The observation of the development and growth of plants in a low gravity environment.
A number of seeds were placed in a growth chamber (consisting of a growth media, light source and growth chamber). The development of the (Arabidopsis) plants was observed visually.
Specific characterisation of the growth and health of the plants was provided by regular sampling of the O2 and CO2 levels in the growth chamber. A small amount of stored water was administered periodically to the plants, according to a predetermined schedule, which was compared against ground controls.
A secondary payload was the Field Programmable Gate Array (FPGA). The FPGA was used to analyse the ability of the system to Detect and Recover from Single Event Upset (SEU).
Outcomes from this experiment were looking specifically for differences in health, growth rate and morphology of the developing plants in the reduced gravity and higher radiation environment onboard the ISS. Other variables, such as lighting cycles were also considered in this experiment.
About ICE Cube Service
The ICE Cube Facility is a capable and versatile experiment platform that offers flexibility to host many different experiments in a simple, cost-effective way. A wide community of users can get fast-track access to microgravity through ICE Cubes Service. (http://www.icecubesservice.com/)
The basic size of an Experiment Cube is 1U (10 cm x 10 cm x 10 cm). However, other form factors and customised dimensions are possible. Each Experiment Cube must be developed according to a set of interface and safety requirements specified by ICE Cubes Service.
During flight, users are able to have near real-time telemetry and tele-commanding capabilities with the experiment cube from any location with an internet connection.
ICE Cubes are particularly suited:
1) for raising the Technology Readiness Level (TRL) of components by in-orbit demonstration;
2) for any scientific research related to microgravity or space environment;
3) for STEM education.
ICE Cubes Service has a strategic partnership with ESA and is an accredited implementation partner with the ISS US National Lab that is responsible for operating the U.S. portion of the ISS as one of the national laboratories for use by non-NASA U.S. government agencies, academic institutions, and the private sector.
On 5 December 2018 at 19:16 CET, ISU’s Hydra 1 experiment was launched by a Falcon 9 rocket from Florida onboard a SpaceX Dragon capsule for delivery to the International Space Station (ISS). It was the 16th SpaceX Commercial Resupply Service mission (SpaceX-CRS 16).
Hydra 1 was a 1 kg, 1.25 U cube (125 x 100 x 100 mm) which was installed into the Space Applications Services (SAS) ICE-Cubes Facility (ICF) in the European Space Agency (ESA) Columbus module where it joined two other ISU Hydra payloads (Hydra 2 and Hydra 3) launched in June 2018.
The Hydra 1 experiment hardware consisted of the payload segment and the experimental section.
No additional hardware / AFE was required. Interfaces were solely with the ICE Cubes Facility.
The experiment was controlled through the Raspberry Pi, including:
• Activation of the pumps
• Activation of the camera to take still images
The operation was automatic, although scripts could be modified from the ground through the ICE Cubes FTP server. Images were grouped and downloaded once per day.
• Images were stored on the Raspberry Pi until downloaded.
• Telemetry data were stored on board the cube and downloaded as required. Expected file sizes < 1MB
Hydra 1 featured two main parts: a plant-growth chamber and a control unit. The whole system consisted of water pumps, still camera, sensors, LED array, and a Raspberry Pi unit. The seeds travelled to space inside the plant-growth chamber.
After arrival at the ISS and installation by ESA astronauts, the ICE Cube was activated. The ISU team tested and commissioned the experiment. Once commissioned, the seeds were wetted. The seeds were hydrated using the water supply in the payload. The effect of the water plus the illumination from LEDs caused the germination of the seeds and their growth into plants. One set of plants prepared by UC Berkeley and University of Utah researchers then changed color to indicate a specific protein is being produced. This was regularly observed during the 14 days growth period. Photos were taken by a camera in the payload.
At the end of the growth period the experiment was removed from the ICE Cube Facility and stowed ready for return with the SpaceX CRS-16 mission mid-January 2019 (planned).
After landing and recovery, the experiment was returned to the ISU in February 2019. The remains of the plants were removed and underwent DNA analysis by the team of CNRS researchers affiliated with the University of Strasbourg. The molecules made by the plants were examined to better understand plant metabolism.