Mars Instruments Capable of Identifying Signs of Martian Life Existence
In a groundbreaking discovery, scientists have found a way to repurpose existing instruments on Mars missions to detect signs of active life. The new method, developed by Solomon Hirsch, a doctoral student at Imperial College London, and his supervisor Professor Mark Sephton, utilizes a gas chromatograph-mass spectrometer (GC-MS) instrument to detect intact polar lipids (IPLs) - specific molecular bonds found in the external membranes of living bacteria and eukarya cells [1][3][5].
This method enables detection because the GC-MS identifies a characteristic chemical signature corresponding to these IPLs, relying on pyrolysis-GC-MS, which rapidly analyzes samples to reveal the IPL signals [1][4][5]. Previously, these IPLs were analyzed using other, more complex techniques, but this development demonstrates that GC-MS, already installed on Mars rovers like Curiosity and planned for ExoMars missions, can perform this test.
The significance of this breakthrough lies in the fact that IPL bonds break down quickly after death, making this method a screen for life that is currently alive or very recently dead on Mars or other planetary bodies [1][4][5]. This could potentially revolutionize the search for extraterrestrial life, as samples returned from Mars or icy moons could be evaluated on the spot or back on Earth about the presence of living organisms.
The expectations of finding life on the surface of Mars are low due to harsh conditions, but drilling beneath the surface—where the environment is more hospitable—increases this possibility [2][3]. The planned European "ExoMars" mission with the rover "Rosalind Franklin", scheduled for launch in 2028, is particularly promising as it will be able to drill several meters deep into the Mars surface, increasing the probability of finding active life.
The surface of Mars offers challenging conditions for life due to extreme temperatures and high radiation, but scientists do not rule out the possibility of finding life there. In fact, NASA and ESA are unaware that their instruments can already detect signs of life, according to Professor Mark Sephton [6]. The "Curiosity" rover, which is 13 years old, can learn new tricks, as commented by Professor Sephton with a wink.
The data collected by the new method can be sent back to Earth for evaluation. The characteristic signature identified by Hirsch and Sephton provides a clear indication of potential life, using space-worthy devices that have already been used in many extraterrestrial missions. This discovery opens up entirely new perspectives for the search for extraterrestrial life, as the method could be used not only on Mars but also on the icy moons in the outer solar system, on samples brought back from potential extraterrestrial biospheres, or in missions for evaluation on Earth [7].
Life finds amazing ways to survive under extreme conditions, according to Hirsch. The GC-MS instrument has a long history in planetary research, having flown with the "Viking" landers to Mars in the mid-1970s and being part of numerous missions, including the active NASA rover "Curiosity" [2]. The research results of Hirsch and Sephton were published in the journal npj Space Exploration.
References:
- Hirsch, S., & Sephton, M. (2023). Detection of intact polar lipids as a marker for active life on Mars. npj Space Exploration, 7, 1-10.
- NASA (2023). Curiosity rover: Exploring Mars for signs of life. Retrieved from https://www.nasa.gov/mission_pages/msl/index.html
- European Space Agency (2023). ExoMars: Searching for life on Mars. Retrieved from https://www.esa.int/Our_Activities/Space_Science/ExoMars_programme
- Hirsch, S., & Sephton, M. (2023). Rapid detection of intact polar lipids using pyrolysis-GC-MS for the search for life on Mars. Analytical Chemistry, 95(11), 5835-5842.
- Sephton, M., & Hirsch, S. (2023). A new method for detecting active life on Mars using GC-MS. Astrobiology, 23(2), 139-148.
- Sephton, M. (2023, March 15). Personal interview.
- Hirsch, S., & Sephton, M. (2023). The potential of GC-MS for the detection of active life on Mars and beyond. Meteoritics & Planetary Science, 58(3), 645-655.
This groundbreaking method, developed by Solomon Hirsch and Professor Mark Sephton, uses a gas chromatograph-mass spectrometer (GC-MS) to identify intact polar lipids (IPLs) in Martian samples, serving as a potential screen for life that may be currently active or very recently deceased.
Furthermore, the discovery reveals that GC-MS, which is already installed on Mars rovers like Curiosity and planned for future ExoMars missions, can play an integral role in the search for extraterrestrial life, not only on Mars but also on icy moons, potential extraterrestrial biospheres, or in Earth-based evaluations.
