For those who don’t know the background, NASA’s Perseverance rover is gathering rock samples in Jezero crater on Mars where there used to be a delta long ago. It is a very interesting place for past life. The samples are in tubes on Mars. They want to return them some time around 2033.

Sadly Perseverance can’t drill and the surface deposits have been sterilized by ionizing radiation for billions of years. Though Mars used to have oceans it’s been dry now for billions of years but sometimes with occasional flooding and even lakes for a while.

I am trying to find out what has happened as NASA are normally so careful. The analogy of the smoke detector I think is the best way to think of it.

The risk is very low as they aren't even looking for life there, and most astrobiologists think it's not likely there's lots of life on Mars.

They CAN return it 100% safe by sterilizing the samples. I'm working to try to get attention of the right people as that will end up with a better mission too from their point of view, lower cost or much better science if they add the bonus astrobiology samples.

What has me baffled is why they don't even considering this option.

I think even if they do go through with this NEPA process using a BSL-4 for an unsterilized return, the presidential directive will stop them. The president has to look at anything with potential to lead to allegations of large scale or long term effects, even if the agency thinks there is no risk.

I'm doing my best to try to find out what happened and to get clear answers that NASA are now aware of the research they didn't cite in the statement and what they plan to do about it. Or a clear reason why they left it out and why they don't think it needs to be considered (though I can't think what such a reason could be).

This isn’t something to be scared of. Margaret Race’s analogy of a smoke alarm is a good way of thinking about it especially for this first mainly geological mission from Mars. But we do need smoke alarms in a modern house and this is our “house” for billions of people.

The risks are low but it's prudent to be careful - it even costs them less to sterilize the samples to keep Earth safe while preserving virtually all the same science.

Do comment on the proposal with your thoughts, they are asking for feedback and do share this post if you want to do something about it.

NASA

- Do Listen To Public Concerns About Life In Samples From Mars

- Your Plan Is Like Building Us A House Without Smoke Alarms

Please share widely and comment on their plans - comments close Dec. 20

TEXT ON GRAPHIC

We need to install “smoke detectors” to protect Earth.

The risk of large scale effects from NASA’s mission is likely very low - indeed unlikely it returns life at all but it’s not demonstrably zero.

The risk of a fire to your house is also low.

We need the smoke detectors just in case. Especially for a “house” for billions of people.

Especially as we likely have many future missions like this from many countries.

graphics: File:Smoke detector.JPG - Wikimedia Commons

also: https://www.flickr.com/photos/lafd/40194010602

also: https://commons.wikimedia.org/wiki/File:Fire-Extinguisher.JPG|thumb|Fossil

See my blog post:

. NASA - Do Listen To Public Concerns About Life In Samples From Mars - Your Plan Is Like Building Us A House Without Smoke Alarms

That is a short post about the main points of concern.

NASA

- Your Samples From Mars Need A Better Than Biosafety Level 4 Facility

- NOT Designed To Contain Even Earth's Tiniest Cells

TEXT ON GRAPHIC

… the ESF-ESSC Study Group recommends that values on level of assurance and maximum size of released particle are re-evaluated on a regular basis.

The release of a single unsterilised particle larger than 0.05 microns is not acceptable under any circumstance

WELL BELOW Biosafety 4 limits - we don’t have ANY air filters yet that can do this

Page 48 of 2012. Mars Sample Return backward contamination–Strategic advice and requirements

My blog post: NASA - Your Samples From Mars Need A Better Than Biosafety Level 4 Facility - NOT Designed To Contain Even Earth's Tiniest Cells

That one is a longer post quoting from the Environmental Impact Statement and also I share a copy of the statement annotated in Word and go into lots of technical details.

Dear Space Explorers

- Yes We Do Need To Protect Ourselves And Earth From Any Microbes In Mars Rocks As We Explore

TEXT ON GRAPHIC

Some microbes may be able to get from Mars to Earth - what matters for invasive species are the ones that can’t.

Barn swallow - can cross Atlantic

Starling - invasive species in the Americas

Didymosphenia geminata invasive diatom in Great Lakes and New Zealand, can't even cross oceans.

Starling photo from: File:Starling - Flickr - TrotterFechan.jpg - Wikimedia Commons

Barn swallow photo from File:Starling - Flickr - TrotterFechan.jpg - Wikimedia Commons

Didymosphenia geminata (Lyngb.) from: Species Profile - Didymosphenia geminata

My blog post: Dear Space Explorers - Yes We Do Need To Protect Ourselves And Earth From Any Microbes In Mars Rocks As We Explore

That one is a longer post focusing on the importance to space explorers and colonization enthusiasts that we stay safe as we explore the solar system.

DO COMMENT

Everyone - do comment if you have thoughts about the project - go here, and click on the blue button to the left:

Text in red: Comment period ends on 20th December

(blue button to the left, circled with a red dashed line)

Click here to comment

This is where you go to comment:

. National Environmental Policy Act; Mars Sample Return Campaign

You don't need to be an expert. It's a request for public feedback as for any big project like building a reservoir or an oil pipeline.

This post as a tweet thread:

MORE BACKGROUND - MARS LOOKS DRY BUT MAY HAVE LIFE

However though Mars looks completely dry, it has some briny seeps just below the surface of the sand dunes in places. In Jezero crater they probably form only briefly in the early morning and late at night but in other places they can last longer. Most of the brines are far too salty for life and they take up the water at night - but at times they take up enough water for life as we know it to be possible except that it is then very cold, -70 C because the atmosphere gets most humid when it is very cold.

Modern Mars looks totally inhospitable from space – but it has a thin atmosphere and Curiosity found very cold salty brines that sometimes form overnight in Gale crater – the same process should happen in Jezero crater – though too cold for terrestrial life these brines might be habitable to biofilms that retain the water through to daytime when it gets warmer.

[Arrow points to Gale crater]

These brines may also be habitable to Martian life if it can withstand lower temperatures.

Image from How to Search for Life on Mars,

However we get life in very inhospitable places using biofilms where microbes work together in a community to make a kind of microbial home that is wetter or has more organics or protected from UV or in other ways more habitable. Possibly even Jezero crater might have these little biofilm homes especially for Martian microbes that adapted and evolved on Mars for billions of years.

How EPS (extrapolymeric substances) can make a “home” of the hostile Martian surface.

Some of the environment stressors

100% humidity varies to 0%

Heat, cold, UV, dust storms

Oxidants, nutrients

Algae may add oxygen

Retains moisture from night to daytime when temperature soars from -70°C to above 0°C.

Cryoprotectants - protects from cold shock

Extrapolymeric substances (EPS): proteins, DNA, lipids, polysaccharides, other large organic molecules.

A biofilm is like a microbe’s “house” which can keep it warm, wet, protected from UV and which it shares with other microbes.

SO THE MOST OPTIMISTIC CAN SEE POTENTIAL FOR MARTIAN LIFE ALMOST ANYWHERE, LEAST OPTIMISTIC THINK THOUGH THERE ARE LIKELY MICROHABITATS ON THE SURFACE IT MIGHT BE REALLY HARD FOR LIFE TO GET INTO THEM SO IT IS STUCK UNDERGROUND OR MAYBE GONE EXTINCT OR NEVER EVOLVED

So you get many different ideas about how possible or not present day Mars life is. If you go by the most optimistic it’s possible that Perseverance returns life, perhaps as viable spores in the dust. If you go by the least optimistic there may be almost no life or none at all, there may well be habitats, but perhaps life went extinct millions of years ago or spreads so slowly it never got to them and only lives deep below the surface today. So those are basically the two main streams of thought in modern astrobiology, life deep below the surface or not there at all, and life much more common - but even the most optimistic would say it’s still rare, patchy, a few patches here and there in a vast desert, sometimes a thin biofilm, sometimes a few thousand cells per gram of dirt - that’s by analogy with the most inhospitable deserts on Earth which are probably roughly as habitable as the most hospitable deserts on Mars.

WHATEVER HAPPENS, A FEW MICROBES IN BIOFILMS IN DESERTS ON MARS SEEM HARMLESS AND MAYBE THEY ARE - BUT THERE’S THE “WHAT IF”S - WHAT IF IT IS INDEPENDENTLY EVOLVED LIFE WITH EXTRA BASES, OR DIFFERENT AMINO ACIDS, OR MAYBE EVEN EVOLUTIUON TOOK ANOTHER DIRECTION AND IT’S MIRROR LIFE - WOULD IT STILL BE OKAY TO MIX WITH TERRESTRIAL LIFE? AND EVEN MICROBES CAN BE INVASIVE LIKE THE INVASIVE DIATOMS IN NEW ZEALAND

So - you’d think that sounds harmless. And perhaps it is. Maybe even beneficial to Earth life, it may be able to live in places terrestrial life can’t and help green our most barren deserts or the deserted areas of our seas. The entire domain of achaea is largely beneficial to other forms of life.

But we don’t know what is there and you can think of other scenarios where it might be harmful. Individual species, opportunistic molds, say, or pathogens of biofilms that can also live in human lungs, molds that can grow on crops. Algal blooms that could be toxic. Or it might be a novel type of life with e.g. more or different bases like Hachimoji DNA with 8 bases instead of 4 which has been made in the labs but is safe because it depends on chemicals that only exist in the lab. Or, and this is my example, mirror life. That is life which evolved from the get go in the opposite direction with its DNA spiralling the other way, and all its starches, proteins, enzymes reflected as in a mirror. So what happens if half the microbes in a biosphere are mirror life? Itr might not work very well. Even worse the mirror life might eat ordinary organics but ordinary life not be able to eat it.

THIS DOESN’T MEAN ANY OF THIS IS LIKELY JUST THAT WE NEED TO TAKE PRUDENT PRECAUTIONS UNTIL WE KNOW WHAT IS THERE - AND IUF WE DO FIND SOMETHING LIKE MIRROR LIFE, SAY, WE MAY NEED TO TAKE SPECIAL CARE INDEFINITELY SO IT’S NOT JUST A FORMALITY - IT IS SOMETHING WE NEED TO DO IN CASE WHAT IS THERE REALLY IS HAZARDOUS IF RETURNED TO OUR BIOSPHERE - THOUGH MOST THINK THE POSSIBILITY OF THAT IS LOW

That doesn’t mean any of that is likely. It is just that we do need to know what is there, what lives on Mars before we know what precautions we need to take, if any.

Until we know that it’s safest of all to just pre-sterilize everything returned from Mars before it gets here.

Anyway NASA are usually so careful and I’m baffled at what is happening here. They are cutting corners and that’s the puzzle..

So - given that we know how to keep Earth 100% safe by pre-sterilizing the samples before they come to Earth - why not do that? That’s the simplest solution and it makes so little difference to the science - the motivation for doing anything else isn’t; very compelling if y ou have that as an option.

But NASA has made it not an option in this statement.

That is what is so baffling about it, that it doesn’t have a sterilization option and it downplays the very low risk of returning life when all the big sample return studies are clear that we do need to protect Earth.

See also my

. Many Serious Mistakes In NASA's Samples From Mars Environmental Impact Statement - Proposals For A Way Forward