Reduced Gravity Flight Experiment
Since Christa McAuliff first proposed the hydroponics experiments of the “Challenger’s Lost Lessons” (1) many new developments have entered the scientific (and educational) arenas. This proposal is designed to directly target two issues noted as problems in Christa McAuliffe’s hydroponics experiment, specifically the substrate and the plant growth rates. We should note that the definition of hydroponics is growing plants in liquid nutrient soil. As further reading in this proposal will explain, we intend to use a “growing gel” but for sake of ease will continue to use the term “hydroponics.”
This experiment will be conducted with Lanette Oliver, Elementary Science Specialist, Judson ISD, San Antonio, Texas and team members from Judson High School FFA (Future Farmers of America).
In Christa’s lost hydroponics lesson she posed the question “Would misting serve equally well as immersing the plants in the fertilizing nutrient solution?” (1) For this experiment we propose testing if plants will grow equally well in a “grow gel” as in a liquid fertilizing nutrient solution and will grow gel be more “flight proof?”
According to the article “Challenger’s Lost Lessons,” a “major problem was that of providing a substrate for the plants to grow while keeping the fertilizer fluid where it belonged.” (1) “ Scientists have now developed gel-like substances that provide the root support and nutrients needed by plants to grow. These gels were originally introduced to help with tissue culture. Tissue culture is a form of plant reproduction in which pieces of plants (as small as one cell) are placed in a special, gel-like growing media full of all the necessary nutrients and hormones needed for growth. In the right environment, the cells will multiply and differentiate to form a new plant. It is a way to produce a lot of new plants from one or even part of one parent plant.” (2) Growing gel is readily available for purchase online from multiple vendors and is relatively inexpensive so that students, teachers, and school campuses can conduct parallel experiments along with the research team. We have contacted Dr. Gary Zeller with Zeller International (3) who is lending advice regarding grow gel options as well as other considerations for roots, etc. It should be further noted that we recognize that simply growing food crops in the grow gel as opposed to the liquid fertilizing nutrient solution will not solve the problem of keeping the substrate where it belongs. Considerable planning is going into the design and build-out of the hydroponics chambers. Design specifications include: liquid tight, low mass, sturdy, clear for light, accessibility to plant and harvest the food crops, reusable, inexpensive, etc. Christa’s chambers used bandage gauze from the drug store. We are researching the possible benefits of use of polyglycolic acid mesh (4)
The “Challenger’s Lost Lessons” article also notes that “The lesson plan called for two white beans to be germinated per day beginning 7 days prior to launching. One plant from each pair would have been selected for flight, contained in its own closed hydroponics system. Several problems emerged. White beans take several days to germinate. They produce large plants quickly after emerging.” (1)This experiment will carry Fast Plants ®. “Fast Plants® are a type of crucifer (a large group of plants that includes mustard, radish, cabbage, and more) that have been bred and selected to have a uniform, short flowering time (14 days) and grow well in a small indoor space, with little soil, under artificial lights. The entire life cycle for Fast Plants® is extremely short, and under ideal growing conditions of continuous light, water, and nutrition, plants will produce harvestable seeds approximately 40 days after planting. Fast Plants® are rapid-cycling Brassica rapa plants that Dr. Paul Williams bred as a research tool that could be used for improving disease resistance of cruciferous plants …. In order to speed up the genetic research in the crucifers, he began breeding Brassica rapa and six related species from the family Cruciferae for shorter life cycles. The end result: petite, quick-growing plants known as Fast Plants®.” (4) Fast Plants® are readily available for purchase online from multiple vendors and are relatively inexpensive so that students, teachers and school campuses can conduct parallel experiments along with the research team . We have contacted researchers Heady Baxter, Paul Williams, and Dan Lauffer at University of Wisconsin who are willing to provide the seeds needed for the research team. We intend to attempt to grow specifically the “Astroplant” and the “Rapid Radish.” Both the “Astroplant” and the “Rapid Radish” will be grown in the “grow gel” substrate. We are researching the size requirements for the “Astroplant” and “Rapid Radish” to produce edible leaves and radish in order to meet with the design engineers for the compartment design. Draft designs using currently available information are in the Equipment Description section below.
While not a problem in the original proposed experiment because growing gel was not used, “ Eventually the plant's roots and top growth will become large enough that it is not practical to use gel to provide the necessary support or nutrients, and at that point, the plants are transplanted into soil.” (2) The choice of “Astroplant” is because its leaves are ready for human consumption as a small plant and we want to see if we can harvest the leaves and have it continue to produce. We will also grow the root crops “Rapid Radish,” and baby carrots that could be harvested for immediate human consumption instead of transplantation into soil.
Judson ISD is the partner for project publicity and dissemination of findings.
Judson High School FFA will partner for growth of test specimens, measuring and recording data, assistance in preparing reports and PowerPoints, assistance in publicity and dissemination of findings.
San Antonio Water System is the partner for assistance with engineer design and build out for the hydroponics chambers and flight compartment apparatus.
University of Wisconsin, Heady Baxter, Paul Williams, and Dan Lauffer will partner for Fast Plants seeds and expertise.
Dr. Dr. Gary Zeller of Zeller International is our partner for expertise with grow gel.
Texas Essential Knowledge and Skills: (6)
Biology “(10) Science concepts. The student knows that, at all levels of nature, living systems are found within other living systems, each with its own boundary and limits. The student is expected to: …
(C) analyze and identify characteristics of plant systems and subsystems.” (6)
Biology “(11) Science concepts. The student knows that organisms maintain homeostasis. The student is expected to: …
(B) investigate and identify how organisms, including humans, respond to external stimuli” (6)
Biology “(13) Science concepts. The student knows the significance of plants in the environment. The student is expected to:
(A) evaluate the significance of structural and physiological adaptations of plants to their environments; and
(B) survey and identify methods of reproduction, growth, and development of various types of plants.” (6)
Test Objectives for Hydroponics:
In Christa’s lost hydroponics lesson she posed the question “Would misting serve equally well as immersing the plants in the fertilizing nutrient solution?” (1) For this experiment we propose testing if plants will grow equally well in a “grow gel” as in a liquid fertilizing nutrient solution.
During microgravity flight we will test integrity of chambers, apparatus, substrate, and plants for both secured and tethered chambers by the use of recording cameras.
Test Description for Hydroponics:
What we will be bringing to Houston.
To Houston we will be bringing three sets of apparatus with hydroponics chambers containing study specimens in substrate.
What we need on the ground.
One apparatus with hydroponics chambers containing study specimens and substrate will stay on the ground.
How we will set up the experiment.
Beginning in the first week of November or earlier, a comparative study will grow:
6 Astroplants in grow gel and 6 Astroplants in liquid fertilizing nutrient solution
6 Rapid Radish in grow gel and 6 Rapid Radish in liquid fertilizing nutrient solution
6 “baby carrots” in grow gel and 6 “baby carrots” in liquid fertilizing nutrient solution
Mass and height data will be collected and recorded daily as well as other pertinent information including harvest dates, etc.
Approximately every 14 days this study will be repeated while incorporating modifications to substrate based on data from previous trials (such as possible use of polyglycolic acid or other mesh for root issues, etc.).
Hydroponics chambers approximately 22cm 3 (based on current information regarding harvest size of Astroplants) will be designed and built with considerations for both flight and growth specifications. Three apparatus will be designed and built that will each hold 2 hydroponics chambers with grow gel substrate and study specimens. Due to space and mass limitations we are choosing to fly only study specimens in grow gel. Each apparatus will carry hydroponics chambers of 1 Astroplant in grow gel and 1 root crop, either Rapid Radish or “baby carrot” (depending on plant success in trials) in grow gel. The two flight apparatus will be equipped with mounted recording cameras.
Approximately 10 days prior to flight (to be based on growth rates from previous studies and best estimate for flight date) the flight group of specimens will be started in the hydroponics chambers they will be flown in. The chambers with their specimens and substrates will be put in the three apparatus and transported to Houston.
What we are doing with it in the aircraft.
In the aircraft we will have one apparatus holding hydroponics chambers with study specimens in substrates that will remain secured throughout the flight. We will have a second apparatus holding hydroponics chambers with study specimens in substrates that will be picked up for a tethered free float during the parabolas. We will have at least one video recording device secured to each hydroponics chamber apparatus. This device will be recording continually during flight.
Steps for conducting the experiment in flight:
We will ensure one set of hydroponic chambers will remain secured throughout the flight and that the other set of chambers will be able to be moved for tethered flight. Additionally we will confirm that recording cameras are ready for recording.
During flight we will start all recording devices. We will monitor that the secured set of chambers stay secured. We will lift the tethered free float chambers to the center of the cabin and monitor that the tether does not allow for excessive impacts with cabin and items in the cabin. We will monitor for integrity loss of any chambers and will provide for immediate cleanup should integrity be breached.
What we expect to measure in 20 seconds.
For the set of hydroponics chambers that remain secured and those that are on a tethered free float during the parabolas we will observe integrity of flight apparatus, integrity of hydroponics chambers, integrity of substrate, integrity of study specimens. During and after flight we will observe any additional adverse effects on study specimens. After flight we will carefully review video recorded observations that can be slowed down to more carefully look for movement of study specimens, movement of substrates, signs of stress or loss of integrity of hydroponics chambers and flight apparatus.
Hydroponics chambers approximately 22cm 3 (based on current information regarding harvest size of Astroplants) will be designed and built with considerations for both flight and growth specifications. Design specifications include: liquid tight, low mass, sturdy, clear for light, accessibility to plant and harvest the food crops, reusable, inexpensive, etc. Intended material for build is most likely plexiglass. Additionally the chambers will contain the grow gel substrate plus the polyglycolic acid mesh and the specimens. Three apparatus will be designed and built that will each hold 2 hydroponics chambers with grow gel substrate and study specimens. This means the apparatus will be approximately 22cm x 45cm plus the extension for the recording camera. Only 2 of these apparatus will fly.