Organic compounds are the building blocks of all known terrestrial life and consist of a wide range of chemicals made up of carbon combined with hydrogen, oxygen, nitrogen, sulfur, and other chemical elements. However, organic compounds are not an exclusive product of biological activity but can also be formed by chemical reactions that do not involve life, which supports the hypothesis that there are chemical reactions on asteroids that can make some of the ingredients of life. .
A recent analysis of a sample taken from the Ryugu asteroid and brought to Earth by the Japanese space probe Hayabusa-2 reveals that the material is rich in organic compounds.
The discovery reinforces the idea that organic matter from space contributed to the inventory of chemical components necessary for life on Earth.
The analysis was carried out by a team including Hiroshi Naraoka of Kyushu University in Fukuoka, Japan, and Daniel Glavin of NASA’s Goddard Space Flight Center in the United States.
There is great interest in discovering the substances and chemical reactions that could give rise to life on Earth and perhaps on other worlds, and among the prebiotic organic compounds found in the sample are amino acids of various types. Certain amino acids are widely used by terrestrial life as building blocks for proteins. Proteins are essential to life, as they are used to make enzymes that regulate or speed up chemical reactions and to make structures ranging from microscopic to large in size, such as hair and muscles. The sample also contains many types of organic compounds that form in the presence of liquid water, such as aliphatic amines, carboxylic acids, polycyclic aromatic hydrocarbons, and nitrogen-containing heterocyclic compounds.
Hiroshi Naraoka working on Ryugu sample handling in a clean room at Kyushu University. (Photo: JAXA)
The presence of prebiotic molecules on the surface of the asteroid despite the very hostile environment due mainly to the ultraviolet irradiation of the Sun and the incidence of cosmic rays, suggests that the grains that rested just above the samples, and presumably those on a good part of the asteroid’s surface are capable of protecting organic substances, as Naraoka argues. These substances can be transported throughout the solar system, potentially dispersing as interplanetary dust particles after being ejected from the asteroid’s top layer by impacts or other causes.
Hayabusa-2 collected the analyzed sample and others on February 22, 2019. The capsule with the samples reached the Earth’s surface on December 6, 2020.
The Hayabusa-2 mission is from JAXA (Japan Aerospace Exploration Agency) and the DLR (German Space Center), CNES (French National Center for Space Studies), NASA (US space agency) have also collaborated on it. ) and the ASA (Australian Space Agency). (Fountain: NCYT de Amazings)