The GreenHab is a massive greenhouse. I made sure the crops in there were healthy and growing. When people really go to Mars, they will have to grow a lot of their own food. That's because it would be too challenging and expensive to bring enough food for the entire mission. It can take up to 300 days just to reach Mars!
I watered the plants in the GreenHab every day. I also checked the temperature and humidity of the greenhouse. Sometimes I trimmed plants, fertilized them, or moved them so they wouldn't get too crowded. During the mission, we harvested tomatoes, lettuce, and herbs. The fresh veggies were a nice addition to the freeze-dried food we had packed.
I wrote daily reports on the GreenHab's status. These were for Mission Control back on Earth. This was probably one of the most important parts of the job. If you think writing essays in class will never come in handy, think again!
I also performed a science experiment. NASA engineers had created a handheld device to detect chlorophyll, a substance in green plants. It's highly unlikely that there are green plants on Mars. But NASA wanted me to test if the detector worked when the operator is wearing an astronaut suit. The result: It worked! But using the detector while wearing gloves was tricky.