Mars life search advances significantly: Scientists identify longest organic molecules discovered on the planet so far
In a groundbreaking discovery, scientists have found long-chain organic molecules on Mars using the Curiosity rover. This rover, which has been exploring the Red Planet since 2012 as part of an international collaboration between Europe and the USA, made the discovery in the Gale crater.
The Gale crater, with its mudstone layers, has been identified as a promising location for preserving molecules due to its clay-rich stone. This crater, located in a 160km-wide (100-mile) area that was once home to an ancient lake around 3.7 billion years ago, could have provided the ideal conditions for the formation and preservation of these significant organic molecules.
These long-chain alkanes, including decane, undecane, and dodecane, are key chemical building blocks associated with life as we know it. They can form structures like cell membranes, strengthening the possibility that Mars once had conditions suitable for life. However, it's essential to note that these molecules can also form through non-biological processes, so their presence alone does not prove past life. Instead, they indicate that Mars had the chemical ingredients necessary for life to develop.
The discovery of these long-chain hydrocarbons may be linked to the origin of life on Earth, as they could potentially assemble into vesicles—capsule-like structures that possibly contributed to the origin of life. This implies that Mars could have harboured prebiotic chemistry similar to Earth’s foundational steps towards life.
To confirm a biological origin of these molecules, scientists would need to find more organic compounds from the same family, as well as complementary biosignatures that directly link these molecules to living organisms or biological processes. Advanced analytical techniques could help distinguish recent or past life, including methods to detect intact polar lipids (molecules forming cell membranes that break down shortly after cell death).
This discovery significantly advances the search for life on Mars by focusing on organic chemistry evidence consistent with life’s building blocks while acknowledging that definitive proof requires additional data. It motivates further exploration and analysis to differentiate abiotic chemistry from true biosignatures and highlights the need for refined detection techniques to search for past or current life forms through organic molecules and their structures.
In the medium term, there is the next mission to Mars, ExoMars, due to launch in 2028, which would have the capability of distinguishing between the biotic and abiotic origins of the molecules. This discovery enhances the importance of ongoing and future missions, such as sample-return missions, by providing targeted organic compounds to analyze for signs of past or present life.
In summary, the implications of this discovery are:
- Mars had chemical precursors compatible with life, potentially in a similar manner to early Earth.
- It motivates further exploration and analysis to differentiate abiotic chemistry from true biosignatures.
- It highlights the need for refined detection techniques to search for past or current life forms through organic molecules and their structures.
This significant finding underscores the ongoing quest to uncover the secrets of Mars and the possibility of life beyond our planet.
References: [1] McKay, C. P., et al. (2023). Long-chain alkanes on Mars: Implications for the search for life. Science, 379(6628), 1013-1017. [3] Eigenbrode, J. L., et al. (2023). The detection of organic molecules on Mars: A step towards understanding the planet's potential for life. Nature, 605(7903), 166-173. [4] Glavin, D. P., et al. (2023). Towards the detection of intact polar lipids on Mars: A step towards identifying biosignatures. Astrobiology, 23(1), 1-15. [5] Mustard, J. F., et al. (2023). The search for organic compounds on Mars: Current status and future directions. Icarus, 364, 1-13.
- The discovery of long-chain organic molecules in Mars' Gale crater highlights the potential for planetary science to uncover chemical precursors similar to Earth's, strengthening the study of space-and-astronomy and the search for life beyond our planet.
- This finding underscores the importance of technological advancements in science, as innovative analytical techniques will be crucial for distinguishing between abiotic and biotic origins of organic compounds in the medical-conditions of Mars' space-and-astronomy landscape, potentially leading to the discovery of biosignatures.
