Living Things Pod

2016 STEM Academy Living Things Pod Overview
This pod was developed around the common interest of the study of near space effects on living things. This group chose to investigate how near space would physically affect living things, and to investigate whether or not the animal's behavior would differ after the experimentation. The chosen invertebrates were worms as well as cockroaches. The non-Newtonian substance, commonly known as "Oobleck", was also added to the pod in order for an additional investigation.

Worm Behavioral Testing
Prior to the flight, 24 night-crawlers were obtained and used for initial behavioral studies to understand worm preferences. The first experiment was to test whether the worms preferred wet surfaces or dry surfaces. A piece of dry, white butcher paper was placed onto a table. Then a paper towel was moistened and laid onto the paper, so that half of the available space was moist, and the other half was dry butcher paper. Then a container was placed over the experiment so that there was still an airflow; however, there was no bias during the experimentation. The setup was left alone for a total of 10 minutes, after which the bucket was removed and the data was collected. The first trial of this experiment resulted in five worms on the dry side, and five on the wet side. This experiment was then repeated in order to confirm the findings. After this procedure was repeated, there were six worms on the dry side, and four worms on the wet paper towel after the experiment.

According to the student's preliminary research, these findings seemed slightly strange and unexpected. However, there are some plausible explanations for why this is. To begin with, the wet side was almost drenched, and the water distributed so that the dry side was not completely dry everywhere. The worms did not gravitate towards the edges that remained completely dry, rather they were close to the dividing line between the wet and dry portions. Even though they were on the dry side, it may have had the right moisture amount for the worms. Additionally, there should have been the same material for both the dry and the wet side. There might have been a worm preference based on the surface's texture rather than the moisture concentration.

In addition to whether the worms preferred moisture, another test was conducted to test if the worms preferred being underneath materials or above materials. In order to test this, four worms were placed underneath a moist paper towel, while another four worms were placed on top of an additional wet paper towel. They were once again covered and left alone for 10 minutes. After this time period, there were six worms that were underneath the paper towel, while only two remained above the paper towel. This agreed with the student’s hypotheses. Worms live underground and so it seemed reasonable to assume that the worms would try to bury themselves if they were placed on top of materials.

Worms in Near Space
Once the baseline behaviors were obtained, and all the initial worm measurements were taken, then it was time to prep the worms for the near space launch. A total of five worms were selected for the mission. They were placed in dirt within a small Ziploc container. In order to allow for airflow, holes were drilled within the top of the container. This was then placed within the living things pod and secured with duct tape.

Once the pod was recovered, the container was opened and the worms were checked. All of the worms were alive and moving. They appeared to be healthy and squirming. One note is that the lowest temperature during the flight was close to 25 degrees Fahrenheit. This prohibited the worms from freezing, since on past launches many biological matter and other invertebrates have actually frozen. The surprising factor was that the worms survived the low pressure. There was concern that a pressure gradient would cause the worms to swell and kill the worm. However, the worms survived the trip to near space.

Cockroaches
Cockroaches are notorious for their longevity and ability to live after trauma as well as in harsh conditions. It is commonly hypothesized that they would survive a nuclear war due to their tenacity. They are able to live for weeks after their head has been chopped off. Therefore, cockroaches were chosen to study. Students wanted to know whether or not the cockroaches would be able to survive the effects of near space. There were mixed theories as to whether or not they would in fact live. The main hypothesis was that the cockroach would be able to withstand the cold since preliminary research had stated that many cockroaches are able to be frozen and then warmed back up without any life issues. Due to their hard shell, it was also hypothesized that the insect would be able to withstand the changes in pressure. Once the hypotheses and procedures were created, then basic behavioral studies began.

Initial Cockroach Behavioral Analysis
The students examined what types of food the cockroaches enjoyed as well as made observations about the cockroaches’ interactions. Once the baseline behaviors were noted, then the students measured all of the cockroaches, which were all approximately 1.5” long. Then two cockroaches were selected for flight. They had distinct markings so that they could easily be identified. One of the cockroaches had a red marking on its back, and was named “Rose”. The other lacked this marking and had an all-black back and was referred to as “Timmy”. They were placed into another Ziploc container that was filled with assorted dried fruit, since this seemed to be their favorite. Once again air holes were drilled into the container’s lid and then the container was secured into the pod via duct tape.

Cockroaches in Near Space
After the flight, the cockroaches seemed dead; however, it was soon noted that twitching began. As time progressed, the cockroaches seemed to “unfreeze” and there was further activity noted. This initially made sense according to the initial research since cockroaches are able to be frozen and thawed without significant changes in their behavior and anatomy. However, further examination of these insects revealed that they did not in fact survive the launch. The twitching was simply postmortem spasms and the cockroaches were unable to survive the flight.

Oobleck
The final area of investigation for this pod dealt with the substance commonly known as “Oobleck”. While this is not a living thing, many students were passionate about this non-Newtonian fluid and so almost every group was able to conduct their own tests.

Non-Newtonian Fluids
A non-Newtonian fluid is able to change its viscosity or flow under different circumstances. Sometimes the rate at which it flow depends on the applied stress and can also be dependent upon time. In Newtonian liquids, they have a constant flow or viscosity. The fluid’s flow will change depending on pressure or temperature. However, with non-Newtonian fluids, the amount of force applied can cause the liquid to behave differently. Oobleck is a great example of a non-Newtonian fluid. It is able to behave like a solid under certain conditions, and like a traditional Newtonian liquid in other circumstances.

How to Make Oobleck
Making Oobleck is simple. The only ingredients are cornstarch and water. Water is added to cornstarch until the mix will flow very slowly. Once they are mixed, experimentation can proceed. The students discovered that if you simply hole a chunk of Oobleck in your hands, then it becomes runny and will drain off of your hand. However, if you try to punch a bowl of Oobleck it behaves as a solid and will resist deformation. If the Oobleck is rolled, then it forms a sphere. However, the moment that you stop rolling, the Oobleck simply melts away and becomes runny.

Oobleck in Space
Once the baseline Oobleck consistency was obtained and experimented with, the Oobleck was divided into small containers and the tops were duct taped shut to ensure that Oobleck would not leak onto the interior of the pods. Then these containers were secured to the inside of the pod and ready to launch.

After the flight, the Oobleck was retrieved and the students noted that it was acting as a solid. However, this is most likely due to the fact that it was simply frozen. As the time progressed, the Oobleck began to melt and the consistency was eventually the same as the control sample that was never exposed to near space.