Exploring the Chemistry of Mars

“Mars is there, waiting to be reached.” - Ben Aldrin

Space has always been an area of interest for science lovers. It holds a gazillion of mind-boggling phenomena and entities. Amidst its magnificent wonders, a tiny speckle becomes the science of planets.

Earth is one special planet capable of sustaining life. Now, the question that surfaces is, “Is there a possibility to find any other abode that can support life?”. Researchers are working on this and the close solution that they derived is trying to take life to Mars. It is a potential alternative, since evidence for living organisms has already been gathered. With a complete analysis of its chemistry and improved technology, the reach for the “Red Planet” is not far.

The hunt for the chemical properties of the planets started with the launch of the Mariner 6 & 7 spacecrafts, which both orbited within a range of thousand miles of Mars. The Infrared (IR) Spectrometer, the prime component of each spacecraft, used spectroscopy techniques to scan the atmosphere and surface of Mars and transmitted IR spectral data back to Earth. An Infrared Spectrometer measures the absorption of IR by a sample and processes an IR spectrum which defines the chemicals present in the sample. The spectrometers carried were designed with a 10-inch reflector telescope that channelled IR light to a beam splitter that parted them into two different detectors. Through this, it was possible to determine the composition of the Martian atmosphere, water vapour concentration in its atmosphere, the first evidence for solid CO2 in the upper atmosphere, observation of solid water and water hydrates on its surface, and detection of goethite that proves to be the first evidence for the presence of water on Mars.

The prime necessities for life to exist are air and water. The Martian atmosphere is 100 times thinner than that of Earth’s and contains traces of Carbon Dioxide, Carbon Monoxide, Water vapour, Noble Gases, Oxygen and Hydrogen. The atmosphere in Mars comprises of 95.1% carbon dioxide, 2.59% nitrogen, 1.94% argon, 0.161% oxygen, and 0.058% carbon monoxide. Since the concentration of N2 and Ar does not vary with temperature and pressure, CO2 becomes the major decider of the surface pressure attributed to its seasonal variation. The atmospheric surface pressure on Mars is more than 2 orders of magnitude lower than it is on Earth (6.34 Mbar). As for a human being, as the pressure drops, more pressure is exerted on the joints, which swells the muscles tissues and tendons of our body. Also, the cavities in our body filled with air get affected by the change in pressure and may result in severe pain throughout the body, thus making it unsuitable for humans to live on Mars without a spacesuit. The natural air on Mars is highly toxic, as the concentration of CO2 and N2 is extremely high, which proves to be poisonous. It is verified that the minimum oxygen concentration in the air required for breathing is 19.5%. Mars is acutely short of oxygen. Transportation of oxygen from Earth is hugely resource consuming and expensive. A recent experiment, MOXIE, was built in an attempt to resolve this breathing inconsistency for humans on Mars. The Mars Oxygen In-Situ Resources Utilization (MOXIE) experiment has the aim of converting the available air on Mars to Oxygen. NASA’s Perseverance Rover conducted this experiment on Mars. MOXIE works by sucking the Carbon Dioxide from the Martian atmosphere and heating it to about 800 degrees Celsius, thereby reducing CO2 to O2 with CO as a by-product. Initially, five grams of Oxygen was produced that allowed humans to breathe for ten minutes on the Red Planet. Though this isn’t sufficient for fulfilling the dream of humans on Mars, it is a promising start towards the goal.

“On Earth, water means life” - Alberto Fairen, eminent astrobiologist.

Ages ago, Mars comprised a thicker atmosphere with water running on the planet’s surface without evaporation. Many pieces of evidence prove that the planet was once wet, lifting hopes of future life on Mars. Water quenches thirst and nurtures life. In addition to that, water is also used to shield us from radiation, and as Hydrogen fuel. There are traces and implications of ancient rivers and oceans on Mars. Nonetheless, at present, water on Mars is expected to be in its polar caps, unfortunately in frozen form. Researchers suggest that frozen water is not only available at higher altitudes but also beneath the surface of Mars. Melting all of this frozen water may result in flooding the total surface of the planet. Hydrated minerals with water in their chemical bonds also contribute to the water availability on Mars. From readily available clays to carbonates, sulphides and chlorides, hydrated minerals extend throughout Mars, bearing the ability to transform into water anytime. It is believed that these minerals were formed by the extinct water bodies and may have been buried underground, and now, resurfaced due to erosion. The images of Mars having dark, narrow lines on its slopes denote that once it occupied the course of water. In the origin of this universe, Mars and Earth were more like each other. Thus, it can be speculated that life may have started on Mars. If this is true, further inspection of the cause for the wipe-out of life on Mars might aid in predicting the future of Earth.

Now, to highlight the motive of this write-up, let’s try to answer the question, “How chemistry will help put humans on Mars?”. The answer is simple. The secret to putting humans on Mars comes from the combined effort of chemists and rocket scientists to ensure their safe travel. Chemistry plays a major role in creating a favourable niche for life on Mars. It bears solutions for plant growth, production of medicines and even for generating breathable air (MOXIE). The goal starts with the creation of a safe and economical flight from Earth to Mars. The demand for light and durable materials for spacecraft is now prevalent. The use of a breakthrough material, carbon nanotube, is currently encouraged over carbon fibre which was supposed to be the strongest and stiffest material. Carbon nanotubes, made up of strong bonds between nanosized carbons, top carbon fibres in weight and strength. They are 2000 times smaller and 20 times stronger than carbon fibres. Being lightweight, carbon nanotubes allow the spacecraft to escape the grasp of Earth’s gravity with ease. The only hindrance holding the “Man on Mars” project back, other than technology, is its cost. New methods are continually proceeded to enable a more economical model that allows hundreds of people to reach Mars simultaneously. For human survival on Mars, food and medicine can be produced through in-situ manufacturing which makes products from the available resources on Mars. The beneficial resources on Mars happen to be the Astronauts’ N2 rich urine and the CO2 in their breath. These resources can be harnessed to obtain favourable products, for instance, setting up a space factory involving a species of yeast named Yarrowia lipoytica that can convert feedstock into useful products like Omega3 fatty acids and polyester. The former can be used as a food supplement whereas the latter can be used to prepare any product that is required and can be made from polyester. This waste to wealth model will ensure a long run for humans on Mars.

The article concludes on a positive note on ensuring the hope for Man to reach Mars one day. Despite the bounty mars can offer, humans must bear in mind that Earth is our first home sheltering our growth and greed for 2 million years. The least that can be done to pay homage to Earth is by curbing contamination and judicious use of resources. With the growing expanse of our technology and discoveries, we must learn to be more cautious and benevolent for the sake of peaceful co-existence in this universe.

Thank You!

-Sahana G