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Comment by NathanKP | Hacker News Reader

One question I had about the Tesla launch that wasn't clear is whether the car was thoroughly sanitized prior to sending it up. My understanding is that any object that has the potential to reach another planet has to be thoroughly sterilized to avoid inadvertently introducing Earth organisms to another planet. The chances are technically low but it is theoretically possible and its why NASA has a dedicated page on "planetary protection": https://mars.nasa.gov/msl/mission/technology/insituexplorati...

My hope is that the SpaceX people did the same for this Tesla. Otherwise it would be rather reckless especially since now it is clear there wasn't a specific controlled orbit path, just a burn to launch it as far as possible, and now its possible it could end up impacting something and potentially contaminating it with Earth organisms.

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NASA doesn’t sterilizes most probes either even planatery ones unless they are destined to land in a protected environment.

Cassini was deorbited on Saturn specifically to minimize the chances of it crashing into one of its moons and contaminating it.

If the car would land on Mars it would be a whole other story but as long as the biggest risk is that it would burn in its atmosphere if it even stood a chance of being captured it doesn’t need any extraordinary sanitation other than the usual clean room treatment.

Mars does not have enough atmosphere to assure space craft burn up completely. Once it is in orbit there is good chance it will reach ground.

Mars has sufficient atmosphere to burn that car into a crisp considering the speed it’s going at, it’s not like it will slow down and park it self in Martian orbit neither do most probes which is why they come with a heatshield so they won’t burn up during aerobraking.

The heatshields are necessary so that the payload is stable aerodynamically and so that it isn't burned to crisp.

But the atmosphere is very thin so that it is currently major challenge to use it to slow anything down before it slams the ground.

While the temperature is governed by the speed of reentry (large speed relative to atmosphere molecules == high temperature) the heat transfer is depending also on the pressure. Low pressure == lower efficiency of heat transfer. Martian surface is around 600Pa, only 0.6% of Earth surface pressure.

This means, that entire Mars reentry profile is comparable to reentering just 0.6% of Earth atmosphere mass. This happens at around 40km (25miles) on Earth. It means, that if it is able to reach 40km above surface of Earth it is as if it already crossed entire Mars atmosphere.

It is also worth noting that the altitude of peak heating depends heavily on angle of reentry. In a steep reentry the period of peak heating happens much lower. For example, the peak heating for Space Shuttle was at about 70km, but that was only because the profile was kept purposefully extremely shallow to be done with heating before it reaches dense atmosphere.

You be the judge if it is enough to completely burn up Tesla Roadster, I find it difficult to reach any scientific study of Tesla Roadsters being thrown into Mars gravity well to watch results.

Andy Weir, the author of The Martian, had this to say on sterilization of Mars probes:

WEIR: I am not a fan. And I’ve mentioned this a few times in the past.

My main concern is this. OK, so just run through a little flowchart in your mind. Start off by saying, “Is there anything that’s on Earth, any organism on Earth, that can survive an eight-month journey through the vacuum of space and the radiation of space, and all the other rigors of being just out in space, that can survive the trip from Earth to Mars?” OK, maybe some tardigrades could; it’s possible; maybe some bacteria inside of something could. OK.

But if your answer to that is no, then there’s no need for planetary protection.

If your answer is yes, then the next question is, “Is there any life native to Earth that could find anything to eat on Mars?” That there’s any, anything . . . “Would it be able to survive and reproduce on Mars?” I don’t think it would. So if the answer to that is no, then there’s no need for planetary protection.

If it’s yes, then ask yourself this: “Would that life that you accidentally introduced to Mars — ” Oh, sorry. Right at the top of this flowchart, ask, “Do you think there’s life on Mars?” If the answer is no, there’s no need for planetary protection. If the answer is yes, then move into these other steps.

Now, so since we’re assuming there’s life on Mars, move ahead to, “Would the Earth life somehow be more adept at surviving on Mars than naturally evolved Mars life to the point that it would displace it and ruin the Mars ecosphere?” Seems very unlikely to me, so I would say no.

But if your answer to that is yes, then ask yourself if the Soviets properly sterilize their probes.

The FAA people in charge of issuing launch licenses worry about this kind of thing -- and commented a while ago that they'd lean heavily on the NASA Planetary Protection Officer for cases like this.

http://www.thespacereview.com/article/3260/1

> “We don’t have the expertise in-house when it comes to planetary protection,” said Kelvin Coleman, acting deputy associate administrator for commercial space transportation at the FAA. His office licenses commercial launches, a process that includes a payload review that would, potentially, include a planetary protection review. He said the FAA would “be leaning on” NASA to provide planetary protection expertise.

I always worry more about the risk that earth contains the only occurance of life in the universe and if something destroys earth then all life is destroyed forever.

But sure, protect your planets ...

"the risk that earth contains the only occurance of life in the universe"

That seems almost impossibly unlikely considering the size of the universe. The number of Earth-like planets capable of supporting life is thought to exceed the number of grains of sand on our planet. Surely life will have evolved on at least a few of them!

True but no one knows how likely life is to start up from raw materials in the first place.

It would also need to reach a balance with its planet and not simply eat up all the resources and die out.

> It would also need to reach a balance with its planet and not simply eat up all the resources and die out.

Like we're kinda doing?

Humans are far from dying out and incredibly resilient. Things like climate change are not really about the human race surviving, more the scale and quality at which we continue to live. Both important but very different things.

I was speaking more to the resource utilization part of the statement, but sure: technically, there will probably still be humans left, in places, if we keep going at the rate we are.

If we're (as a species) lucky, that number might even exceed the minimum viable population.

The individuals in that circumstance probably won't feel very lucky, though.

Familiarize yourself with the Fermi Paradox. http://fermisparadox.com/

The Fermi Paradox deals with intelligent life (aliens) capable of being detected by other intelligent life (us). Life itself, however simple, is likely extremely abundant - there is even some inconclusive evidence that life once existed on Mars.

The fact of intellegent life arising somewhere else in the universe is statistically guaranteed. However, the sheer physical vastness of space and the timeframes that an intelligent species may be solvent mean that two separate intelligent species arising next to each other at the same time is almost a statitical impossibility. What the fermi paradox strongly supports is that faster than light/deep space travel in our little corner of the universe has not been figured out yet.

> The fact of intellegent life arising somewhere else in the universe is statistically guaranteed.

We have insufficient data from which to make that conclusion to any reasonable degree of certainty.

We also have an insufficient definition of “intelligent life” to even enable gathering such data.

I once saw a paper that calculated the probability distribution for the number of planets with intelligent life, using estimates from other papers and the best data currently available. IIRC, the conclusion was that it's likely that we're alone in the galaxy, and not that unlikely that we're alone in the universe.

IIRC, many low-probability events were in the development of simple life, so life itself might be surprisingly thin too.

Do you have a link to this paper?

Life got going on Earth very early on, now perhaps it was a lucky fluke, but it happened early.

When you consider that there are perhaps 100 Billion stars in a typical galaxy, and in the observable universe there are perhaps 200 billion to 2 trillion galaxies, for me personally, I can only conclude that the universe is teeming with life.

Lets say Earth was a 1 in a million, that still means there are perhaps 1000 planets in our galaxy which contain life. Now if you multiply that by the number of galaxies you end up with billions.

Now intelligent life is a whole different beast, it could be that within a single galaxy civilisations come and go at different periods and never exist at the same time. Civilisations which are in different galaxies will find it extremely hard to contact each other.

Could it be this talk? http://www.jodrellbank.manchester.ac.uk/media/eps/jodrell-ba...

That looks like it.

Well, sure, on a few of them. And then what? Could be quite a leap for single-celled organisms to evolve into something resembling a flying insect. Given how successful insects have been on our planet, why would life evolve into anything more complex?

I'm actually not too worried that we're the only example of life in the universe. Instead I'm more worried that the galaxy is filled with planets containing nothing but slime mold.

It would be pretty trippy to think about. A planet not unlike our own in terms of atmosphere, water content, temperature, etc, and it's all slime mold. Entire mountains, covered in mold. Rolling hills of mold. Valleys thick with mold. Mold everywhere.

Ours may very well be the only planet in the universe where life evolved to one day ponder the possibility of a universe filled with mold. Multiverses and Moldyverses.

So, who knows, we may take it upon ourselves to spread life and make the universe less moldy.

Insects are actually very eolutionarily complex if you think about it. It’s much more logical for a single celled organism to develop say a membrane than a carapace. Especially since single celleds start in an ocean to our knowledge.

I am more worried that humans are destroying this planet and ecosystem at an exponential rate, no external cause needed.

https://www.theguardian.com/environment/2014/sep/29/earth-lo...

> The number of Earth-like planets capable of supporting life is thought to exceed the number of grains of sand on our planet.

I believe the popular statement is more towards 'There are more stars in the universe than grains of sand on all beaches of earth.'

Once you bring in inland sand deposits etc this would probably not be true given the estimate (I've read but there must be other) of stars to beach sand grains is fairly close given the scope.

And as for planets, I'm not sure the ratio of 'earth like' planets to star ratio in the universe but would suspect this to be less than 1:1 given in the milky way this averages a less than 2 earth like planets for every 10 stars.

It's such a great analogy. Its the closest as I can come to understanding the scale of the universe we live in.

Somone had to be first. Why not us.

"And millions of years later, after the Earth had long since gone quiet, the strange metal object swung closer to the red planet.

After all these years, passing the red planet so many times, it had caught enough wisps of gas from its atmosphere that it was going to finally come to rest — finally land there at last.

If landing is what you want to call it.

Down the machine came. It arced across the sky — slowing much more quickly now. And as it slowed it fell closer to the surface still, and got hotter and slower still...

When it finally hit the dunes of this world it scattered into all of its components. For miles and miles so many small metal and plastic parts from Earth flew and tumbled. And also, some stowaways.

What stowaways? Why, little organized corpuscles of organic chemicals. They were plentiful at one time on their home planet of Earth. But now, millions of years later, they found they had been travelers to a strange, new world.

Let there be life!"

Poorly channeling "The Last Question" in a way....

There's risk management involved.

Sanitizing is considered when you're planning a planet landing. Space is big, so on the timescales of human civilization, the probability of actually hitting a planet by accident is negligible. If that Roadster lands on Mars in a hundred million years, we won't care.

If that roadster hits Mars and seeds Mars, that would be huge and interesting for science. Mostly because "How did something survive in space for that long?"

True, but by that time it won't be our science, it will be descendants-of-our-dolphins' science. Or aliens-from-outer-space science.

Seriously, the only way I can see humanity not getting to Mars before the Roadster is if we completely fail as a species.

Also "how did a plastic car survive reentry?"

SpaceX did do the analysis for NASA to show it had an exceedingly small chance of contamination.

Awesome. That's great to hear. I was specifically wondering since this isn't just a metal satellite, there are cushions and fabric and stuff which can probably hold a lot of microbes.

You'd be surprised what even metal spacecraft contain. Not everything sent into deep space is sterilized, and even stuff sent to Mars contain a number of actual spores.

To be clear, they analyzed the likelihood that the Roadster would hit a planet (exceedingly small), not the likelihood that the Roadster is carrying biological life from Earth (which is exceedingly high).

Though the odds of that life surviving for extended periods of time in space is close to nil.

Errrrrrr:

http://www.esa.int/Our_Activities/Human_Spaceflight/Research...

We have very different definitions of extended periods of time. Elon's talking about it orbiting for millions of years. It's definitely not going to hit anything anytime soon.

He also completely missed the intended orbit so you can't use that "millions of years" number as evidence that it will not hit something.

That is still a good bet to make, it's very hard to hit anything even if you spent considerable effort specifically trying to. Also, there wasn't an intended orbit as much as there was a general direction and an "empty the tank" burn.

Yeah I saw that in another comment further down the chain. With all the hype around the Mars shot I assumed the ability to accurately place the car in orbit was a worthwhile goal. Not being a rocket scientist I wasn't aware that just knowing how far the thing can go is equally (or more?) interesting.

>its possible it could end up impacting something and potentially contaminating it with Earth organisms.

I dunno about you, but I would be really, really excited if other planets became infested with Earth organisms. I mean, that's kinda the whole reason for space travel in the first place!

I understand the argument for sterilized launches, etc. etc. but I can't help but wonder if it's holding terraforming back in the long run.

I bet the technologies required for teraforming a planet will hold back teraforming more than a concern for spreading microbes.

Naturally Star Trek style terraforming is off in the far future (if at all), but I wonder if we're not too far away already from some more humble projects...

A genetically modified lichen, or fungus, that was designed as a stepping stone towards a better Martian biome, and a launch setup to seed them effectively isn't too far outside the bounds of present day work with genetics, and present day launch & deployment systems.

It's far less sexy, but a multi-generation approach to terraforming could yield a usable Mars without too much magic...

NASA is only trying to keep Mars sterile for 100 years or so, probably doesn't matter much on the scale of terraforming

Well for those of us who live less than 100 years it matters a whole lot.

Understanding if any organisms can appear, evolve, be brought by asteroids and survive Mars conditions is probably even more important for terraforming than polluting the experiment with Earth's lifeforms.

Actually, the real risk is that, by entering in contact with Earth biology, some forms of life incorporate them and develop in a toxic way.

The closest equivalent is inter-species infections, like the Avian or the Porcine flus. Having humans near unhealthy ducks or pigs constantly means mutated strains have a higher chance of carrying dangerous behaviour from one species to another.

There are a lot more to say around bio-chemistry basins, carbon-based vs silicon-based (or another compound) — but the idea is not exclusively to protect life there.

Two simple reasons:

1. If there is life elsewhere, we want to make sure terrestrial lifeforms don't drive it to extinction before we get to see it. 2. We want to make sure that if life is found elsewhere that it isn't due to our own contamination of the site.

That's what I always thought as well!

>I dunno about you, but I would be really, really excited if other planets became infested with Earth organisms.

http://reducing-suffering.org/applied-welfare-biology-wild-a...

https://foundational-research.org/the-importance-of-wild-ani...

http://reducing-suffering.org/will-space-colonization-multip...

What is almost always ignored is that these animals would have feelings, and many would suffer enormously as a result of being created into Darwinian ecosystems in which predation, disease, and premature death are endemic. Theologians ask why a good God would create so much cruelty in nature. Future humans should likewise ponder whether it's morally acceptable to create new ecosystems containing vast amounts of suffering, or whether they should pause and seek more compassionate alternatives if they embark upon space colonization.

You are projecting human morality to natural processes.

Viruses and bacteria don't have feelings and the vast majority of the biomass on Earth is not even capable of suffering.

I've heard a few times today how radiation will peel the paint off the car. Shouldn't that also sanitize it pretty thoroughly?

You could be surprise how resilient are the microbes against the harsh conditions of space.

Yep these things can actually survive in the vacuum of space as well as go without food or water for 30 years: https://en.wikipedia.org/wiki/Tardigrade

For other readers: yes the Tardigrade is likely to be resistant to the extreme radiation of the Mars-Earth voyage.

They'll be surfing the mycelial network before we know it :/

Yeah, but you're not going to find those in the stitching of a leather Tesla Roadster seat.

Some bacteria can survive very high levels of radiation. For example: https://en.wikipedia.org/wiki/Deinococcus_radiodurans

There's enough places for microbes to hide from radiation. On that short of a mission it wouldn't be surprising to see microbes. There are various microbes that can withstand the nominal radiation there. Would be much harder to survive the Van Allen belts and CMEs, but it is possible. If we were talking about a 100 year mission, that would be more surprising. Even hardy microbes don't like extended stays in vacuums and have to go into a hibernation state. There are bacteria that can survive for decades in a vacuum and low temperatures.

Disclaimer: not a biologist

>On that short of a mission

how short? because i thought the timeline we're talking about is that the Roadster is not going to run into any planet for as long as they've run simulations for, but it's theoretically possible that it might, at some point, hit something.

I would imagine that the lack of any kind of food source for bacteria, freezing cold temperatures, and space radiation should be enough to sanitize the vehicle from anything from earth. We're not talking about organisms that thrive at the depths of the ocean or tardigrades (although I'm sure someone will bring them up). We're talking about molds and bacterias that grow in warm, damp places like car seats and dirty human crevices. I would be surprised if they lasted out there and would be giddy if it survived long enough to grow further. That's an experiment, right there.

depends on the destination / trajectory of the object. This object has almost zero chance of ever hitting anything, so it doesn't have to go through the super crazy sanitizing that the Curiosity rover did.

That was probably true of the original trajectory, but now it's supposed to fly quite close to Ceres and scientists want updated data to see if a collision is likely.

“Quite close” is relative, given how ridiculously vast space is. The chances that they fire blindly out into space and just happen to hit Ceres seems so unlikely as to be basically impossible.

True, but it's not like you have to hit an object head on, but merely pass within it's gravitational field which is far bigger.

Pass within its gravitational field at a slow enough relative speed for capture. Remains exceeeeeeedingly unlikely.

Nonetheless people are asking SpaceX for data to calculate the probability because they seem to think it's higher than 0 because of the unplanned trajectory.

It will not cross Ceres orbit.

The pale blue dot image gives some sense of scale here. Is it in the orbital plane of Ceres? I too would be interested in seeing the data results. If it's not orbiting on same plane then risks of collision drops further it would seem - would involve a plane intersection at the exact distance from sun Ceres orbit is at same time Ceres is there.

Of course as a practical matter, NASA can deny the use of their facilities to whomever they choose.

If SpaceX had their own launch facility, etc., are there legal restraints from contaminating another planet (possibly purposefully)? And if there are such restraints, what is their legal justification?

Need an FAA license to launch, the US is signatory to various space treaties, etc.

None of which say anything about planetary contamination. GP is right that there is absolutely no laws enforcing “planetary protection” on commercial entities (thankfully).

Do they not?

UNOOSA, Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, Art. IX [1]:

"States Parties to the Treaty shall pursue studies of outer space, including the Moon and other celestial bodies, and conduct exploration of them so as to avoid their harmful contamination..."

Note that State parties are responsible for the actions of their nationals later in the paragraph.

Is the above wrong? I admit to not being a space person.

Edit: [1] http://www.unoosa.org/pdf/publications/STSPACE11E.pdf

Wow that is selective quoting. The law is “harmful contamination of the Earth”. Nice use of “...” there. That text is only about bringing stuff back to earth.

No it isn't. The text refers to "the Moon and other celestial bodies." See for yourself: http://www.unoosa.org/pdf/gares/ARES_21_2222E.pdf

Read your link again. That sentence, the only one which says harmful contamination, refers to the earth, And only the earth. It is very explicit about that. I don’t know what else to say.

Not to wade into your fight, but danaliv is right. Here is (most of) the sentence:

“States Parties to the Treaty shall pursue studies of outer space, including the Moon and other celestial bodies, and conduct exploration of them so as to avoid their harmful contamination and also adverse changes in the environment of the Earth resulting from the introduction of extraterrestrial matter....”

The “their harmful contamination” part clearly refers to something plural (the moon and other celestial bodies). The second part would be redundant if those were sources, rather than recipients of contaimination.

The FAA license process includes an interagency consultation, which specifically allows NASA, DOD, State, etc. to weigh in.

Yeah but NASA doesn’t get to just say no out of spite or anything, which legaly speaking is what a planetary protection objection would be. There is no statute they can point to that says commercial entities can’t litter the solar system with microbes if they want.

Article IX of the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies reads in part (emphasis added):

"State Parties to the Treaty shall pursue studies of outer space, including the Moon and other celestial bodies, and conduct exploration of them so as to avoid their harmful contamination and also adverse changes in the environment of the Earth resulting from the introduction of extraterrestrial matter and, where necessary, shall adopt appropriate measures for this purpose."

Sure, they wrote that. But once you're out there, what treaties apply? Nobody exerts hegemony over the Moon. Its all hot air.

This conversation is about whether NASA would object to an FAA-issued launch license on the basis of potential contamination, not whether there are police on the moon.

Right; NASA would have to decide to observe some unenforceable treaty. They also have to decide whether to launch on national leprechaun day or not. I'm not sure why either is an issue NASA would step up to try and enforce.

There's a National Leprechaun Day? How comes I missed that memo?

I look forward to Liberia moving into the spaceport business:

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

It is shipping, in a different dimension.

Obviously those booster rockets might get a bit tired after doing daily commuter flights for a decade or so, therefore there will also come a time when a third world country, e.g. Bangladesh becomes the place where old booster rockets go to be scrapped, so, next to the ships on the beach booster rockets crash down and small children working with no health and safety tear them to pieces.

They never were going to send it to mars. The plan was to send it out to a orbit that could reach mars if they pointed it correctly.

Now that they know its final orbit they can compute if it will hit anything for thousands/millions of years and slightly adjust it if it does.

There's no capability to adjust the trajectory at this point.

I think he means adjust their calculated trajectory once the collision occurs.

They've sent one vehicle, I suppose they could send up a tow truck to repossess it...

There is also the fire extinguisher in the passenger foot-well, spaceman can just use that to correct his course and get to Mars, maybe to wait for the tow truck there...

After the burn was complete they can use the cold gas thrusters to slightly change the orbit (a few mm/s now adds up over hundreds of years)

I heard the batteries were only good for 12 hours. You'd need some sort of power to fire gold gas thrusters.

The final burn was about 6hrs in, so plenty of time then to do any terminal maneuvers (simulating thousands of years shouldn’t take more than an hour)

I think the people behind this launch would have given some thought to this. I mean they're quite thorough and intelligent people. As in so clever and interested in the subject that they could be ..... Rocket scientists... :P

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

> Tersicoccus phoenicis is a member of the bacterial family Micrococcaceae. It has only been found in two spacecraft assembly clean room facilities and is resistant to the methods normally used to clean such facilities. The species name is derived from tersi, Latin for clean; coccus, Greek for berry; and phoenicis, from NASA's Phoenix lander, the spacecraft being prepared when these bacteria were first discovered.

Even if it was sanitized is it worth it to have a car exploding on one of our celestial neighbors?

It's funny and cool to see a car in space as long as we're not hurtling garbage into other planets.

This isnt a real concern... right? Like... of all of the things to worry about in a rocket launch.

Very real concern. A lot of effort goes into sterilising craft intended to land on or impact other planets. If we fail to do so, we run a real risk of seeding earth life on those planets and forever ruining our chances to test them for the existence of life prior to contamination.

Not everyone sees that as a problem.

While not everyone likely sees seeding Earth life on another planet as a problem, I think most would want to know if life existed there prior to that, since it helps us answer quite a few fundamental problems.

Name one “fundamental” problem it would answer.

I'm not sure why I used "problems". It's obvious to me I meant "questions", so likely I just misspoke. Knowing if life exists elsewhere at at certain minimal levels answers some fundamental questions.

The prioneers and experts of the field see it as a problem. The uninformed opinion of the general public doesn't carry much weight on this matter.

People who don't see it as a problem should take the time to read one of dozens published papers outlining the dangers and problems it will pose. If they then still don't feel it's a problem, they're encouraged to publish their own research supporting that view.

That is not true. Many people, including 'pioneers and experts' think that we are going to far in how big of a deal we are making this out to be.

We can not do this forever if we want a real human outpost there.

Some do and some don't. In terms of knowing about life on other planets of course it would be ideal to maintain planetary quarantine protocols and so on. The problem for exobiologists is that given the absence of visible life in our local system, any life that does exist is fossilized or fragile, and of course we would want to approach it with the same delicacy that we would any other fragile thing.

On the other hand, our solar system is but one among many and the longer we hesitate in exploring this one the longer it will be before we are able to explore others. TAn excess of caution can become an excuse for inaction. If earth is an oasis in a planetary desert, the way to find other life is not by maintaining extreme caution about disturbing the surrounding sand dunes but by trekking across them in search of other oases.

It certainly is: https://planetaryprotection.nasa.gov/

Yes, but only if you're purposefully aiming at a planet.

It's a big deal. This is essentially our equivalent of the prime directive.

It would likely burn up on the entry, it’s still got air friction in Mars atmosphere

I don't see the problem of introducing organisms to other planets.

Here's one: when you get there and are looking for extra-terrestrial life, you won't know if the things you find are native, or if they got there on their own somehow, or if you brought them with you. Maybe you don't care, but I think that knowing the answer to that question would be super interesting.

You still wouldn't know, would you?

Having a self sufficient human settlement on Mars would also be super interesting, and vital to reducing existential risk. You have to pick one.

>You have to pick one.

Why? Why can't you have both? Once we verify that there isn't measurable life on Mars, we can start a human settlement.

Even if there is life on Mars, we can consciously decide to build a colony that may wipe out that life, after we studied it.

It would, but there's a bunch of other celestial bodies that offer at least as much potential, eg Europa. I share your interest, but not to degree of stopping all other activity while you indulge your curiosity, because other people would like to go and explore directly. I'm not saying just ignore the issue and barrel ahead, but would-be exobiologists should make ambitious and timely proposals of what they intend to sample, what they expect to find, and how long they need to check, in order to give other people a chance to pursue their interests.

From the link I sent:

> The United States is a signatory to an international treaty that stipulates that exploration must be conducted in a manner that avoids of the transportation of living organisms to celestial bodies.

First of all the US is part of a treaty, so if we do introduce organisms to other plants we are violating the treaty.

> We wouldn't want to go to Mars and "discover" life - only to figure out later that we brought it with us! Scientists also want to study the planet and any life that might be there in its original "pristine state."

Ultimately I guess it comes down to why you are sending something to space. If your goal is science then contaminating the planetary environment with organisms is not great. If your goal is colonization (which I guess is SpaceX goal) then you probably wouldn't care. But I still think it's something that should be considered.

It definitely will be considered when they'll be actually aiming at Mars.

Aren’t humans half microbe by percentage of cells? Once we send someone on a one way trip it’s over.

Hopefully we don’t intend to keep this treaty forever, or we’ll always be stuck on this one rock.

The link is wrong. I work in this space and I know of no such international law regarding biological contamination, unless they are grossly misinterpreting the outer space treaty way beyond what it says and the context in which it is written.

Could you comment on https://news.ycombinator.com/item?id=16325757, did they err?

It’s totally misquoted. The line is “harmful contamination of the Earth” and the concern was about Apollo bringing back samples and the US taking proper quarantine safeguards ON EARTH.

Good to know. I wasn’t trying to sound fatalistic. Just pointing out it’s unworkable if true.

There's no scenario where human beings can land on Mars without biologically contaminating it. This is a powerful argument against human exploration of that planet. This is why God made robots.

There are worse places to be stuck than Earth. The food here is good!

What's wrong with introducing biological material to mars? I am so confused as to the rational here. Is it just so some scientists can get the glory of saying the discovered life on Mars and we're sure it's not from earth? What is the practical value of that anyway except some scientist's vanity?

>What is the practical value of that anyway except some scientist's vanity?

Proof of extraterrestrial life would be one of the greatest discoveries of all time with profound philosophical implications.

Yes, but there are two ways to approach that: cautiously explore apparently barren planets and eventually, maybe, find evidence of primitive life life, either ongoing or ancient; or explore as widely and as prolifically as possible.

I don't think it matters. If it's genetically interesting, that will increase our understanding of biology, but otherwise the practical implications are nil. Profound philosophical implications are a joke. You and the rest of the world would forget about it in a week.

Look at the UFO videos the pentagon released in December. No one cares.

> Look at the UFO videos the pentagon released in December. No one cares.

Because they don't prove that extraterrestrial life exists?

The practical value is that if there is uncontaminated life on Mars, scientists will be able to study it and hopefully open up new avenues of scientific inquiry. It's a research question and one that likely would contribute immense value if realized.

Specifically, it might teach us things about the prevalence of extromophiles, which promises to open up the universe to us.

Either we use extremophiles to establish beachheads in otherwise uninhabitable places, or we adapt ourselves or other beneficial organisms with the information we learn.

For instance proteins that protect against high or low temperatures.

Less speculatively, krill can be fed to things we already eat, and some krill survive on a diet entirely comprised of extremophiles.

Discovery of extraterrestrial life would have huge scientific and practical consequences. The rationale behind not needlessly contaminating other planets it to not make related science more difficult than it already is. It's not meant to hold forever, though - eventually practical interests will outweigh scientific benefits of keeping things pristine, and people will get the green light.

The opposite. If there is evidence of life on Mars, even microbial life, we'd potentially be contaminating that life and, if it didn't kill it, it might create strains of bacteria that are resistant to anything on Earth. If that ever made its way back to Earth, it might kill a large chunk of the population. We literally have no idea what the consequences of life and growth in those conditions are.

The detailed study of alien biology may provide insight useful for some practical application. Any specifics are wild speculation. Maybe we can produce an artificial pancreas that performs the function without registering as foreign to the immune system.

A an argument in similar vein for human exploration of Mars is that it's cool as fuck. The same way people enjoy food, many people believe they'll profoundly enjoy space exploration.

Are we assumed to have contaminated the Moon?

We are, and there is even some supporting evidence [1]. The evidence is not quite conclusive, however.

[1] https://en.wikipedia.org/wiki/Reports_of_Streptococcus_mitis...

Could infect the native population on the planet

I think before you ask a question like this, you should estimate the likelihood of something like this happening or ask someone for help on how to do that.

These sorts of questions are so boring, so easy to ask, and instantly derail the discussion.

Of course its low, but its still something that needs to be considered as more and more commercial organizations gain the ability to launch things into our solar system. Obviously an organization like SpaceX has a commercial focus rather than a scientific one like NASA. The more stuff gets launched by more people the more likely of contamination from something.

Between SpaceX, Blue Origin or any other space travel initiatives that end up succeeding we are going to end up with a lot more stuff in space which isn't necessarily going to be friendly to scientific efforts as in the past.

None of what you said conflicts with my comment and suggested question re-formulation.

The world is filled with an unlimited number of concerns about infinitesimal risk. Your question remains boring and distracting, and, as pointed out elsewhere, the risk is not likely enough to be important.

And yet, it is a very important question that people will always ask first. Exactly how low are the probabilities? This was a major concern with the bankruptcy of Iridium that concerned the President. The insurers at the time wouldn't touch it. And bad things happen:

https://en.wikipedia.org/wiki/2009_satellite_collision

https://en.wikipedia.org/wiki/Kosmos_954

Outer space is orders of magnitude larger than specific Earth orbit bands. The concerns you mention don't apply there.

That's true. My point was that interplanetary contamination is a concern that needs to be addressed, even if the probabilities are low. If nothing else, since it is one of the first questions that is going to get asked, including by the USG.

This is why I suggest that the question should be "what are the chances of a collision?" not "what has SpaceX done to mitigate this?" since the former question admits that the asker does not have the background to assess anything, while the later suggests SpaceX has done something wrong if they haven't taken concrete actions.

As it turns out, the difference in probability between the things you mention and interplanetary collisions is astronomical -- like dozens or more orders of magnitude -- and a minute of Googling shows that NASA frequently satisfies the planetary protection rules by ensuring that non-sanitized parts of inbound spacecraft miss the planet on the first pass (even though they will in principle be circling in the same general orbit for a billion years).

Lots of boring concern-trolling going around HN right now.

Well astrophysicists are asking questions too, so it doesn't seem that information has been disseminated well:

https://twitter.com/AscendingNode/status/961086031784235008

I realize deep space collision risk is very low. I saw a talk with Alan Stern about New Horizons where he answers someone's question about collision avoidance in the asteroid belt that on a trip out to Pluto you are unlikely to encounter anything larger than a grain of sand. But rather than acting annoyed with the person who questioned him, he answered the question well, and I still remember his answer. And let use not forget that space exploration has ethically questionable choices and "improbable" events occur in the past (e.g., Laika, artificial radiation belts from nukes, debris from an RF reflecting foil cloud).

I don't understand. The question you link to is about orbit stability, not the risk of collision and planetary protection. The risk of collision is infinitesimal regardless.

But in any case, I'm happy with with earnest questions about math/science. What's boring and distracting are these expressions of concern about rule violations. Consider: would the original comment of NathanKP have been popular if he asked "I wonder what the chances are that the Tesla will collide with an asteroid?" No. Maybe someone would have quickly pointed to a calculation or estimate, but it would't be at the top of the thread without the emotional appeal that someone somewhere might be breaking a rule.

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