
Study: Potatoes can grow on Mars - Mz
http://www.upi.com/Science_News/2017/03/08/Study-Potatoes-can-grow-on-Mars/7961488992637/
======
david-given
From the article:

"The box mimics the day-night patterns of Mars, as well as its temperature,
air pressure and atmospheric composition."

Wait, really? They're growing plants in what's practically a vacuum and at
subzero temperatures? _Really?_ That seems... stupendously unlikely... to me.
Not that I wouldn't love to be wrong, mind.

Anyone have a link to actual data? Everything linked to is just press fluff.

 _Update:_ Actual articles on growing plants at very low pressure:

[https://science.nasa.gov/science-news/science-at-
nasa/2004/2...](https://science.nasa.gov/science-news/science-at-
nasa/2004/25feb_greenhouses/) \--- at 1/10 of an atmosphere, plants' metabolic
balance gets screwed up and they go into drought response and die, no matter
how much water is actually available.

[http://online.liebertpub.com/doi/abs/10.1089/ast.2009.0362](http://online.liebertpub.com/doi/abs/10.1089/ast.2009.0362)
\--- but lichen's probably fine.

~~~
clinton
I ran a similar experiment at home, albeit with a fern rather than potatoes
and without simulating martian light.

My fern started to perish (and it was a well established plant). The biggest
problem I'm facing at the moment is that Mars is extremely nitrogen deficient.

[https://reprage.com/post/marsarium-9](https://reprage.com/post/marsarium-9)

[https://www.reddit.com/r/Colonizemars/comments/5vi52v/inspir...](https://www.reddit.com/r/Colonizemars/comments/5vi52v/inspired_by_rspacex_i_made_a_marsarium_to/)

~~~
Terr_
That reminds me of an Asimov story, "Founding Father", involving ecosystem
change on a planet by stranded astronauts.

~~~
clinton
Best places to find a copy these days?

~~~
omgam
Any central public library is fully stocked on Asimov.

~~~
clinton
It seems that this short story was originally published in an old science
fiction magazine (that my local library doesn't stock). Was wondering if it
also made its way into a compilation of some sort. Google hasn't turned up
anything for me yet.

~~~
cmdr2
Is this the story? [http://www.young-adult-books.com/read/buy-jupiter-and-
other-...](http://www.young-adult-books.com/read/buy-jupiter-and-other-
stories-926/22882) (link says "buy", but looks like the entire story is on
that page)

~~~
logicallee
Can you imagine if someone told Asimov that his story "Buy Jupiter" would be
mistaken for a "link" to buy a copy of his work, by someone reading on an
international network of computers that have access to all of the information
in the world - and were so overrun with advertising that his own title was
mistaken for one. Given "Buy Jupiter's" plot summary -
[https://en.wikipedia.org/wiki/Buy_Jupiter](https://en.wikipedia.org/wiki/Buy_Jupiter)
[1] - this is extremely apropos!! Some things never change :)

[1] WHICH I'M LINKING ON A FREAKING ENCYCLOPEDIA GALACTICA THAT CONTAINS IN
EVERY LANGUAGE ALL OF THE GENERAL KNOWLEDGE OF THE WORLD (WIKIPEDIA).

------
guelo
I think this article is wrong about the temperature. There is little
information available but here is the original press release
[http://cipotato.org/press-room/blog/indicators-show-
potatoes...](http://cipotato.org/press-room/blog/indicators-show-potatoes-can-
grow-mars/)

From what I can gather they used soil from some Peruvian desert and increased
the CO2 in the chamber. But there is no mention of simulating the -80F night
temperatures typical on Mars.

~~~
Shorel
I'm pretty sure Martians measure temperature in Celsius.

~~~
ars
Celsius is equally arbitrary to Fahrenheit.

No, Martians measure in Nano Yocto Planck Degrees above Absolute Zero, I
hereby dub that unit the Plancktigrade.

~~~
astrodust
Celsius at least has a family of units that mesh with it precisely. To heat
one cubic centimetre of water up 1°C takes 1 Joule. It also essentially weighs
1 gram at normal temperatures.

How many BTUs does it take to heat up one cubic foot of water by one degree
Fahrenheit?

~~~
freeone3000
It takes one BTU to heat one pound of water, one pint, one degree Fahrenheit.

The units may be arbitrary, but they still line up.

~~~
astrodust
Yeah, but a pound of water is not a cubic foot. A pint has nothing to do with
inches.

~~~
ars
That has nothing to do with temperature.

You can keep metric and use Fahrenheit with very little change.

And you got your units wrong anyway: "To heat one cubic centimetre of water up
1°C takes 1 Joule" \- you mean 1 calorie, not 1 Joule.

Change Celsius to Fahrenheit and only calorie changes, and since it's anyway
not part of SI it makes little difference.

Joule is the main energy unit, and it's not tied to Celsius at all.

I totally get the arguments for metric - except for temperature. For
temperature Fahrenheit is the better scale.

Look here:
[https://en.wikipedia.org/wiki/International_System_of_Units#...](https://en.wikipedia.org/wiki/International_System_of_Units#/media/File:SI_base_unit.svg)

And notice how Kelvin stands alone - it's not tied to any other unit. It can
be replaced with almost no impact.

~~~
astrodust
Ah, you're right about calorie vs. Joule. That is a bit rough around the
edges.

> For temperature Fahrenheit is the better scale.

Yeah, no. It's a stupid system. It's not even calibrated properly. 100° was
supposed to be body temperature. They got it wrong. 0° was the lowest
temperature they could measure at the time because that's when mercury froze.
That's so useful! I really want to know if the mercury I carry around all the
time is going to freeze outside.

Meanwhile °C is simple: 0°C is "watch for ice" and 100°C is "water boils"
(minus altitude factor).

I don't know how you can praise Kelvin and slam Celsius since they're the same
"size", it's just that the zero point of Kelvin was set to absolute zero
instead of the freezing point of water. °C = °K + 273.15. That's it.

~~~
ars
> That is a bit rough around the edges.

Correct. It would be one thing if Celsius is somehow tied into the rest of the
SI units, but it is not, which means we can replace it.

> It's not even calibrated properly.

Who cares if they got the calibration of Fahrenheit wrong, at the end of the
day it's more usable than Celsius for humans.

0 Fahrenheit is the temperature when it's really cold outside, 100 is when
it's hot. It doesn't get simpler than that. If you are outside those ranges
you need to take special precautions. No, I don't care about mercury either,
but I do care to know when it's cold.

It's not that hard to remember 32 for ice. With Celsius you need to deal with
negative temperatures all the time, and worse, the size of the degrees is too
coarse.

> 100°C is "water boils"

And exactly how often do you need to measure the temperature when water boils?
Probably about as often as I freeze mercury. So 100 is a very useless range on
Celsius - you are using your "best" numerical range on useless temperatures.

On the other hand it's quite common to want to know when it's hot enough that
you will sweat. Above 100 (body temperature) you will sweat.

Labs and Ovens don't really care about which exact unit, so let them deal with
the higher (or lower) numbers - the only time it matters is for ordinary
humans checking the weather.

> I don't know how you can praise Kelvin and slam Celsius

You misread, I did not praise Kelvin, I said we could replace it.

~~~
astrodust
> It's not that hard to remember 32 for ice. With Celsius you need to deal
> with negative temperatures all the time, and worse, the size of the degrees
> is too coarse.

Well, the whole world manages to deal with °C and only America and a handful
of backwater countries insist on using °F.

"Too coarse" is absurd. People just measure to the nearest 0.5°C if you want
to get all fussy, but that's not normally the case. It's 12° out? Wear a
jacket. 12.0 vs. 12.5° isn't going to change that.

It keeps the numbers smaller. Temperatures here flop between -40°C and +40°C,
so the numbers never get large. Meanwhile in the US you see temperatures of
100°F all the time as well as negative ones like -30°F. It's a much wider
spread for no real reason.

I hope you know the only reason America didn't get with the program and
metricize like it was fully intending to do in the early 1980s is because
Reagan was an asshole.

~~~
ars
I'm onboard for metric - just not for temperature.

Just because you manage to deal with C doesn't make it better.

Do you see the parallels? You tell Americans all the benefits of metric, they
don't care. You tell Europeans all the benefits of Fahrenheit, they don't
care.

People don't want to change.

> It keeps the numbers smaller.

No, it doesn't. You need 3 digits since you need the decimal (-20.5).

~~~
mhenr18
It's more that you can't tell the difference between 30C and 30.5C. No one
_ever_ forecasts temperatures using decimal degrees here in Australia.

You only need decimals for highly accurate measurements, but at that point
you'd need decimals for Farenheit as well.

> You tell Europeans

Erm, how about the rest of the world?

~~~
dvtv75
Judging by the title of this thread, I think the GP meant to type Europans,
not Europeans.

------
donpdonp
I know, I saw Matt Daemon grow potatoes on Mars in an in-flight documentary
called "The Martian".

~~~
pklausler
/sbin/mattd

~~~
Waterluvian
Can I get in on the joke? :)

~~~
tarmstrong
They're making a joke about the misspelling of Matt Damon. "Daemon" is a
computing term [0] and /sbin/ is a folder that you might want to put a Matt
Daemon in. (Also, daemons are often named with a "d" at the end, like "etcd"
or "mattd".)

[0]
[https://en.wikipedia.org/wiki/Daemon_(computing)](https://en.wikipedia.org/wiki/Daemon_\(computing\))

------
azernik
Why exactly did this experiment require a satellite? For biological purposes
Martian gravity is probably closer to Earth gravity than to microgravity, and
all the other conditions could be reproduced for cheaper and at larger scale
in a ground laboratory.

This smells of a publicity stunt to me.

~~~
AdamTReineke
From the photo, I'm pretty sure the CubeSat is on the ground.
[http://nkxms1019hx1xmtstxk3k9sko.wpengine.netdna-
cdn.com/wp-...](http://nkxms1019hx1xmtstxk3k9sko.wpengine.netdna-cdn.com/wp-
content/uploads/2017/03/CubeSat.jpg)

The photo is from their press release: [http://cipotato.org/press-
room/blog/indicators-show-potatoes...](http://cipotato.org/press-
room/blog/indicators-show-potatoes-can-grow-mars/)

~~~
maxander
Isn't a cubesat on the ground called... a box?

There's no mention of a past or future launch in the article, so this looks
like an egregious case of buzzwording.

------
u801e
They didn't mention whether they tried to simulate the radiation levels plants
would experience on Mars in their experiment. I don't know whether that would
change the results.

~~~
JohnJamesRambo
[https://www.newscientist.com/article/dn22520-mars-is-safe-
fr...](https://www.newscientist.com/article/dn22520-mars-is-safe-from-
radiation-but-the-trip-there-isnt/)

I didn't know the answer so I googled it. Apparently it isn't that high.

"Readings from NASA’s Curiosity rover suggest radiation levels on the Red
Planet are about the same as those in low Earth orbit, where astronauts hang
out for months on the International Space Station."

~~~
_rpd
> radiation levels on the Red Planet are about the same as those in low Earth
> orbit

... which coincidentally is where the experimental potatoes in the article
were grown.

~~~
simonh
Unfortunately not, looks like they never got round to launching the cubesat.

------
nsxwolf
"Scientists with the International Potato Center" made my day.

~~~
Deestan
Soon "potato scientist" will be as impressive as - if not more than - "rocket
scientist".

~~~
dvtv75
Second post on this thread, and sadly it's as much a joke as the first.

From this point on, I'm going to cease saying "it's not rocket science," and
start saying "...it's not potato science."

------
kumarski
Important to understand this doesn't mean potatoes can grow in perchlorate
soil.

------
Tepix
Here's a relevant related link:

[https://www.reddit.com/r/Mars/comments/4ib9d9/never_freezing...](https://www.reddit.com/r/Mars/comments/4ib9d9/never_freezing_passive_martian_greenhouse_no/)

The post introduces a model of a passive (pressurized) greenhouse on Mars that
manages moderate temperatures just using insulation and some soil and water
for thermal inertia.

------
EGreg
But can they grow in Martian soil? Its regolith is missing crucial nutrients,
methinks. Otherwise, wow! The Martian's premise might actually be realistic!

~~~
_rpd
It's possible to grow potatoes hydroponically, so growing them in unprocessed
Martian regolith is unlikely to be important until the number of Martians hits
six figures.

~~~
EGreg
So you're going to bring your own soil everywhere? That's the unsustainable
part. Terraforming would take thousands of years.

~~~
nikdaheratik
Hydroponically means "using water as a medium", so not bringing your own soil
and depending on whether there's water available on Mars. You would still need
to put nutrients in the water, but it would be a path to take until you get
composting working.

~~~
_rpd
> depending on whether there's water available on Mars

Actually, we've recently confirmed that there are at least five million cubic
kilometers of water ice on Mars ...

[https://en.wikipedia.org/wiki/Water_on_Mars](https://en.wikipedia.org/wiki/Water_on_Mars)

[https://en.wikipedia.org/wiki/Water_on_Mars#Present_water_ic...](https://en.wikipedia.org/wiki/Water_on_Mars#Present_water_ice)

------
wallace_f
If _anything_ can be grown on Martian soil--whether substantially nutritive or
not--that can self-sustain and propagate on its own, I wonder if that is an
avenue for terraformation.

------
grondilu
> It was a pleasant surprise to see that potatoes we've bred to tolerate
> abiotic stress were able to produce tubers in this soil,

Did they really produce tubers? That'd be impressive, but the video only shows
"initial plant growth".

------
petrikapu
On video there were liquid water. I didn't know such exist in mars.

~~~
pavel_lishin
Potatoes don't exist on Mars, either. But if we're going there, and bringing
potatoes, we'll either be bringing water, or distilling it there.

~~~
_rpd
> we'll either be bringing water, or distilling it there

Probably just melting some of the more than five million cubic kilometers of
water ice that has been identified at or near the surface of modern Mars ...

[https://en.wikipedia.org/wiki/Water_on_Mars](https://en.wikipedia.org/wiki/Water_on_Mars)

------
wollstonecraft
No mention of perchlorate.

------
CalRobert
"CubeSat indicator experiments prove potatoes can grow on Mars. "

That's a pretty flagrant abuse of the word "prove". "Suggests" would be a
better choice.

------
hossbeast
But how do they simulate Martian gravity?

~~~
CobrastanJorji
The box full of potatoes is falling from a great height with a fairly large
parachute? That wouldn't really give the potatoes a very long time to
demonstrate growth, though.

~~~
disconcision
just enough time for them to think "oh no, not again" really

------
dnautics
I imagine one of the biggest challenges is removal of perchlorate salts from
the regolith.

------
nikosdabizas
Hey guys, I helped build the Cubesat, any questions - Fire away!

~~~
TeeWEE
What was the atmospheric pressure during the tests? Martian like?

~~~
nikosdabizas
It is about 40% of Earth's pressure. So low, but not as low as the actual
pressure on Mars, which is too low to even consider. This assumes a greenhouse
environment but without the necessity to create exact earth pressure, making
it easier to maintain, using less energy.

------
nikosdabizas
Hi guys, I helped build the Cubesat. Any questions: Fire away!

~~~
rmeertens
Hey! Great that you answer questions. A question I had was if you took the
temperature into account in your experiments.

A second question I has was: how similar is the sand you are using to real
martian sand?

Do you have any images of the resulting potatoes? Would they be edible?

~~~
nikosdabizas
So, we are regulating temperature in the cubesat. We're assuming the best
conditions possible on Mars, which is summer near the equator. This means up
to 20°C during the day and around zero at night (if you watch the timelapse
you can occasionally see the humidity freeze and defrost, dripping on the
soil)

------
tenaciousDaniel
"If we can't get them out, we'll feed them out." \- King Edward I, Braveheart

------
thatgerhard
well duh, matt damon did it :P

------
agconti
is that you Mark Watney?

------
DoodleBuggy
Hey, I read that book too.

------
vacri
Potatoes on Mars? Poland _can_ into space!

~~~
simonh
And Latvia! Except once on Mars we find potato is rock halucinated as potato
due to starve.

------
personjerry
That headline is not true.

Because we don't actually have potatoes growing on Mars, there is a lot of
information we could potentially be missing, like microbes we haven't
discovered, effects of the radiation and little atmosphere, or (going for an
extreme example here) a rabbit-like creature that we have never been able to
detect yet, that eats the potatoes while we're not watching.

What we've accomplished with this experiment is only to "Grow potatoes in the
closest approximation to Mars setting that some scientists thought of".

