GreenHab Report – January 26th

GreenHab Officer: Scott Dorrington
Environmental control: heater off (space heater on overnight), fan on in afternoon, door closed (open briefly)
Average temperatures:
07:52: 46.8 F, 56%
09:27: 86.7 F, 31% space heater off, light off
10:09: 97.7 F, 20%
10:25: 98.8 F, 17%
10:43: 97.7 F, 17%
11:14: 104.4 F, 16%
11:26: 99.9 F, 12%
11:31: 101.8 F, 14%
12:19: 121.3 F, 10% fan on
12:51: 97.3 F, 11%
13:04: 96.4 F, 11%
13:39: 99.9 F, 10%
13:56: 99.1 F, 10%
14:45: 93.9 F, 10%
15:19: 88.2 F, 11% fan off
16:03: 105.4 F, 14%
16:42: 97.5 F, 17%
18:57: 82.2 F, 21% light on, heater on
Hours of supplemental light: 9.5 hrs (counting from midnight to 9:30am)
Daily water usage for crops: 6 gallons + 0.5 gallons mist
Daily water usage for research and/or other purposes: 0 gallons
Water in Blue Tank (200 gallon capacity): 136 gallons
Time(s) of watering for crops: 9:30 mist, water at 10:30am, water at 13:30, regular misting through the day (at temp log times)
Changes to crops: None
Today was our first sunny day of the mission. The morning visit at 7:50am showed a still chilly temperature of 46.8 F, however I knew from sol 3 that temperatures were likely to climb in the greenhab with the sun out, so planned to diligently monitor the temperatures throughout the day. Today’s music therapy soundtrack was the Eagles, beginning with Tequilla sunrise. I returned to the greenhab at 9:30 to turn off the space heater, and the temperature was a nice 88 F. It was very sunny in the greenhab, made a note to bring sunnies upon return. I returned at 10am to find temperatures up around 97 F. From googling during comms window last night, I found that tomatoes like a temperature around 70 to 90 F, so wanted to keep the temperatures below 100 F through the day. I did some experimenting with opening the greenhab door to try to cool temperatures. This did manage to drop the temperature a few degrees in 15 minutes, but I also noted that this also dropped the humidity (likely from the dry desert air). I tried closing the door and giving a decent misting of the plants, which seemed to raise humidity a bit, but temperatures were increasing again. I decided misting alone was not good enough to raise humidity, so commenced with a morning watering. Rather than give one large watering as done in previous sols, I decided to do 2 gallons at this time, and return for another watering later in the day. I noticed that this prevented much of the water drainage from the tomato plants I was seeing in previous sols. I aim to continue this twice daily watering as I think it will help with water conservation, and might prevent over-soaking the tomato roots. While watering, with the door closed, I monitored the temperatures rising again. I tried this time with the fan, and noted temperatures dropping from 106 to 100 F in a few minutes. But humidity also dropped again. I turned off the fans, and the humidity increased after a few minutes (likely from water evaporating). I returned to the hab, leaving the fan off. I checked back in 50 minutes later to find the temperature had reached 120 F. I turned on the fan again, which quickly brought temperatures back down to 100 F. I also raised the mesh shade cloth on the south wall of the greenhab to try to block some of the heat coming in. The tomatoes were also moved in off the wall during this stage. I left the fan on for much of the afternoon, setting myself alarms to return at regular half hour intervals. The temperatures were consistently in the 90s, and gave regular mistings on each visit. At 1:30pm, I gave another watering of 3 gallons. At this time I also noticed tomato #7 has a fruit that is beginning to turn yellow! This was a welcome surprise, as tomato #7 was looking smaller than the others from the start of our mission. The tomatoes were shuffled around throughout the day to keep them out of direct sunlight. Temperatures remained in the 90s for the next few visits. At 3.20, I found the temperature at 88, and decided to leave the fan off for a bit to try raise the temperature before the sun started setting in the afternoon. In the afternoon, Mission Support radioed confirming delivery of replacement parts for the heater. The heater was fixed, so we should expect some more comfortable overnight temperatures for the plants.
Harvest: None
Support/supplies needed: None

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