Amputated flatworms, ant farms, and talking zucchini sounds fanatical, right? Such unrealistic creatures were created and rigorously tested at the International Space Station (ISS), under highly controlled experiments to see the viability of such creations in unusual conditions present in the lower earth orbit.
International Space Station is a satellite designed in a way that is habitable by humans even in un-habitable situations. One might see it as a white spot on the sky that flashes across our vision without changing direction. Under the supervision and collaboration of five main agencies named NASA, JAXA (Japan aerospace exploration agency), Roscosmos (Russia), ESA (European space agency), and CSA (Canadian space agency), the International space station is a hub of genius brains that are open to unique experimentations, innovations, and ideas.
A question that pops up in mind is: What is the real motivation behind such experimentation? The main aim is to observe the influence of microgravity on physiological processes to further expand our knowledge about biology.
International Space Station conducts experiments related to diverse fields such as space sciences, biological sciences, physical sciences, and many more. The article below primarily sheds light on the eccentric yet amazing biological experiments conducted at ISS.
Researchers at Allen Discovery Centre at Tufts University sent planarian flatworms to ISS to observe the effect of microgravity and micro geomagnetic field on the growth and regeneration of these worms. The purpose was to determine if earth induced changes persist in these worms once they would be back to earth from space. Cleaved and fragmented flatworms were sent into space in half-filled water tubes. After a period of 20 months, these worms were sent back to earth. The most surprising aspect that was found: one of the flatworms with cleaved head regenerated a rare double head. This was rather an astounding occurrence, never found before. Furthermore, when researchers abscised the heads of the space sent worms on earth, the middle headless region regenerated into a double-headed worm. Another significant change observed by scientists at Tufts was that the non-amputated flatworms sent to space experienced spontaneous fission (splitting) unlike the worms sent back to earth.
In response to these variances, scientist started drawing possible explanations to justify this behavior. Temperature change and light intensity were thought to be responsible for observed variations. Further experiments were conducted to determine the effect of both of these factors on different species of flatworms.
Ant-stronauts farm or ant farm was an experiment conducted under the supervision of Ecologist, Deborah Gordan back in 2014 with the motive of observing the response of ants while solving a collective search problem. It was pivotal to get an insight into how ant colonies adapt as a group in extreme conditions (microgravity) to figure out various algorithms they employ to do so. The advantage of this experiment was two folds: Questing for new algorithms and using those algorithms for application in robotics.
The experimental design included the use of pavement ants or Tetramorium caespitum. Eight ant groups each with 100 individuals were sent to ISS. A control experiment using a similar number and types of ants was set up back at earth to compare the results. Cameras were installed and software was used to monitor ant movements and their interactions, hence determining the influence of microgravity on their motion. The group density of ants in an area is needed in many instances such as food search. The density of ants is inversely related to the area of ground they cover. Higher density in a given area causes them to move in a circular motion in the same area. Lower ant density at a respective area favors their movement in a roughly straight path hence covering more land area. In an interview with a BBC reporter, Gordon said, “The idea is to ask the ants to search a small space- and then provide more space and see what will happen when the same number of ants have to use a larger space.”
In a TED talk, Gordon commented “The idea here is that the ants are working so hard to hang on to the wall or the floor or whatever you call it, that they are less likely to interact and so the relationship of how crowded they are and how often they meet would change.”
Funded by the NCATS (National Centre for Advancing Translational Sciences) program and NIBIB (National Institute of Biomedical Imaging and Bioengineering), the tissue and organ on chip research experiment laid its roots in ISS to get in-depth knowledge of human physiology and diseases. This will enable scientists to get clarity on the tissue functions and potential treatments of human diseases in unconventional conditions. The invention of such chips in outer space encompassed many scientists and researchers like those associated with genomics, pharmacology, pathology, disease biology, and many more.
This experiment comprised of two phases. In the first phase, researches developed and tested tissue chips at ISS science labs, under the influence of microgravity. The second phase shed light on the potential use of these tissue chips before clinical trials took place. This aimed to ensure efficient functionality and a better understanding of the work.
The first NIH-supported tissue chip was launched into space on December 2018 as reported by NCATS. In May 2019, four more NCATS-funded tissue chips reached ISS. These four chips were analogous to lung and bone marrow, bone and cartilage, kidney and blood-brain barrier that protects our brain. Added to this, a third chip was launched in March 2020 that focused on cardiac and intestinal tissues. These experiments are set on the road of progress to open up new opportunities and endless world of possibilities to produce something beneficial to humanity even in unique conditions such as those found in lower earth orbit.
Ever heard the term Talking Zucchini? Don Pettit coined this term, in his blog “Diary of a Space Zucchini”, to narrate the story of Talking Zucchini where he personifies zucchini. This story is the life experience of a four-leafed zucchini’s sprout grown in space. Just like any other biological experiment conducted in outer space, the aim of performing this experiment was to learn the impact of microgravity on the growth of a plant.
The experimental design includes the aeroponic method of growing plants where the plant is enclosed in an air-filled bag with a small amount of water placed primarily at the corners of the bag. Water is pulled up via capillary forces in weightlessness to ensure the supply of nutrients needed for its growth. Pettit, as the plant itself, mentioned in the blog, “These 16 short periods of day and night every 24 hours are making me jet-lagged. My photosynthesis activity just gets going and then abruptly shuts down. Repeating this cycle is putting me into a dither. My leaves do not sing as loud.“
Zucchini was not the only plant that was tested; sunflower and broccoli also became part of this experimentation. Sunflower stood upright, whereas broccoli didn’t grow so lively. It’s week and small sprouts are revealing its story.
This is not the end though. The experiments described above are just a few of many that are constantly being performed in outer space that includes space squids and space mice. In near future, there may be an in-depth study of one of these experiments that could trigger the development of essential tool for human well being. Numerous other experiments are yet to be seen, more unusual and more complex areas of studies are yet to be revealed. The more we explore, the more we enlighten our minds with untapped theories and un-explored scientific knowledge.
As Brian Cox said:
–“There are billions of places out there that we know nothing about. The fact that we know nothing about them excites me, and I want to go and find about them- And that’s what science is”.
Also Read: Space Missions; Insights from the past
Maira Masood is a BS Biosciences student at NUST, Pakistan. She aspires to be a geneticist and wants to play an active part in spreading scientific awareness through writings.