Satellite detects large mass of water in Mars canyon | Hacker News Reader

Satellite detects large mass of water in Mars canyon

cnn.com

259 pointsChuckMcM113 comments

The FREND instrument searches for neutrons to map hydrogen content in the Martian soil.

FREND revealed an area with an unusually large amount of hydrogen in the colossal Valles Marineris canyon system: assuming the hydrogen we see is bound into water molecules, as much as 40% of the near-surface material in this region appears to be water.

How confident are we that hydrogen detected really is water?

I don't think there are many plausible alternatives, really.

There just aren't alternatives to what it could be.

Hydrogen just doesn't get bound up into minerals (unless essentially as water) and not at any great density, and there isn't another plausible substance that would be hanging out in a canyon on mars.

It could be hydrocarbons. We just found oil on on Mars! Black gold, Tharsis tea! Now if only we had an atmosphere to burn it in.

Isn't that actually one of the terraforming methods proposed?

If there was ever life on Mars at scale it wouldn't be impossible or unusual to find oil and coal, would it? Or does it degrade on the timescales that would be required for this to be possible?

tbc I don't believe there's oil on mars nor do I think it is remotely likely.

Hydrocarbons are quite common on planets without life. It's the oxygen in our atmosphere that makes them rare.

Evidence points to tectonic activity and liquid water on Mars at one point in its history so theoretically, yes. The geological processes that can move fossils deep enough to become fossil fuels could have been present along with the mud slides and sediment that are most favorable for preserving animal remains.

Earth’s hydrocarbons are a unique result of the evolution of life here. See the Carboniferous era.

Planets with confirmed life are a sample size of one. For the moment, having corporeal form is unique to life here.

Well, yes, but I was just pointing out that not all life is likely to become hydrocarbons. It was kind of a fluke.

Life is very likely to be carbon based (what other element makes 4 bonds, as is necessary for 3D structures?). Where life is carbon-based, decaying life in the absence of oxygen produces hydrocarbons.

There is silicon. Some sci-fi authors have postulated silicon-based life in their stories. (It’s been too long, I don’t remember which.) As with most science fiction, how plausible that is, is a different matter altogether.

Earths, yes, but there are hydrocarbons elsewhere that are not biological in origin.

“Methane (CH4) is abundant on the giant planets—Jupiter, Saturn, Uranus and Neptune—where it was the product of chemical processing of primordial solar nebula material. On Earth, though, methane is special. Of the 1,750 parts per billion by volume (ppbv) of methane in Earth’s atmosphere, 90 to 95 percent is biological in origin.”[1]

[1] https://www.scientificamerican.com/article/methane-on-mars-t...

Why stop there. It could be an ancient Martian landfill where plastics failed to degrade.

Heck, without microbes it could just be Martian mummies.

Why burn perfectly good hydrocarbons when you can produce various plastics out of it, for the needs of your growing colony?

when plastic on mount Everest was not far enough ;)

We dont have 200 millions years to wait for Mars reforestation, so plastic > wood

Also I was making a joke

Ammonia, NH_3?

I’m pretty sure Mars is too warm to have solid surface ammonia

very possible!!!! In fact, the ground temperatures at the rover landing sites swing up during the day and down again during the night, varying by up to 113 degrees Celsius (or 235 degrees Fahrenheit) per Mars day. https://mars.nasa.gov/mer/mission/rover/temperature/

Melting (freezing) point 195.42K-77.73°C

https://www.engineeringtoolbox.com/ammonia-d_1413.html

Those temps for the freezing point will be for pressures above the triple point of ammonia, or pressures you’d find on earth.

The pressure on mars is too low for liquid ammonia to exist and the freezing/sublimation temperature is more like 180K or -100C

And to exist underground in large amounts for millions or billions of years it’s not good enough for temperatures to occasionally be low enough to freeze ammonia, when it was warmer the ammonia would turn into gas and blow away so unless there is a significant local source of ammonia it is highly doubtful that is where the hydrogen comes from.

Is water on Mars even exciting? We're already quite certain there is a ton of water on Mars... in the form of ice. The exciting discoveries are evidence of liquid water.

> The bulk of the northern ice cap consists of water ice; it also has a thin seasonal veneer of dry ice, solid carbon dioxide. Each winter the ice cap grows by adding 1.5 to 2 m of dry ice.

> The part of the cap that survives the summer is called the north residual cap and is made of water ice. This water ice is believed to be as much as three kilometers thick.

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

That's a lot of water!

For anyone born in the 20th century I’d think so.

If you’d have said there was water on mars in 1970 you’d have been met with disbelief. 1980? 1990? Later?

I think this is a failure of science education more than anything else. The polar ice caps of Mars were first observed in the 17th century.

https://en.wikipedia.org/wiki/History_of_Mars_observation#Ea...

It was observed simultaneously as canals and vegetation were "observed", and roundly discarded by 1970s. Water on Mars remained unconfirmed until this century.

Though I distinctly remember reading in an encyclopedia from the '70s that certain large dark regions on the Martian surface were believed to be thick vegetation (: I'm not kidding!

From [1]: "As recently as the early 1960s, it still seemed possible to a few astronomers that the dark regions had some kind of plant life because they seemed to darken each summer as if plants were growing in response to sunlight."

[1] https://www.jpl.nasa.gov/images/pia02362-the-dark-surfaces-o...

Yes, I remember reading books from the 60s my grandmother got from a charity shop. They had wonderful illustrations of Mars with vegetation and where the canyons discussed in the article were canals full of water. It's easy to forget just how much we've discovered about the other planets in the solar system in the last 50 years.

There is so much science fiction writing from the golden age and beyond, up to the 60s and 70s, which prominently features Martians and Martian cities. Mars having alien life was a massive source of speculation among the public at that time. While the stories are still great, reading them today I can't help but go "nah we've been to Mars, there's nothing there".

Makes me think about how soon sci-fi written today will get similarly outdated.

I remember a sci-fi novel from the 60s or 70s, where a forgotten punch card was the only artifact left over from aliens long gone.

I think that something similar awaits modern science fiction in 50 years.

I'm reading Red Mars at the moment, written in the 1990s and set in the 2030s, and a cluttered lab is described as having piles of floppy disks lying around. So, yeah.

Makes one wonder what science of today will be looked upon with quaint humor in 50 years' time.

Astronomy Picture of the Day on April 1st 2005: NASA finds water on mars[0].

[0] https://apod.nasa.gov/apod/ap050401.html

It is very exciting in the equatorial regions as it was typically assumed that because of the high summer temperatures (~70°F), any ice would melt and the water would evaporate. Valles Marineris would be an excellent location for a human settlement because of these warmer temperatures and the higher atmospheric pressure in the canyon. If there is water there as well then it ticks all the boxes.

> higher atmospheric pressure

But the pressure is still effectively nil. It's far below what would be needed for humans to venture outdoors, and makes a negligible difference to the strength required for pressurised buildings.

I believe it would make it easier to land supplies there though, since there is more atmosphere to aerobrake with.

Can you aerobreak all the way into the cannon though?

Every bit helps, right? Even if you're using retrorockets by the time you're that low, atmospheric drag should still be helping.

It is a few hundred kilometers wide.

Absolutely but every little bit helps. A thicker atmosphere also means less radiation, thus less radiation shielding required. I don't have numbers on hand but from what recall it is a significant enough of a difference to worthy consideration.

I am sure someone will eventually come up with the crazy idea to seal the canyon and pressurize it.

The Martian soil is still unsuitable for humans since it's full of toxins.

https://www.space.com/21554-mars-toxic-perchlorate-chemicals...

The same article makes it sound pretty manageable. Showers for the spacesuits, microbes that eat it, and useful properties.

Could human settlers on Mars adapt to progressively lower pressure levels over time (generations)?

Yes and no. Yes because there are people on Earth adapted to living at great heights (the Andes or Himalaya) and no because the pressure on Mars is far too low. At Mars' pressure, the boiling point of water is so low that our body temperature is too high and makes the blood boil.

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

I wonder how much difference it would make to the pumps sucking in Martian air to create fuel and pressurized atmosphere.

If we found microscopic life forms in the water though, would we create a settlement or not? It would be so easy to contaminate stuff with a settlement there. I could see people pushing for it becoming a reservation, only to be studied from very far away using hyper-sterilized robots. At least for a while until we are sure we've exhaustively cataloged everything.

Finding life would be huge, we're not going to just go settle on top of it willy-nilly.

Hasn't stopped us on the local planet.

To an extent, it depends on what we find. What kind of biology does it have? How many species are we talking about? Can we throw it in a bio-bank somewhere and move on? Will it outcompete any Earth life we try to seed? Could it be dangerous if it colonized the Earth?

Earth should be as unsuitable for them as mars is for us, except in the case of non alive organisms like viruses or prions. But to have viruses you need higher forms of life supporting them, those based in cells

If we found some alive in Mars and we could found it quickly if we found a cannon with water, we should call them in a distinct way. I will propose marteviruses:

Marte-herpesvirus, Marte-adenovirus, Marte-coronavirus, etc.

Another way could be putting before a M- prefix but would be less convenient to read

Which is what scares me. Yes it s cool to protect the local microbes but damn arent we also an important local life form of the solar system that would leap one level in evolution by just living on two planets ?

Should we lose that for the sake of microbs, as long as we can preserve them for study?

Contamination goes two ways.

Every deposit of water, even as ice, opens a new series of inquiry. Suddenly you have new regions, geographies, biogeochemical hypotheses, and potential support for life. More history, more to explore.

New sites give us more to consider for future missions and broaden the set of experiments we want to conduct.

I'd much rather keep finding water, even as ice, then have the planet run dry. It only increases the odds.

One of the interesting consequences of water on Mars is the fact that it can be used to make methane and oxygen (used by both SpaceX's Raptor and Blue Origin's BE-4 engines). This potentially increases the amount of cargo one can carry from Earth to Mars as one no longer needs to bring hydrogen (for the Sabatier process for making methane) from Earth for the return trip back to Earth

That sounds like a ridiculous waste of such a scarce resource.

Why? This is one of the only economic advantages for settling mars; serving as a lower-g refueling station.

Unless the water is replenished somehow, sending it all off-planet would mean no one could settle Mars.

How much water do you think is on Mars?

Refueling for what? The realities of orbital dynamics mean that Mars isn’t a convenient stopping place on the way to say, the outer solar system. I don’t have the numbers in my head but the delta-v requirements to intercept, match velocity and land negate any potential refueling benefit in my understanding. (Not to mention the added complexity vs a straight shot, this is a lot to pull off even in a sim like KSP)

You might be able to make an argument for refueling bases on Mar’s tiny moons with their negligible gravity wells for Martian missions themselves but that’s about all I can see.

What am I missing?

You're not missing much, but orbital transfer hooks from Mar's moons work out.

But what if you built a base there that continuously flung refueling pods into orbit? Make these pods leave orbit to rendezvous with another craft somewhere else rather than the craft needing fuel to come to a stop on Mars.

>According to the researchers, 40 percent of the near-surface material of the 15,830 square mile (41,000 square kilometer) region could be water ice.

That’s potentially billions of tons of water ice.

why not methane? CH4

alcohol!

The paper is here: https://www.sciencedirect.com/science/article/pii/S001910352... but it is pay walled.

One of the more interesting challenges in creating self sustaining colonies on other planets is the availability of water. And this is another example of how Mars might provide water in a very accessible way (40% by volume is a lot of water :-))

NASA has already pretty much convinced itself that plants could grow in suitably amended martian soil[1][2]. I haven't seen a paper yet on whether or not there is enough solar irradiation for robust photo synthesis (needed for the production of plant sugars) but one could always add grow lights powered by one of the small nuclear power sources[3].

[1] https://www.nasa.gov/feature/can-plants-grow-with-mars-soil

[2] https://journals.plos.org/plosone/article?id=10.1371/journal....

[3] https://www.forbes.com/sites/jamesconca/2021/12/06/nasa-is-l....

The link you provided for the paper wasn't paywalled for me, no idea why.

It’s not paywalled. OP probably saw the name Elsevier and assumed it was paywalled, but it’s open access and licensed CC BY.

Exactly this.

Heliostats could work too but might be a challenge with the dust storms. At least at first.

What’s the current wisdom on bioremediation of perchlorates? That seems to be the sticking point.

We know on earth that tidal zones have been a hotbed of evolution. I have this notion in my head of creating terraforming equipment (specifically atmosphere and water) that buffers its output and releases it in pulses though a transitional zone. Like a marine fish tank. Say at the bottom of a canyon or partially enclosed space.

This alternating availability of resources should select for more resilient lines.

The thing I don't understand is why aren't we building something here on Earth that is underground designed to be a self-sustaining system. It seems like if we can't figure out how to do it here, we have no chance to do it on the Moon or Mars. Mars is cool as a story but we don't have our sh!t together enough to really try.

It's another planet, you could suddenly create your own country. It's a billionaire's dream.

I like the idea, are there any benefits from starting under ground or could we just do it even cheaper on the surface?

I think some benefits are difficulty (we want to stress test), similarity (we probably build underground on Mars), and a whole lot fewer outside influences (a lot fewer organisms underground).

It's a good question, the whole "Biosphere" project which you can go visit in Arizona which sought to do something like this. It isn't underground, there really isn't much advantage, and there is a whole lot of expense, in building under ground.

So the partial answer is that people are doing this research. Complex interactive systems like this however are very hard to design all at once. One strategy might be to solve individual problems like having a habitat that provides all of its own oxygen and CO2 processing. Then once that is understood have one that can recycle 100% of bio-waste. Then add a long term power supply, then figure out how to make that supply a renewable one. It is a very complex process and each step will reveal new interconnections that need to be dealt with.

If the Biosphere project taught us anything it's there is a huge amount of problems that wouldn't transfer into other environments, and those other environments will also create tons of different nontransferable problems.

While the famous experiment is over, they've not stopped entirely. Three months ago [0], they announced they'd reopen a small portion of it to investigate how they can winnow down from scrubbers to plant based oxygen replenishment.

[0] https://news.ycombinator.com/item?id=28443187

Because that's boring. Once Mars colonies become a real possibility, obviously the missions will be tested on earth before we yeet billions of dollars to another planet and hope it all works. But going through all that work and money solely for the purpose of an Earth bound terrarium is boring. Who would want to pay for that?

Not only is it a profound and fundamental capability if we intend to live off-planet, it's basically the only relevant capacity, conceived broadly (how to manufacture the means for indefinite survival given supplies of matter and energy). It's the universal constructor problem and our present solutions are fragile and primitive. There is virtually infinite room for improvement. How is that boring?

could be useful in case of disasters, if we ever have to bunker up for a long time

You’ve got it right here. If life’s ultimate purpose is to grow, we have a whole solar system we can grow into. Once we solve growth on planet two, we will be vastly closer to other planets, moons, asteroids and habitats. There’s a whole lot of energy and materials right here at this star and a whole lot of real estate that doesn’t require an environmental impact statement. Per aspera ad astra.

regardless of questions of growth or ultimate purpose we need to be able to do this if we want to persist for any significant length of time in any habitat, planetary or otherwise

a truly sustainable civilization can successfully manage its planetary (or ship- or station-borne) ecology and protect itself from threats with advanced technology equally well, and we are wildly immature in both capacities

i think youre putting the cart before the horse here. there is no possibility of a Mars colony without this work happening on earth.

>> obviously the missions will be tested on earth before we yeet billions of dollars to another planet and hope it all works.

That's my whole point. This work is only interesting as a precursor to doing it on another planet. Nobody has any motivation to do the work and spend the money without a direct connection to transferring it to another planet.

Whenever someone says "why don't we just do it on earth first??". We will: but only as the testing phase of an actual mars colony mission.

were we not actively making this planet more difficult to live on I would be a bit more likely to agree but even so there seems to be plenty of motivation

do we not want to be resilient to e.g. solar flares, supervolcanoes, asteroid impacts/nukes/tungsten rods dropped from orbit, on Earth or Mars or anywhere

See the CHAPEA and HERA campaigns

I can tell no one here has any real awareness of the real science literature written on the subject. We are building, testing, and designing things like this all the time. Just in smaller increments. Just last year I met a young scientist who was working on a research base in Antarctica doing various biology studies on plants/animals living in low-light sealed environments... I was headed to the North Pole and she the South.

I know a one-to-one experiment has a grandiose appeal, but NASA and all sorts of other institutions work on this problem in minor steps every day. The step just aren't, on their own, media worthy or very sci-fi-ish. Heck. Antarctic bases and the ISS, and many other science ventures are essentially a testing ground for some of these things on their own.

Thanks for the comment, this is very helpful. Apart from the first sentence.

My apologies if it's condescending, that's not my intent. I wanted to point out that there's a lot of large wild hairs being thrown around, that's all.

You seem to be assuming that a base on Mars or the Moon would have to be a closed system but that is not true.

There are plenty of useful materials on a planetary surface, for example water. There are also many ways to take advantage of a CO2 atmosphere or oxygen from lunar rocks.

Even space stations don't need to be fully closed, for example the ISS is constantly being resupplied.

Archived version: https://archive.ph/unuNw

Every 5 or 6 years since I was born, NASA has discovered water on Mars. I was predicting they would discover water on Mars back in 2020, but I think COVID clearly slowed them down this time.

Is this canyon anywhere near our rovers?

EDIT: looked it up, they're basically on the opposite sides of the planet

Water: https://geohack.toolforge.org/geohack.php?pagename=Water&par...

Perseverance rover: https://geohack.toolforge.org/geohack.php?pagename=Persevera...

No, and Valles Marineris is about 7km deep in places vs the Grand Canyon's 1.8km max depth, not something a rover could go check out.

Robert Zubrin actually uses Valles Marineris as part of the plot in his work of fiction First Landing that lays out how a manned mission to Mars might go.

But a helicopter could. :-)

exactly, and in the newfound current era of pinpoint orbit-to-surface landings you might just send a rover too.

I'm imagining a future where space colonization is just robots fighting it out / eachother.

You would love to read the Corporation Wars trilogy https://www.amazon.com/Corporation-Wars-Trilogy-Ken-MacLeod-...

I want a movie about that :)

Also mentioned in the Expanse book series as region which was colonized by Texans (IIRC) so they have that nice accent.

Direct link to paper:

[0] https://www.sciencedirect.com/science/article/pii/S001910352...

Archived version of the original paper: https://archive.ph/unuNw

So, we ship our carbon to Mars, which warms it up while solving our climate problem. Once it's warm enough, that water can exist on the surface, setting it up for terraforming.

Now that I've solved all that, I think I'll knock off early for the weekend.

Great job, thank you for your contribution to mankind! :)

I'm an idea man. I link up with implementers, and then we share the money.

Not even qualified to solve this, but there are several ways to capture carbon:

https://en.m.wikipedia.org/wiki/Carbon_capture_and_storage

Not enough carbon, that said somehow siphoning CO2 from Venus turning it into dry ice and using a mass driver to shoot it at mars whilst completely nuts and well beyond our technological reach might actually work.

It would also be a 2 for 1 terraforming effort. Then the only thing you need to do is figure out how to spin Venus to break the tidal lock. And if you set up your mass drivers correctly you should be able to give it some additional spin at least.

I swear in my life time we've discovered water in Mars about 8 times now.

That's because (newsflash) there's water on Mars!

Question is when will someone invest in a mission for something that actually does something with it that is not measuring its existence with remote sensors.

I think the parent is alluding to the fact that this topic keeps being presented to us as news.

There's water here on Earth, too. But we don't keep "discovering" it.

I don’t understand any of these comments. Discover has two meanings. Unexpected or within the course of a search. We discover oil and mineral deposits all the time. We don’t usually say “You discovered more lithium? Big deal. Been done before”

While it may not be mind blowing, each source of water discovered makes some kind of Martian base more feasible so it is of interest to some

If new sources of water don’t interest you, that’s fine. But it is still within the definition of discovery

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