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Payload Name“The Green Machine”ISS Increment __ 30-Day Post-Flight Operational ReportPrincipal Investigator and Affiliation: Joel Bertelsen – Chatfield Senior High SchoolApproved by:Approved by:Approved by:Approved by:IntroductionObjectives of InvestigationThe experiment was designed to study the viability of algal hydrogen production in space. During the course of developing the experiment a secondary objective was added to determine if a second algal species, one that stores lipids that could be used as biofuel precursors, would be able to produce lipids in space. In specific, our aim was to demonstrate that algae removed from the gravitational influence of the Earth would still produce the end products desirable for fuel, namely hydrogen and lipids. Previous Mission ExperienceNone Background/History of ProjectThe idea for the experiment came from research being conducted at the National Renewable Energy Laboratories. Researchers there have been able to produce hydrogen in sulfur deprived environments using the alga Chlamydomonas reinhardtii. In addition, the alga Chlorella vulgaris has been shown to produce lipids when deprived of nitrate, creating a precursor to biofuel. Methods/Research OperationsDiscussion of Method/ProtocolChlamydomonas reinhardtii: This species has been shown to produce hydrogen when deprived of sulfate in anaerobic conditions. The production of hydrogen happens fairly quickly once the solution becomes anaerobic, creating a design challenge. In order to delay the onset of hydrogen production until orbit is achieved, a small volume of magnesium sulfate is added to the sulfate free media (TAP-S). The preflight molarity of the media is 0.04 M MgSO4. With this small addition of sulfate, hydrogen production is delayed for several days. To detect the production of hydrogen on orbit a hydrogen sensing tape is used and placed in solution with the algae. Upon exposure to hydrogen the tape turns color from a light tan to a gray color. Chlorella vulgaris: This species has been shown to store lipids during periods of nitrate stress. In order to produce the conditions necessary for lipid production, the algae is removed from the nitrate rich media in which it was grown, and rinsed to remove the nitrate from the solution. The alga is then resuspended in a nitrate free solution of Bold’s Basal Media. Detection of lipid production is measured by post flight analysis. Flight Operation SummaryPre-flightTwo weeks prior to flight, new cultures of both algal species are inoculated into their respective media – TrisAcetate Phosphate (TAP) for Chlamydomonas reinhardtii and Bold’s Basal Media (BBM) for the Chlorella vulgaris, and grown within 1 liter bioreactors with room air bubbled through the solutions. 2 days prior to launch, the two species were prepared for flight. Chlamydomonas reinhardtii: 100 ml of algal solution were pipetted from the culture and spun to remove the TAP. The cells were rinsed twice in TAP-S to remove residual sulfate. The algae were then resuspended in 26 ml of TAP-S (sulfate free TAP) in the bioreactor with 2.1 ml of 0.5 M magnesium sulfate added to bring the final molar concentration of sulfate to 0.04 M in order to delay the onset of hydrogen production until installation on station. This was repeated for a second section of the bioreactor. Chlorella vulgaris: 45 ml of Chlorella vulgaris were drawn from the culture and spun to remove the nitrate. The pellet was then resuspended, vortexed to break up the pellet and triple rinsed using nitrate free BBM to remove as much nitrate as possible. The pellet was vortexed one last time and suspended in 8 ml of nitrate free BBM. This was repeated for a second section of the bioreactor. In addition to the chlorella that was rinsed and loaded for flight, samples were collected and frozen to establish a baseline for lipid content.In-flightUp arrival at station, the module was connected to power and allowed to run for 24 days. No special treatment was necessary until the end of the 24 day period. Before loading for the return journey, the module was frozen to prevent the Chlorella vulgaris from consuming the lipids that it had produced. Post-flightUpon return, the pictures taken while on orbit were analyzed to determine when and if hydrogen was produced on orbit. In addition, the Chlorella vulgaris chambers from the bioreactor were drained and analyzed by NREL for lipid content. List of Pre-flight, In-flight and/or Post-flight AnomaliesPreflight: No preflight loading anomalies were noted. Launch was scheduled for June 1 and preflight loading procedures were conducted with a launch-48 hours window in mind. Due to weather conditions at KSC the flight was delayed until June 3. The decision was made to leave the bioreactor in cold stow and not repack for the second launch attempt. The module remained in cold-stow at 4°C for two more days. No other anomalies are known.In-flight: The camera experienced some change in focus during launch, causing the in-flight pictures to be slightly out of focus and off center. In addition, the camera failed to record pictures for the entire 24-day period for unknown reasons. This is not a critical failure since the initial photos indicate that no hydrogen had been produced in chamber 1 upon power-up on station, and upon post-flight analysis, chamber 1’s hydrogen sensing tape showed clear signs of hydrogen production.Post-flight: None are knownData Analysis and ResultsChlamydomonas reinhardtii: Image 1 (next page) shows one of the first images taken after the module received power. Chambers one and three (left and right) contained Chlamydomonas reinhardtii, and the hydrogen sensing tape in chamber 3 is clearly seen to be gray. This indicates that hydrogen was already present at power-up and no conclusion can be drawn regarding when the gas was produced. In chamber 1, however, the tape is clearly seen to be tan in color upon power-up on station. This indicates that there was no hydrogen present upon arrival on the station. Upon receipt of the module for post-flight analysis, the solutions were removed and the tape inspected for signs of hydrogen production. In Image 2, the tape is seen through the polycarbonate cover, just as in image 1. In this image the tape shows clear signs of hydrogen production, indicating that hydrogen was generated on orbit. Image 3 shows the back of the polycarbonate cover and in this image the gray color is even more apparent. In image 2 and 3 the gray tape in chamber 3 is seen more clearly, in agreement with the images from orbit. Why the hydrogen was produced early in this chamber is not known. Perhaps the sulfate concentration in this chamber was not adequate to suppress hydrogen production for long enough or some other factor that accelerated the production of the hydrogen. The solution from this chamber was not analyzed to compare with chamber 1, as funding was not available for this. In addition, the redundancy was purposeful to provide a backup in the event of an anomaly. Image 1 12490451098550016192530162500350520030734000 Image 2 Image 3Chlorella vulgaris: Looking again at Image 1 above, the Chlorella vulgaris was loaded into chambers 2 and 4 (above and below in the photo). The color of the algae in chamber 2 can be seen to have a yellowish-brown hue. This is indicative of lipid production and suggests that upon power up on station, the algae had already produced some lipid content. In Image 3 on the next page, chamber 4 can be more clearly seen on the left, and the same yellowish-brown hue can also be seen in this photo. The results from NREL indicate that the post flight lipid content were the same or less than preflight levels, indicating that if lipids were generated on orbit, none remained upon return to Earth. The evaluation by the researchers at NREL suggests that the algae likely consumed any lipids that were generated before the post flight analysis could be made. 145796025146000 Image 3Lessons Learned/What I Wish I’d Known When I StartedThe CASIS experience for me has been an amazing journey of insight. My degree is in engineering, but to be a part of a project from start to finish has illuminated aspects of the design process that I didn’t appreciate previously. It was great for both my students and me to truly experience the process of design and redesign. In most educational environments, even ones that incorporate projects, you design your project, build it, test it and then move on. If it works – great! If it fails – better luck next time. The common element: you move on. With the Green Machine, moving on wasn’t an option. Not working was not an option. Giving up was not an option. It was a blessing and a curse. As the principle investigator success was on my shoulders and getting my students to come along the challenge. They did an amazing job and came up with a great design through many iterations and many failed attempts. One of the moments that I will never forget came in the briefing room at the OSB-II at KSC. We were manifested on SpaceX-7 and 8 students along with several members of their families, and my family had come for the launch of our algae. As the Falcon flew through the nearly cloudless sky, several of us remained on the deck to watch as long as we could. As the vehicle became too small to see, and after a small puff that I believed was stage separation, I decided to head inside to hear the feed from mission control. As I approached the door one of my students emerged from within the conference room and as I passed him he said it was a non-nominal launch. There was a brief moment when I hoped that he didn’t know what he was saying but as we entered the room it was immediately clear that the vehicle had been lost. I still find it hard to retell the story without becoming emotional… As we gathered and listened to the sparse communication from mission control, we slowly began discussing our project and what had been lost. And in that discussion the most amazing thing happened… my students began discussing things that they wanted to change about our design. Within 15 minutes of losing all of our work they were back at work in redesign! They had truly come to embrace the process of design and had learned to live the words of Henry Ford that “failure is simply the opportunity to begin again, this time more intelligently.” What was equally impressive, at the end of the summer, several students came back to school before leaving for college to make design changes to our bioreactor to prevent leaking during the loading process. In addition to my thoughts on the design process, I have come to understand the role of testing in a new light. This again comes from being involved in the whole project from start to finish. It has instructed the work that I continue to do in my engineering class –something that I knew before but truly experienced during the CASIS project. It’s like looking outside on a winter’s day – you know it’s cold out there, but in a cerebral sort of way. When you find yourself standing in the snow without a hat, however, you know you should have made a pre-flight check list! And you should have tested your hat in more varied conditions to know for certain that it would perform when you needed it. Fortunately we didn’t have any major failures in our design. I joke with my students when discussing space flight that the number 1 rule of rockets is ‘pointy end up,’ and that the number 2 rule is ‘always bring a spare!’ It is fortunate that we planned some redundancy in our design – chamber 1 in our bioreactor – and that this little wedge of algae worked to confirm the wisdom of rule #2!Finally, I think it is good that I didn’t know how much work this project would take. I’m not sure I would have jumped if I knew how far it was to the bottom! I’m glad that I jumped and I know that my students continue to benefit from my experience. Just this afternoon as I finalized work on this report I showed the pictures from the bioreactor to my physics students, showing them clearly that hydrogen had been produced and that it had happened on station. It was a special moment as they realized that they were looking at evidence of the first (that I could find…) time hydrogen had been produced photosynthetically in space. Another special moment for me came as I tried to confirm my claim form the last sentence, that The Green Machine was first. I googled it. We were 8th on the list. I’m not sure what to do with that… but I’m emotional once again and humbled to have been given the opportunity to participate in the NDC and to be selected to fly, not just once but twice!! I tell people that just seeing a launch is a special honor – not many on the planet have been to the OSB-II. It was on my bucket list – and in that incarnation I didn’t have payload aboard!! I then joke that to be there for a non-nominal launch is even rarer. To get a second chance to fly and to see it from the parking lot of the VAB (thanks Bill and April!) – now we’re getting somewhere. To be the first to produce algal hydrogen in space… wow. ................
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