Mars Sample Return – The Challenge for Mankind

Mars Sample Return – The Challenge for Mankind

Mankind is taking the boldest but riskiest step in all human history – the return of samples from the surface of Mars.

There are many signs Mars has life (see the list on the Overview of Mars page on this site). (On mobile devices the menu of pages is at the upper right). If Mars bacteria is pathogenic to human, animal, plant, or microbial life on Earth, the risk of sample return cannot be quantified. Even if returned Mars life could thrive in any niche of Earth’s environment, the risk of this sample return being an invasive species is beyond computation.

Although Space Authorities will surely plan to use the highest Bio Safety Level 4 containment facility to house returned Mars samples, mistakes and accidents are always possible. Examples of mistakes and accidents in highly technical endeavors are obvious (for example, Chernobyl, Fukushima, Three Mile Island in the nuclear power industry, and Columbia and Challenger in the Space Shuttle program.) The choice mankind can make is to continue to study Mars by landing probes on the surface of Mars and NOT return samples to Earth. Even if this takes decades longer to study Mars than returning samples, what’s the rush? Especially when the safety of mankind and our one planet Earth is at risk. We are not yet through the Covid-19 Pandemic. Why risk even worse by potentially returning Mars bacteria to Earth? Do you agree that studying Mars by landing spacecraft there and NOT returning samples is a safer option?

To provide a short comment, simply scroll down. All comments appreciated!


For NASA, or any other nation, to bring Martin rocks containing possible viable microbes back to Earth is a very bad idea. We already know that by “pushing Pangea “ together with mixing the Earth’s biogeographic realms bye intercontinental trade has, to no small amount, added to the current, ongoing mass extinction event. For NASA to say that there has been long-standing “Martian meteor showers “ without negative consequences implies to me an ignorance or denial of the five other known major extinction events (along with numerous minor ones). While we have data that physical forces played a major role in the K-T meteor event, there is much less data on the others, including the massive end Permian . Panspermia could have played a role. Martian life, if it exists, should be studied on Mars, and left on Mars.

I think the risk is slight, but admittedly we have no way of knowing. I have always thought that an isolated lab, either on the space station, or, one day, on the moon, would be the ideal place where such samples should be returned.

I am sure the scientists will take all the necessary precautions to ensure that they are studied without releasing any symbiotes.

Though we need to be careful on what is returned to Earth from Mars…we need to be equally, or even moreso, concerned about contaminating and polluting Mars, as we humans are so famous on doing that to whatever we touch or encounter.

Just look at all the damage we’ve done to our own planet.

I think there does need to be an open discussion as to sample handling/containment protocol. We do not want this to turn into a political fiasco but I just want to hear from the experts – I think after a year of a nasty virus we are owed an open discussion or “presentation.”

Totally agree and I am confident that they will take every precaution necessary (even biowar laboratory level). I am not sure “sterile” is the proper protocol for scientific analysis nor am I sure we want any of it anywhere near the ISS – they are not a high level bio lab. It is an interesting discussion and bears further analysis – one of which I will take up with my neighbor who has a PhD in microbiology and works for the CDC.

That sample won’t be picked up for 10 years or more. I think I trust the woman and men of NASA to keep those samples from having that possibility. Lunar dust is highly allergic to some, and one astronaut was highly affected by it. We take precautions to avoid that

Steve, Thanks. It is a serious issue, and it probably does come down to trusting NASA scientists, engineers, and technicians. It’s not hard to recall times when even the finest make mistakes though. Be well.

They want to find microbes organisms and take them back to Earth in 2031… Luckily the actual pandemic will be just finished by 2031 and we’ll be ready to start an extra-terrestrial pandemic..

With more collective global action and release of testing after such visits, further pandemics might be avoided or at least treated much earlier.

The protocols are already in place for such I’m sure. Maybe a detailed knowledge of what exactly they are would help to relieve your ongoing fear.

Science must go forward those who fear contamination need to read how complex this mission is obviously those concerns were taken into consideration

Concerning oneself with viruses or bacteria returning to Earth with the Martian samples that Perseverance will collect is plain and simple fearmongering. The likelihood that any viruses or bacteria exists on Mars today is remote. If indeed any life exists on Mars today that first sprung up in the planet’s ancient past, that life would have long ago made its way to Earth inside of meteorites.

As society, when dealing with the unknown, we need due caution to ensure that we do not end up bringing to this earth some stuff that may get us into worse troubles.

We have done tests on samples from Mars. Nasa sent a whole science laboratory there, called MSL or the Curiosity rover. They found evidence of water but not life. The places they do tests on these samples are pretty well sterile, mostly to keep earthly contaminants out. But I’m sure they want to keep the samples contained also.

Yes there a risk. But this one is “controlled”.

The same as the risk of sending an earthian virus on Mars.
This is why all the landing parts/vehicules/… are sterilised before take-off.

The bigger risks Earth is facing the multiples bacterias-viruses-molecules-… that we will have to live with in the coming decades/centuries with the melting of the polar ice and the melting of the permafrost and the modification/disparition of the forests… that moves their inhabitants (animals) closer to our cities…

Maybe some interstellar viruses are already on Earth, thank to meteors for example

Yves, thanks for your comments but I’ll have to disagree. Your point that the risk is “controlled”, and that it is the same risk as sending an Earth virus to Mars, is not convincing. The consequence of an Earth virus destroying the biosphere of Mars is concerning, but the consequence of a Mars virus destroying Earth’s biosphere is devastating to humanity. Of course I agree we face other devastating changes with climate change, but that doesn’t mean we need to add to the risks by returning a potential Mars virus or bacteria or invasive species here.
Lastly, you may be correct that some interstellar viruses (or bacteria) may be on Earth thanks to meteors. Maybe. But Mars has had billions of years to evolve some bacteria or virus, which may have never reached Earth and survived the trip by meteor. NASA and China carefully returning them in a spaceship will make survival much more likely. I don’t understand why you feel ok with taking the chance, or how scientists can feel justified in subjecting the rest of humanity to that risk. Mistakes, accidents, and intentional acts occur. Thanks for the discussion! Be well.

Yes. We don’t know what risks there may be.

However, Martian material has been arriving on Earth for billions of years in the form of meteorites — material ejected from the surface of mars from the impact of meteorites, flung into diverse orbits; some of which have intersected Earth, falling through Earth’s atmosphere where thy have lain in the biosphere ever since. These may have provided the vehicles by which a broad sample of any “life-like” Martian entities (or other more or less “bio-active” invaders) could have travelled to Earth.

Alternatively, some entities like viruses, for example, or other complex aggregate molecules, may not need a tangible vehicle; they could just float through the cosmos and populate any favourable destination. These ideas are not new. Earth (and the solar system generally) is bathed in a stream of material from throughout the cosmos, some from “near at hand”, like the tails of comets, and other from farther afield, like cosmic rays and slower-moving inter-stellar “dust”; or more substantial objects like Oumuamua.

And more complex entities may have been able to make such journeys. Consider, for example, the strange organism called the tardigrade, which has amazing survival qualities.,called%20them%20little%20water%20bears.

Finally, samples have already been collected and returned to Earth from the Moon and elsewhere.

My feeling is that the risks posed by Martian sampling, while unquantifiable, are probably benign. 🙂

Clint, thanks for your comments! I agree with many, and I also think panspermia has likely occurred. However, I think there are some concerns about Mars sample return anyway. For example, lithopanspermia from Mars may not have delivered viable life from Mars to Earth that represents all of the life there, while a protected ride in a NASA canister might deliver something that couldn’t have survived a trip via meteor. Also, I’m not worried about the free space panspermia – I agree that stuff must have been showering Earth since the beginning. But Mars life has had billions of years to evolve something (even a bacteria or virus) dangerous to Earth life. (Again, something that a random meteor didn’t blast here, or something that wouldn’t have survived the trip.). But, I agree the risk is small – but since we have only one Earth, I’m hesitant to take that risk. I prefer to study Mars life on Mars, or at worst, the ISS. And then morally, how can scientists choose to expose the billions of fellow inhabitants of the Earth to the risk when some don’t want to be forced to accept that (even small) risk. Again, thanks for your comments!

In such a sterile environment the samples may contain bacteria that help mankind, that’s the chance we have taken in all exploration

Antibiotic resistant suberbugs being created with huge antibiotic use in extremely crowded factory farms, climate change expanding where viruses can live, we’re in a pandemic due to people refusing to follow basic health. Dead/nonexistent/quarantined microbe samples not on list of concerns.

certainly it is safer and technically more correct to study the microbes of Mars in their environment, i.e. on Mars (assuming they exist!) but it is equally certain that studying them on Earth is much simpler and less expensive and if you take the adequate safety measures also not dangerous.

If we believe that life was only created on Earth, how do we know that meteors hitting Earth didn’t blow bacteria to Mars?

nope. Unless you’re counting the meteorites found on Earth that had been determined to be blasted off Mars millions of years ago. One famous meteorite (ALH84001) even has controversial signs of fossilized bacteria, but none had live bacteria, as far as it is known.

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