Scientists have begun to look for extraterrestrial life in the Solar System, but such life may be microscopically or profoundly different from Earth’s life, and biosignatures can be based on life with a different evolutionary history based on the detection of particular molecules. May not apply.
A new study by a joint Japan / US-based team led by researchers from the Earth-Life Science Institute (ELSI) at the Tokyo Institute of Technology reports on machine learning techniques using mass spectrometry to classify them Assesses complex organic mixtures. As biological or biological.
In season 1 of episode “Star Trek” (“Operation: Annihilate!”), Episode 29, which aired in 1966, the human-Vulcan hybrid character Spock says, “It’s not life as we know it or understand it.
Then Also it is clearly alive; it exists. ” This now 55-year-old episode makes a point: how can we find out life if we don’t know fundamentally what life is, and if that life is actually different from life as we know it?
The question of whether or not we are alone as living beings in the universe has attracted humanity for centuries, and mankind has been searching for supernatural life in the solar system since NASA’s Viking 2 mission Mars in 1976. The pursuit of life involves listening to radio signals.
From advanced civilizations in deep space, looking for subtle differences in the atmospheric composition of planets around other stars, and trying to measure this directly in soil and ice samples collected using spacecraft in our own solar system .
This last category allows them to bear their most advanced chemical analytical tools directly on supernatural samples, and perhaps even brings some samples back to Earth, where they can be studied.
Missions like NASA’s Perseverance Rover will seek life on Mars this year; NASA’s Europa Clipper, launched in 2024, will try to sample ice extracted from Jupiter’s moon Europa, and its Dragonfly mission will attempt to land an “octacopter” on Saturn’s moon Titan starting in 2027. All these missions will try to answer the question whether we are alone.
Mass spectrometry (MS) is a major technique on which scientists will rely for extraterrestrial life in spacecraft-based discoveries. The technique can simultaneously measure multiple compounds present in samples, and thus provides a type of “fingerprint” of their composition. Nevertheless, those fingerprints can be difficult to interpret.
As scientists can tell, all life on Earth is based on the same highly coordinated molecular principles, which convince scientists that all life on Earth is derived from a common ancient terrestrial ancestor.
However, in simulations of primitive processes, which scientists believe may have contributed to the origin of life on Earth, many similar but slightly different versions of terrestrial life use of particular molecules are often explored. In addition, naturally occurring chemical processes are also capable of producing many building blocks of biological molecules.
Since we still have no known specimen of alien life, this leaves scientists with an ideological paradox: whether Earth’s life made some arbitrary choices early in development, and thus, the creation of life otherwise Could it have been done, or should we expect everywhere to be constrained exactly the way it is on earth?
How can we know whether the detection of a particular molecule type is an indication of whether it was produced by supernatural life?
This has long puzzled scientists that biases toward similar life forms of Earth’s life may thwart their detection methods. Viking 2, in fact, returned strange results from Mars in 1976. Some tests conducted by this indicated signs considered positive for life, but MS measurements provided no evidence for life as we know it.
Recent MS data from NASA’s Mars Curiosity Rover suggest that there are organic compounds on Mars, but they still do not provide evidence for life.
A related problem has led scientists to try to find early evidence for life on Earth: can we tell if the signs found in ancient terrestrial samples are from the original living organisms preserved in those samples, or from contamination by those organisms Received who are currently occupying the planet?
Scientists at the Earth-Life Science Institute at the Tokyo Institute of Technology in Japan and the National High Magnetic Field Laboratory (The National MagLab) in the US solved this problem using a combined experimental and machine learning computational approach.
Using ultra-high-resolution MS (a technique known as Fourier-transform ion cyclotron resonance mass spectrometry (or FT-ICR MS)), they measured the mass spectra of a variety of complex organic mixtures, including biological samples. Contains derivations from.