so we might not have to eat meat anymore /s

Where do you think vitamins come from ? Haven't you seen Star Wars ? (Millenium falcon lands inside an asteroid and the heroes are almost eaten by a space "dinosaur" living inside the asteroid) /s

This is a good idea! I've heard the asteroids are the source of many meaty ores.

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