No, Mars does not have oil, natural gas, or coal in the traditional, economically exploitable sense that these fossil fuels exist on Earth. Petroleum is a hydrocarbon deposit that forms over millions of years from the buried remains of massive amounts of ancient biological matter, such as marine plankton. While Mars is not devoid of carbon, it lacks the sustained, widespread biological history and the specific geological conditions required to produce large, liquid reservoirs of traditional fossil fuels. However, the Red Planet does possess carbon-based resources that are being eyed for future human missions.
The Requirements for Earth-Like Fossil Fuels
The formation of petroleum on Earth is a complex, multi-stage process that requires specific biological and geological prerequisites, which Mars appears to lack. The process begins with an immense accumulation of organic biomass, typically microscopic marine organisms like plankton and algae. This dead matter must sink to the seabed and be rapidly buried under layers of sediment in an environment largely devoid of oxygen to prevent decomposition.
Over millions of years, accumulating sediment creates immense pressure and increases the temperature of the buried organic matter. This deep burial subjects the material to a process called catagenesis, where heat and pressure chemically alter it, first into a waxy substance called kerogen. With continued heating, the kerogen “cracks” into the lighter, liquid and gaseous hydrocarbon chains that constitute oil and natural gas.
These hydrocarbon mixtures must then migrate from the source rock and become trapped in porous structures, sealed by impermeable rock to form an exploitable reservoir. Mars lacks the necessary long-term, widespread anoxic conditions and the sustained, massive biological productivity seen in Earth’s ancient oceans. Without the immense initial volume of preserved organic matter and the subsequent deep burial, the formation of large, liquid petroleum deposits is scientifically improbable.
The Carbon-Based Compounds Found on Mars
Although Mars does not have traditional fossil fuels, spacecraft confirm the presence of various carbon-based compounds. Scientists have detected an array of simple organic molecules in Martian rocks, which contain carbon, hydrogen, oxygen, nitrogen, and sulfur. The Curiosity and Perseverance rovers found these organics in ancient lakebeds, such as Gale and Jezero Craters, preserved in clay-rich mudstone deposits.
Specific discoveries include small compounds like thiophenes, benzene, and toluene, found in pulverized rock samples heated by the rovers’ instruments. Scientists also detected the longest organic molecules yet found on Mars, including the saturated hydrocarbons decane, undecane, and dodecane, which have chains of 10, 11, and 12 carbon atoms. These longer chains are thought to be fragments of fatty acids, which are fundamental components of cell membranes on Earth.
These organic molecules are not evidence of oil, but rather point to a complex geochemical past, potentially formed through non-biological water-rock interactions or delivered by meteors. Methane has also been detected in the Martian atmosphere, exhibiting seasonal variations, though its source remains a subject of ongoing research. Regardless of their origin, these carbon compounds exist in small, dispersed concentrations within the rock, not as large, fluid reservoirs that could be pumped out.
Resource Utilization for Future Exploration
The lack of traditional fossil fuels does not halt plans for human exploration, as future missions will rely on In-Situ Resource Utilization (ISRU). This strategy focuses on manufacturing necessary supplies directly from resources available on the Martian surface and in the atmosphere. The most abundant carbon resource is the atmosphere itself, which is over 95% carbon dioxide (\(\text{CO}_2\)).
Engineers plan to use atmospheric \(\text{CO}_2\) along with hydrogen derived from subsurface water ice to create propellant for the return journey. The Sabatier reaction is frequently cited for this, combining hydrogen and carbon dioxide over a catalyst to produce methane (\(\text{CH}_4\)) and water. Methane is a highly desirable rocket fuel, especially when paired with liquid oxygen, which can also be produced on Mars.
This method provides a massive advantage, as producing propellant on Mars significantly reduces the mass that must be launched from Earth. A small amount of imported hydrogen can be leveraged into tons of fuel. The carbon compounds can also be used as feedstock for manufacturing, creating plastics and construction materials for habitats. By focusing on the atmospheric and subsurface resources, future missions can achieve self-sufficiency without needing to drill for liquid hydrocarbons.