Marsarium 9, with the fern Lt. Ellen Ripley inside.

So back before Tesla and SpaceX, while Elon Musk was selling off his stake in PayPal he was planning his next move. This was 2001, and Musk was mad keen for humanity to become ‘a multiplanetary species’.

After brainstorming a few things Elon decided he would try and buy a few old Russian intercontinental ballistic missiles… But rather than lobing nukes around the globe, he wanted to strap a glasshouse ontop and lob it at Mars instead. Musk would joke: “You’d have this cool greenhouse on a red background—that’d be the money shot”.

You know. A bit like that movie the Martian. Where our hapless Matt Damon gets his arse stranded on Mars and he has to grow spuds in the Martian regolith. Wait. What? Did I just say regolith? Who the hell do I think I am? Some sort of geologist? DIRT. Matt grows potatoes in the dirt on Mars.

Elon was super serious, he thought a video of healthy green plants growing on mars would be enough to get us dreaming of space exploration again. But the Russians turned him away and while he was flying back to the States, Elon decided he would make his own damn rockets instead.

Now I’m no Internet billionaire and I don’t have the cash to buy missiles or start rocket companies. But maybe I can bring Mars to the plants, maybe I can simulate Mars here on earth? So that’s the project. A marsarium, a little enclosed biosphere with soil and an atmosphere like Mars.

Process / Construction

Starting with an electronics enclosure, Marsarium 9 was made from gas solenoid valves, a pressure sensor and an Intel Edison. Custom circuit boards, relays and gas cylinders where all mounted on plywood and used to mix up a mars like atmopshere of: 96% CO2, 2% Ar and 2% N2.

Homemade Martian soil was made from ingredients sourced from hardware stores and health food vendors. The fern, nicknamed Lt. Ellen Ripley was transplanted into the Marsarium for 30 days.

Results

Lt. Ellen Ripley survived 30 days within the Marsarium, but wasn’t thriving. I doubt she would have lived for another 30 days. The lack of organic matter in the soil was obvious. After the addition of water, the martian soil became very hard. Like a wet, sandy mortar mix that hadn’t completely set. The roots were intact when returning Lt. Ellen Ripley to regular potting mix.

What struck me most about this little project is how Nitrogen deficient it seems on Mars. I definitely should have gone with a ‘green manure’ instead of a fern. Some sort of legume to fix nitrogen into the soil. But even still, I need a much larger Marsarium to have a meaningful amount of nitrogen to play with.

So my Marsarium had about 6.5 litres of volume for the atmosphere. At 2% Nitrogen, 1 earth atmosphere of pressure and about 24°C, that is only about 0.16 grams of Nitrogen. The total available for the fern to use making chlorophyl . That 0.16 grams isn’t going to make much of a dent at improving the 606 grams of the martian soil inside the Marsarium. I probably had more than 0.16 grams of Nitrogen from impurities in the source ingredients.

So I need to scale this up, a intermediate bulk container might be a good (and cheap) next step. That should give me almost 250 grams of nitrogen to play with. It would also be good to add some extra sensors to measure how the atmospheric composition changes over time.

Bill of Materials:

Compressed Gas is really hard to get shipped. Best to find it locally. Carbon Dioxide and Argon are shielding gases used during welding. You can get disposable bottles from hardware stores. I was able to get a disposable bottle of Nitrogen from HVAC and refridgeration suppliers. The disposable bottles have a M10 x 1 thread on top, you will also need regulators to suit. I used these ones.

Source Code:

Credits:

Edits:

  • 2017/03/01 - Added bill of materials, source code and construction video.
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