Tardigrades: We're now polluting the moon with near indestructible little creatures

Tardigrades: we're now polluting the moon with near indestructible little creatures
Credit: 3DStock/Shutterstock

An Israeli spacecraft called Beresheet almost made it to the moon in April. It took a selfie with the lunar surface in the background, but then lost contact with Earth and presumably crashed onto the lunar surface. Now it's been revealed that the mission was carrying a cargo of dehydrated microscopic lifeforms known as tardigrades.

Beresheet was the first stage of a privately-funded initiative to transfer living DNA to the moon. The project is designed to act as Noah's Ark Mark II, providing a repository from which plants and animals could be regenerated to repopulate the Earth should a catastrophe akin to a flood of biblical proportions overtake the planet.

Whether the project is far-sighted or foolish, what has roused interest is the fact that, as a result of the crash, the tardigrades may now be scattered across the . They are hardy creatures and could probably survive on the moon for a long time. Is this a matter of concern? I believe so, but possibly not for the reasons you might think.

Tardigrades are odd little creatures. Measuring up to about half a millimetre long, they have four pairs of stubby legs and a front-end that even the fondest parent couldn't describe as beautiful. Striking, or distinctive, are my adjectives of choice. Moon-faced would be appropriate, given the context of the story—with a rounded, sucker-like structure in the centre that can project outwards, revealing a set of dangerous-looking sharp teeth.

They're often called "water bears" but the images of tardigrades that I have seen remind me of a slightly over-inflated blimp, one of those large balloons that float overhead at carnivals. The legs stick out at a slight angle, as if they are too swollen to stand upright. And that is probably the clue as to why it is extremely unlikely that the creatures will survive indefinitely on the moon.

Tardigrades: we're now polluting the moon with near indestructible little creatures
Tardigrades in space. Credit: Dotted Yeti/Shutterstock

Tardigrades can survive extremes of temperature and pressure, including the frigid vacuum of space. They don't seem to mind being exposed to radiation and are all-round tough little creatures. When dehydrated, they roll up into a spore-like state that slows down their metabolic rate by about a hundred-fold, enabling them to survive for potentially over 100 years.

But to live their life to the fullest requires water. It's where they get their oxygen and food, typically colonising clumps of algae or burrowing into sediment to ingest nutrients from the fluid of other living creatures, even other tardigrades. So while the tardigrades will technically stay alive on the moon for some length of time in their rolled-up state, unless they are rescued, rehydrated and refuelled, they will eventually perish.

Interplanetary pollution

I'm not concerned about polluting the moon with organisms that might reanimate. My concern is about polluting the moon, full stop. There is already a fairly sizeable amount of debris from redundant spacecraft and litter left behind by astronauts. As more missions are planned to the moon, eventually with human passengers and perhaps even settlements, we must learn to clean up as we go along. Otherwise, we are going to have the sort of crisis that we are seeing on Earth with the outcry about environmental damage from plastics.

There is, though, another question to consider. What if the spacecraft had crashed as it approached Mars rather than the moon? The planet has had a poor record for successful landings, although it is much improved in the past decade. Would the tardigrades have survived atmospheric entry? Even though the atmosphere of Mars is thin, it still provides sufficient resistance to cause serious damage to the outer shell of an entry vehicle.

Tardigrades: we're now polluting the moon with near indestructible little creatures
The surface of Mars should be kept pristine. Credit: NASA

If they had survived, would they ultimately be any more successfully on Mars than on the moon? We know there is plenty of ice below the immediate surface across much of the planet. Would an impacting spacecraft transfer sufficient energy to melt a local region of ice? Could that meltwater survive without sublimating away or refreezing for long enough that the tardigrades rehydrate and wake up?

I have no idea, but let's speculate that the answer to the two questions is "yes", and that following a crash, a flock (herd? shoal? pack?) of tardigrades reactivates. What happens next? As detailed above, tardigrades need water to survive, not just to rehydrate them. They live on fluids derived from other living beings. And, as far as we know, there are no living beings on Mars.

But we still keep sending spacecraft to look for life. Sending a cargo of tardigrades to Mars would be irresponsible, even if we don't believe they would survive. Irresponsible because Mars has the potential for life. Restricted life, for sure, but we have no right to endanger that life. And we have a responsibility to maintain Mars as close to pristine as possible, exploring it with care.

That is why space agencies take such stringent precautions about spacecraft construction. The rooms in which the craft are built are cleaner and more sterile than any operating theatre. They take every precaution to ensure that no terrestrial life is transferred to Mars.

NASA and ESA are currently planning a mission to return samples from Mars to Earth. And precautions about the possibility of returning Martian life to Earth with the rocks are central to the design and build of the spacecraft.

Last week, we had an asteroid passing close to the Earth. Next week, maybe it will be killer bees. Or a plague of thieving magpies. But for now it is water bears on the . We should let them shrivel slowly into oblivion.


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Hordes of Earth's toughest creatures may now be living on Moon

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Aug 09, 2019
idiots. you cannot pollute a permanent vacuum awash with high energy photons and cosmic rays.

Aug 09, 2019
The population bomb; global warming; deforestation; fishery collapse; the refugee crisis; mass shootings; depleted aquifers; our crumbling national infrastructure; terrorism and tardigrades surviving on Mars.

You know you're living the good life when the last of these is the first of your worries!

Aug 09, 2019
Just as pieces of Mars and the moon end up on earth as meteorites. So pieces of Earth rocks must land on the Moon. These earthites might well contain Tardigrades and more probably DNA. And certainly in the future will contain microplastic.

Aug 10, 2019
Given how big a deal is being made over this, I'm starting to wonder if this isn't anti-Semitism, particularly since everyone seems to agree the tardigrades won't last long in the lunar environment.

Aug 10, 2019
"Tardigrades: We're now polluting the moon with near indestructible little creatures
by Monica Grady, The Conversation"

-POLLUTING the MOON with BUGS oh no!

From the Constipation, queen of trolls.

-no wait-

"My concern is about polluting the moon, full stop"

-because it's the MOON, and its dirty humans, and its GARBAGE!!! Think Everest.

"The surface area of the Moon is 37.9 million square kilometers. That sounds like a lot, but it's actually smaller than the continent of Asia, which is only 44.4 million square km." ['ONLY']

Get ready for junkyards and Superfund sites cigarette butts all over the place.

Christ.

Aug 10, 2019
Re large moons
https://www.bbc.c...p02xv7ds

-keywords: pollution, projection, trigger, shaming, michael Moore

So hard to distinguish sometimes between the inner and the outer, you know?

I think this is a setup-
Given how big a deal is being made over this, I'm starting to wonder if this isn't anti-Semitism, particularly since everyone seems to agree the tardigrades won't last long in the lunar environment
This is confusing. Are you referring to Hitler's plan to send german Jews to Madagascar? Or a reference to aussie penal colonies? For as we know, that worked out pretty well (but not for the indigenes as it turned out)

Aug 10, 2019
"The surface of Mars should be kept pristine."

-Because dust and debris has a beauty all it's own.

Best not to tell her about the strip mines and culm dumps and spaceport tarmac and plowshare nukes. I'm guessing dr/sir/dame? Grady would not favor terraforming?

Aug 11, 2019
All I can say is:

"Move over, microbe!"

In other words: Send lichens and tardigrades to Mars. Maybe these can do a better job at reviving the planet than any autochthonous microbes there.

Aug 11, 2019
All I can say is:

"Move over, microbe!"

In other words: Send lichens and tardigrades to Mars. Maybe these can do a better job at reviving the planet than any autochthonous microbes there.
The planets fine the way it is. Our rivers have proven that machines love mars. Millions of martians will be living in comfort and security in vast underground cities by the time terraforming becomes possible. They will be relying on an extensive industrial and power-generating infrastructure on the surface and will not allow earther carpetbaggers to ruin it with rain and muck and insects and rust and mold.

Human tech will allow us to adapt to new extremes found on many worlds. We won't be forcing them to adapt to us.

There will never be more than a few million humans on mars unless we let religion establish itself there, and we won't. Earths pops will eventually shrink to under a few billion. This is the new ear of quality over quantity, of a mature and sustainable species.

Aug 11, 2019
Errata:
rivers = rovers
ear = era

Aug 11, 2019
Another mess brought to us by scientists, gotta love their naive narrow-minded "intelligence".

Aug 11, 2019
Errata:
rivers = rovers
ear = era


It's still word salad.

Aug 11, 2019
Errata:
rivers = rovers
ear = era


It's still word salad.
-Meaning you dont understand it or you disagree with it? Which?

Aug 12, 2019
It's still word salad.
-Meaning you dont understand it or you disagree with it? Which?


Meaning it's a bunch of irrelevant hooey.

Aug 12, 2019
It's still word salad.
-Meaning you dont understand it or you disagree with it? Which?


Meaning it's a bunch of irrelevant hooey.
-Meaning you're just some old blowhard with no real opinion.

I get it.

Aug 12, 2019
-Meaning you're just some old blowhard with no real opinion.

I get it.

It is a valid opinion to say your post is hooey. I even agree with it.

Aug 12, 2019
But you ought to try and explain why or it's really kind of worthless dont you think? You afraid of losing your faith?

Aug 12, 2019
Mostly because of bashing the religious and facts like "machines love mars" and earths' population shrinking.

You also could put some reason behind these. Like why our machines love mars? Why would religion make population larger and why would earths' population drop largely?

Aug 12, 2019
Guess you dont read the news?

"Spirit and Opportunity landed on Mars January 3 and January 24, 2004 PST (Jan. 4 and Jan. 25 UTC). Both rovers lived well beyond their planned 90-day missions. Opportunity worked nearly 15 years on Mars"

-Most all have.

"Why have religions determined to prevent family planning? The answer is in a kind of survival of the fittest amongst religions themselves. As most religious people simply abide by the religion of their parents[5], religions that encourage parents to have more children will attain a stronger and longer-lasting base of adherents. Barber (2011) notes that religions promote fertility by encouraging marriage at a much earlier age than amongst the non-religious"

-Theyre being kind. The surviving religions are the ones that were better at outgrowing and overrunning their now-extinct counterparts.

"Give no thought for the morrow"
"Children of our youth"
"Be fruitful and Fill up the earth"
Etcetc

Aug 12, 2019
"The average birth rate in the European Union is 1.6, well below the 2.1 live births per woman needed to sustain a population, and the global average of 2.4."

-Western culture emancipates women. When they are in control of their lives they naturally have fewer babies.

To recap:
1) No water, corrosion, mold, etc on mars.
2) religions force overgrowth; "warfare of the cradle" - teddy roosevelt
3) western pops are shrinking because of the secular culture (and the ONE BILLION ABORTIONS post 1973)
4) you would know these things if you had been paying attention

Aug 13, 2019
There are also many machines that clearly hate mars: http://www.astron...missions

Population shrinking to few billion? You honestly think Earth can survive one billion? First time I read shrinking to few million which I also doubt. I think you have some hard time with numbers if you think there's already billion abortions done.

If you think religions like they were a thousand years ago, then yes they might courage making babies. But modern religions, no.

How about if the marsers decide that they want to populate the planet quick and produce massive amounts of babies. Maybe to wage war with earth or maybe to populate others planets. I wouldn't count on having only few million people on mars.

Nevertheless, you stated the things as clear facts yet they can be questioned. That's why your post was hooey. All opinions without facts.


Aug 13, 2019
Nope.

"usually well before they approached the Red Planet, either because of launch failure or some error on its outward trip"

-Once they get there they work far better than they do here.
Population shrinking to few billion? You honestly think Earth can survive one billion?
"The current world population is 7.7 billion as of June 2019"

-Youre either uncommonly uninformed or you're trolling me.
I think you have some hard time with numbers if you think there's already billion abortions done
Over ONE BILLION.
http://www.johnst...318.html

-Many sources. Which you would have found if you had bothered to look.
But modern religions, no
Really. What's stopping them? Where in your holy book does it say that 2.1 children per family is plenty?

It says just the opposite. They all do.
All opinions without facts
Aw you're just scared to google my quotes. Most of this is common knowledge.

The US ABORTS 20% of all pregnancies.

Aug 13, 2019
idiots. you cannot pollute a permanent vacuum awash with high energy photons and cosmic rays.
LOL if it's awash with HE photons and cosmic rays it is, by definition, not a vacuum...

Aug 13, 2019
"TOTAL, 1921 - 2018: 941,600,000 reported abortions, estimated 1,052,600,000 total abortions
Estimated current rates: 11,650,000 abortions per year or 970,000 abortions per month."

-Plus a similar number never conceived due to birth control. They and their decendents to the 3rd and 4th gen, never born. Perhaps 1/3 to 1/2 the world's population. And ONLY in countries and regions where religion can no longer prevent it.

Elsewhere religion-driven overgrowth is causing war, famine, ecological devastation. And millions of excess peoples, desperate refugees, are flooding across our borders.

Aug 13, 2019
Sorry Otto, I always forgot that American billion is a milliard. Then your numbers make a lot more sense.

Modern religions, as I see them, are about helping the ones in need. Not so much in gaining power and more foothold.

I should google sources for your arguments? It does not work that way.

Aug 13, 2019
Modern religions, as I see them, are about helping the ones in need. Not so much in gaining power and more foothold
Religious charities give to believers or potential converts.

"Zakat cannot to be given to non-Muslims in any way shape or form, not even under the account of those whose hearts are softened." [Prevailing opinion]

"3 No good ever comes to a person who gives comfort to the wicked; it is not a righteous act.[b] 4 Give to religious people, but don't help sinners. 5 Do good to humble people, but don't give anything to those who are not devout. Don't give them food, or they will use your kindness against you. Every good thing you do for such people will bring you twice as much trouble in return. 6 The Most High himself hates sinners, and he will punish them. 7 Give to good people, but do not help sinners." Sirach12 catholic canon

-The largest charities are secular. Mother Teresa didn't love the poor, she loved poverty which is why she did nothing to end it.

Etc.

Aug 13, 2019
I should google sources for your arguments? It does not work that way
I tend to check what others post here a lot because it is often the way to trip them up. I present facts, usually as quotes from reputable sources. Like I say, the stuff I dont ref is stuff I assume is common knowledge. You should google them to educate yourself.

Or stay stupid and declare them false. Suit yourself.

You declared that things I posted were false without checking them. That is disrespectful and irresponsible.

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