What Lies Beneath? Uncovering the Water of Mars

Scientists have discovered that water exists on Mars, but it is hidden under the surface.

For hundreds of years, humanity has sought a suitable planet to inhabit. Three things are required for a planet to be suitable: an atmosphere, a temperature not too hot, and a temperature not too cold. The planets that fit these criteria are known as Gol‌dilocks planets. In the past, scientists have considered the possibility of inhabiting Mars, but quickly moved on due to the lack of an atmosphere. But what if I told you that there is proof that Mars has water under its surface? No, not the ice caps—in the mid-crust section of the planet, there are igneous rocks saturated with water (1, 2). 

InSight (Interior Exploration using Seismic Investigations, Geodes, and Heat Transport) was a stationary lander sent to Mars on May 5th, 2018 (3). It collected data about the depth of the crust, the temperature of the mantle, and the composition of the atmosphere and core. Most importantly, it collected data about marsquakes, the term for seismic activity on Mars. This allowed scientists to study the composition of the crust by using the speed at which the quakes traveled (1, 2, 3).

https://science.nasa.gov/resource/artists-concept-of-insight-lander-on-mars-annotated

Many different methods were applied to determine if water was in the mid-crust. Among these methods were the rock physics model, the Gassmann-Biot fluid substitution theory, and the Bayesian inversion (2). In short, a rock physics model links the physical properties of rocks, such as porosity, composition, and fluid content, to their elastic properties (4). By analyzing seismic activity, scientists can figure out the properties of the rock, which are vital to assessing the presence or absence of water (2). Scientists also used the Gassmann-Biot fluid substitution theory to determine the liquid composition. Gassmann-Biot fluid substitution can be broken up into three simple parts: Understanding rocks’ framework, Gassmann’s equations, and Biot Theory. The elasticity of a rock is based on the frame and the liquid in the pores of the rock. Gassmann’s equations let us relate the saturated rock’s bulk modulus (incompressibility) to that of the unsaturated rock and the liquid. Biot theory works to include dynamic processes such as wave propagation in the analysis (2, 5). Bayesian inversion, which essentially uses data to refine the initial model, was used here to improve the model of the mid-crust (2, 6). 

So what? Why does it matter that we found water under Mars’ surface? There are three major reasons why this groundbreaking discovery is significant. First is the obvious: water is the essence of life. Since life stems from water, there is potential for life deep underground. Secondly, by analyzing the water, we can discover how Mars’ surface ended up as an inhospitable wasteland, while Earth’s surface ended up as a flourishing green landscape. Lastly, the water could serve as an extremely valuable resource for future missions to Mars. With this discovery, astronauts could potentially drink or irrigate crops with water while inhabiting Mars. 

The discovery of water beneath Mars’ surface marks a significant milestone in the exploration of celestial bodies in our solar system. This finding deepens our understanding of Mars’ geological history and opens doors to further exploration, inhabitation, and maybe even life on Mars. As we continue to study these hidden reservoirs, we take one step closer to unraveling the mysteries of our solar system and potentially figure out if Martians prefer their water still or sparkling.

  1. Strickland, A. (2024, August 12). Underground reservoir on Mars could fill oceans on the planet’s surface, study finds. Retrieved September 29, 2024, from CNN website: https://www.cnn.com/2024/08/12/science/mars-crust-water-reservoir-insight/index.html 
  2. Wright, V., Matthias Morzfeld, & Manga, M. (2024). Liquid water in the Martian mid-crust. Proceedings of the National Academy of Sciences, 121(35). https://doi.org/10.1073/pnas.2409983121
  3. Artist’s Concept of InSight Lander on Mars (Annotated) – NASA Science. (2015, December 22). Retrieved September 29, 2024, from Nasa.gov website: https://science.nasa.gov/resource/artists-concept-of-insight-lander-on-mars-annotated/ 
  4. Reine, C. (n.d.). Rock-Physics Models -A Tutorial. Retrieved from https://geoconvention.com/wp-content/uploads/abstracts/2020/57755-rock-physics-models-a-tutorial.pdf
  5. Al-Khateb, N. (n.d.). A look into Gassmann’s Equation Theory and/or Method The Influence of Pore Fluids on Seismic Properties. Retrieved from https://geoconvention.com/wp-content/uploads/abstracts/2013/316_GC2013_A_look_into_Gassmanns_Equation.pdf 
  6. Kolehmainen, V. (2007). Bayesian Inversion; Examples and Computational Aspects. Retrieved from https://www.math.colostate.edu/~mueller/graduate_workshop/lectures/kolehmainen/kolehmainen.pdf