Seaweed in Spaaaace!

I imagine that one of the issues with growing plants in microgravity is soil. On Earth, it stays on the ground, but in space it might very well float around.

One way around this dilemma would be to cultivate plants that have no fixed soil requirement. Seaweed, and Dulse in particular fits the bill particularly well. It is a well-known snack food and has been an important source of dietary fiber throughout the centuries.

Dulse is a good source of minerals and vitamins compared with other vegetables, contains all trace elements needed by humans, and has a high protein content. Dulse contains iodine, which prevents goitre. It tastes pretty good too!

It also would be a good way to turn carbon dioxide into a healthy food that could help sustain astronauts.

Appropriate Light Units

Clear plastic sphere (or strong plastic bag)

CO2/Oxygen Unit

Water with proper nutrient mix (perhaps start with some seawater to give it that authentic taste)

Dulse "seedlings"

The basic concept of my seaweed sphere.

The sphere is made from a clear plastic with a light source place above and an oxygenation/carbon uint to provide the proper gaseous needs for the seaweed. There is a "holdfast" in the middle where the dulse can attach - but otherwise it is free to float around.

There is a pressure valve on the top to emit excess gas generated by the seaweed that also doubles as an extraction door and water filter.

When the seaweed is ready to be harvested a second globe is attached. This will automatically cause the water door to open leaving the screen in place. The astronaut then only has to spin the two units to drive the water from the old sphere to the new one. When most of the water is expelled the spheres may be separated and the water filled on placed in the growth chamber to raise new dulse.

The cap on the old sphere is then removed and the dulse in taken out and processed for food - it can even be eaten raw.

In addition to producing oxygen, the dulse also produce a highly food from carbon dioxide within the spacecraft.