A long, long time ago, people on Earth began to think about questions related to life. How did life on Earth come into existence? In this vast universe, is Earth the only place where life has emerged by various chance ......
Not long ago, another possibility was found that might answer these questions. 2020 saw the return to Earth of the Japanese space probe Hayabusa 2, which found more than 20 amino acids after analyzing the samples it took from the asteroid Ryugu.
▲ Image from: JAXA
In December 2014, the Hayabusa2 asteroid probe lifted off on a rocket under the Japan Aerospace Exploration Agency's (JAXA) asteroid detection program.
The goal of this probe is to explore the origin and evolution of the solar system by investigating S-type asteroids (silica-dominated) and C-type asteroids (carbon-containing asteroids). In June 2018, Hayabusa 2 arrived at the C-type asteroid called Ryugu (Dragon Palace).
▲ Image from: JAXA
Before returning to Earth, Hayabusa 2 collected two samples from different locations on the C-type asteroid Ryugu, one from the surface of the planet Ryugu and the other from subsurface material in a crater formed after an artificial collision.
Amino acids, as organic compounds, are the building blocks of proteins, and in the current mainstream theory of the origin of life, proteins are the basis of life, and therefore amino acids can be considered the "source of life".
▲ Image from: JAXA
In the 1950s, Stanley Miller and Harold Urey conducted an experiment in which gases present in the primitive atmosphere, such as methane, ammonia, and hydrogen, were sealed in a large flask with a flask containing water attached to the other end. When water was heated, the vapors were introduced into the flask containing the chemicals, simulating a miniature primordial atmosphere.
▲ Image from: Ars Technica
Meanwhile, in this environment, electrode discharges were used to simulate lightning, and the cooled vapors condensed into a liquid that was collected like water sinks into the ocean. In the final collected samples, amino acids, many fatty acids, and rich organic matter such as uric acid were found.
The results of this experiment were thought at the time to indicate that life was born on the ancient earth like a 'primordial soup' after complex activities such as meteorite drops and volcanic eruptions.
▲ Image from: learn-biology
In fact, amino acids have been found on meteorites that have fallen to Earth before, but because meteorites may be affected by the Earth's environment during their fall, it cannot be determined whether conditions exist for life to be born in extraterrestrial space.
So, this discovery of amino acids on an exoplanet has led to bold speculation that on early Earth, it may have been the impact of matter from space that made the birth of life possible. If it's not just the Earth that has amino acids, then on other planets, there is the possibility of life being born as well.
▲ Image from: Unsplash
However, for now this is only a possibility, and while amino acids may lead to the birth of life under a variety of conditions, the process in between is complex and difficult to understand, and any mistake in between could cut off the path to life. But at least people now know that there is the possibility of other life being born in the infinite universe beyond Earth.