Two Japanese research teams have analyzed rock samples from the asteroid Ryugu, one of the oldest and most primitive objects in the solar system, together with international experts.
After a journey of six years and 5.2 billion kilometers, the Hayabusa2 probe dropped on December 6, 2020 over Australia a container with a small amount of dust and gas from Ryugu.
Hayabusa2, launched in 2014, made contact with the surface of Ryugu twice in 2019 to collect the samples in a complex and historic operation, and after a journey of six years and 5.2 billion kilometers, dropped them in a container over Australia on December 6, 2020.
The team that has investigated the samples of the remote asteroid Ryugu found carbonated water with salts and organic matter inside, a finding that, they say, would support the hypothesis that life came to our planet from space.
During the analyses, “liquid water was discovered inside a sample crystal. This water was carbonated, contained salts and organic matter, which was once present in the main body of Ryugu,” according to the report published today by the Japan Aerospace Exploration Agency (JAXA) and “Science” magazine.
The report is published on the occasion of the first anniversary of the start of the study of the samples collected by the Japanese space probe Hayabusa2 in a pioneering mission, and their results would support the hypothesis that water and organic matter reached Earth through asteroids and other bodies, depending on the team.
There are several theories about the appearance of life on Earth. Some point out that it arose little by little from inorganic molecules that gave way to organic compounds such as amino acids, while others hypothesize that organic compounds could have arrived in meteorites.
The researchers, led by Professor Nakamura Tomoki of Tohoku University, have already revealed the finding of amino acids in the Ryugu samples, considered one of the pillars of life.
Carbonated water and organic matter
The drop of water in particular was found inside an iron sulfide crystal that also contained carbon dioxide (CO2).
Crystals similar in shape to coral reefs were also seen on the surface of the samples, which are believed to have grown in liquid water within Ryugu’s original body, which would once have had abundant water.
The researchers, divided into six teams and two conservation institutes around the world, also carried out analyzes of the hardness, thermal conductivity and magnetism of the 17 particles brought from Ryugu, and through the results of which they simulated their formation 4.6 billion years.
According to his estimates, the original body to which it belonged was about 100 kilometers in diameter, was born in the dark in a primordial nebula far from the Sun and no longer exists, and was mainly composed of rock and ice.
His original body was born with a temperature of about -200 degrees Celsius, although high-temperature particles have been found that are believed to have traveled from near the Sun to the outer system.
Ryugu’s main body would have been destroyed by a collision and the researchers believe that it could have belonged to the family of asteroids Polarna or Eulalia, and that all would have arisen from the destruction of the original body of Ryugu. (YO)