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Plants evolved here on Earth, but what if we could take them with us to the stars?
Hey gang, Trace here for DNews with your Weekly Space Update. Last year, NASA announced we'd
found water on Mars, and that got some people thinking... could future astronauts grow crops
in the Martian soil?
It's taken us thousands of years to hone farming on Earth; we could plant crops 'til the cows
come home but what's good for the Earth goose may not be good for the Martian gander. Soil
needs a lot more than water to grow a plant. Soil on Earth contains living and dead organisms
including bacteria and plant matter, rocks and minerals, and nutrients like nitrogen
-- it takes more than 500 years to form an inch of topsoil on Earth. As far as we know,
Mars doesn't have organisms living in its soil to aerate and break down the matter -- so
this is a huge challenge. Not all dirt is created equal, there are 70,000 different
types of soil in the United States alone!
So, to simulate Martian soil we had to gather information about Mars. The Mars Science Laboratory,
Curiosity has been doing JUST THAT, when it wasn't joyriding around Mars and snapping
selfies, of course. Martian soil contains carbon dioxide, oxygen and sulfur compounds
as well as carbonates -- or things that indicate a presence of water. It's about 2% water. NASA gathered soil samples
on Mars and then composed an approximation of Martian soil using the volcanic soil of
Hawaii. From there, plant ecologist Wieger Wamelink planted 14 plants and grew them over
50 days.
Obviously, the plants were given carbon dioxide, oxygen and water, but it's not just the obvious
resources. The seeds of a plant can sustain growth for a while, that's what they're for
-- to help the plant gain a foothold. According to PhysOrg, Wamelink expected the plants to
germinate and then die due to a lack of nutrients. The researchers were surprised to find the
plants did quite well, using the phosphorus and iron oxides to take root.
Unfortunately, the fact the plants grew in a difficult soil environment is only one small
part of the puzzle. The lower gravity and temperature of Mars will make it difficult
for water to be pulled into the soil, and tougher for plants to evaporate their excess
moisture. Plus, the sun is much farther away, so any Martian plants will need extra light.
They're thinking LEDs at the moment, but no one is quite sure.
The moon is much closer, only a few days away. So, to Newt Gingrich's delight, the moon will
probably be the location of Earth's first extraterrestrial colony. Wamelink is also
trying to grow crops in the moon's soil, called regolith. Because our moon has no atmosphere,
the regolith contains mainly meteorite pummeled rock dust, micrometeor debris, rocks and volcanic
glass... Not to mention radiation from the unchecked solar wind.
It would be HUGE if we can manage to get crops to take root in ANY capacity on another planet.
Not only for food, but for oxygen recycling, and to give colonists something to DO all
day. It can get pretty boring to sit around in a spacecraft all the time. But that's...
another story...
And if this doesn't give you the train conductor kick in the head excitement about the future,
how about Shots of Awe with Jason Silva? Watch Jason explore technology, space, human nature
and love. ... Whoa. What does your gut tell you? Are EARTH plants going to grow on the
moon or Mars? Tell us below and subscribe for more DNews! Thanks for tuning in, you
guys are the best.