Enceladus, a moon of Saturn, one of the many places where life could possibly exist in our solar system. Discovered in 1789 by astronomer William Herschel, with a small diameter of around 504 kilometers, the moon stands out with its bright and icy surface. My team and I have chosen to study Enceladus and design a vehicle for it to travel safely while avoiding icy temperatures, around – 201 degrees Celsius, high power efficiency, geysers of water vapor, high brightness induced low visibility, dangerous radiation levels, and the possibility of escaping from Enceladus’s gravity pull (0.113m/s2).
We chose Enceladus because it has one of the crucial aspects of supporting life, water. Underneath just 2 kilometers of an icy shell lies a massive ocean kept liquid via the heat generated from tidal forces in its orbit. The tidal force causes friction with the moon’s core, keeping the ocean in a liquid state.
Water is important to life for two general reasons. First, as living beings we need water to live, our bodies are made up of 70% water. We used to drink, shower, and so much more. Secondly, large water bodies serve as solvent for molecules to interact and react. This is crucial for biological processes as in liquid water, molecules move freely enabling more complex chemistry. The existence of water is a sign for the possibility of life on Enceladus.
As we land down on Enceladus as a scout our general objectives would be to study the ocean, the thermal process, as well as searching for life. Since we are considering Enceladus as a new home, understanding the geological workings of it would be key to optimizing our resources. Currently, instruments such as Oxford’s Enceladus Thermal Mapper are being used to learn more about the moon. Oxford’s ETM uses a multi-band radiometric sensor with 384 cross-track scanning pixels that measure thermal emissions across different wavelengths. Operating within the orbit, it captures high resolution thermal maps of the moon’s surface displaying results that were not originally predicted.
Luckily, the surface of the moon is only 2 kilometers deep, making it easy to access the vast ocean underneath. Collecting samples of the ocean would be the ideal way for studying the moon. Even though Enceladus may be a potential new home, there are multiple challenges that we must face. The first most obvious obstacle would be the extreme temperatures of the moon. With an average temperature of -201 degrees Celsius ( -329.8 degrees Fahrenheit), the surface of Enceladus is coated in ice. There is, however, a dramatic warm spot centered on the South pole potentially suggesting a internal heat leak to the surface. Areas known as the “tiger stripe” fractures also contrast the normal temperature at around -177.7 degrees Celsius (-279 degrees Fahrenheit). The Tiger Stripes on Enceladus are four parallel fractures that emit plumes of water vapor and other icy particles into space.
Next, another challenge would be the low gravity on the moon, at around 0.113m/s2. The Cassini spacecraft carried out these gravity measurements by doing three close flybys at low altitudes and detecting changes in its trajectory. Low gravity would prove an obstacle as it weakens muscles, bone density, coordination, and causes bodily fluids to rush to our brain affecting vision and other functions. Another obstacle is the amount of radiation present on the moon. Primarily due to intense magnetic fields from Saturn, particles from the solar wind and other cosmic sources are trapped and accelerated. As Enceladus orbits around Saturn and its magnetic field, the moon is constantly bombarded by these particles. These high concentrations of radiation will damage our cells, break down chemical bonds within our bodies, and cause errors in our cell repairs. Luckily, Enceladus’s internal ocean remains shielded from this radiation under its icy crust, which helps preserve potential biosignatures in subsurface layers.
The vehicle that my team and I are designing must include tools that can combat such obstacles. Firstly, to combat the low temperatures we would design a thermal protection system that can maintain functionality in those low temperatures. This would protect the astronauts as well as the electronics from getting damaged by the cold. Next, to adapt to the low gravity, we would need grippy tires that would keep us from floating and still navigate the icy terrain. For gathering samples, we could borrow the Europa Clipper’s design that sends an ice-melting probe down beneath the surface.
Next, to combat the radiation, the outer layer of the vehicle should be built with radiation-hardened materials that can shield the vehicle’s systems. This could involve lead or other materials that protect sensitive electronics. Lastly, since Enceladus is so far away from the sun, solar power is not an available option. Instead, we would alternative energy sources, perhaps the internal geothermal power could help power the vehicle.
AI was used while writing the blog post – full transcript
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