UtSTA 2024: Out-Of-This-World Science Teaching

Carbonaceous chondrites (carbon-rich meteorites) represent some of the oldest and most primitive pieces of material formed in the Solar System; indeed, they could even be older than the Sun itself. These carbon-rich meteorites may have delivered an important concentration of organic compounds and water to the primitive Earth. Multiple organic classes, including those required for life (e.g. amino acids, carboxylic acids, nucleobases, and polyols) have been identified from carbonaceous chondrites, providing valuable insights into the chemical inventory of the early Solar System, the primordial synthesis of organic matter, and the question of how life appeared on Earth.
Amino acids are the basic building blocks of all protein-based life on Earth, making them some of the most fascinating organic compounds found in meteorites. In earthly biology, proteins are mostly made up of the L-form of amino acids, a feature crucial to life as we understand it. Some meteoritic amino acids also show a preference for the L-form, which raises intriguing questions about a possible connection between meteorites and this biological preference. Additionally, the stable isotopes (D, 13C, 15N) found in meteoritic organic compounds can tell us about how they formed and their history. By comparing the distribution, chirality, and isotopic composition of these compounds in different types of carbonaceous chondrites, we can learn more about the composition and conditions of the early solar system, the bodies where meteorites originated, and possibly how these compounds were made and survived the solar system's formation.
I will present results from our extensive investigation on the abundance and molecular distribution of amino acids, and other biologically relevant molecules extracted from meteorites. We will discuss their potential prebiotic origins and relevance to the emergence of life on Earth. We will also review the importance of sample return missions and our future findings after the analysis of asteroid samples brought to the Earth by JAXA’s Hayabusa2 and NASA’s OSIRIS REx.