Green

Auroras at the South Pole, from the ground (courtesy of Robert Schwarz) and above from the ISS

So, there has been lots of solar activity the last couple of weeks, which means we’ve been getting some pretty amazing light shows down here. And since the sun is slowly making it’s way towards the horizon, we are also starting to get some reds and purples along with the usual green auroras.

The other place we are getting green is of course the green house, which has been our only source of fresh food since station closing back in February. It is also a great place to just hang out. It is warm and bright and humid and has actual smells, unlike the rest of the station, which tends to be a little chilly, a little dark and very dry (relative humidity is usually in the single digits).

Our green house is run by the University of Arizona, which is the same institution that is developing greenhouses for a possible human settlement on the moon. Since the Antarctic Treaty prohibits bringing soil down here, the plants grown in a hydroponics-system, fed by nutrient rich water. The system is closely monitored, from water, minerals, CO2, and light, to temperature, pH, and humidity, and the outputs, like the weights and types of produce harvested are carefully measured.

The rate at which things grow down here is pretty incredible. In their natural habitat plants do fairly well, but they have to make due with what they have. Down here the plants can be given almost exactly what they need so they grow really well. We could probably make them grow even better if we optimized for a single crop, but since variety is the spice of life, and makes meals more interesting, we have to make compromises. So things like strawberries don’t get as much light as they’d like, which means they don’t grow as fast or as big as they could.

Basil sprouts, among others

Seeds are planted in a sponge-like substrate, which is initially placed on a tray with a thin layer of water on the bottom. As the root system develops, they are moved to troughs that line the green house.

The plants are fed through a complex computer-controlled system of hydraulic system of pumps, mixers, tubes and measurement sensors hidden under the troughs.

Our not very big strawberries

The troughs are built on rails so that different plants can be rolled in and out depending on how much light the various plants need.

We've got lots of lettuce down here

Also, a variety of chard. Very colorful, and tasty.

Our tomatoes have not done very well this winter

But the peppers look very pretty, even if I don't like them