New research yielded surprising results on samples of the asteroid Bennu that arrived on Earth in 2023. What does it mean that they have discovered that it has “bricks of life”?
The study, shared by scientists from Penn State University, in the United States, in the journal Proceedings of the National Academy of Sciencesrevealed that the samples contain amino acids or molecules that form proteins essential for life.
According to research, these molecules, also called “bricks of life,” They could have originated at the dawn of the early solar system. He points out that some Bennu amino acids could have been formed in a different way than previously thought, under harsh conditions in a radioactive and icy environment.
«Our results completely change the narrative about how we believed amino acids were formed in asteroids,» he defends. Allison Baczynskia geosciences researcher at Penn State and co-lead author of the study.
«It now appears that there are many conditions in which these basic components of life can form, not only when there is warm liquid water. Our analysis has shown that there is much more diversity in the routes and conditions of formation,» the scientist emphasizes.
120 grams of samples
Bennu has long intrigued researchers with its near-Earth orbit and carbon-rich composition. Scientists postulated that the asteroid contained traces of water and organic molecules and theorized that similar asteroids could have brought these materials to an early Earth.
In 2020, NASA’s OSIRIS-REx spacecraft collected samples from Bennu and in September 2023, as the spacecraft flew over Earth, it dropped a capsule with the samples that landed in the Utah desert, where they were recovered for study.
In total, there were some 120 grams of materialapproximately the weight of a bar of soap and twice the amount required by the mission. The valuable samples were distributed and loaned to researchers around the world for analysis, including those at Penn State.
To analyze the precious and scarce space dust – no more than a teaspoon – the team used instruments capable of measuring isotopes (slight variations in the mass of atoms), especially glycine, the simplest amino acid (a small two-carbon molecule that serves as one of the basic building blocks of life).
Amino acids are chained together to form proteins, which perform almost all biological functions, but glycine can form under a wide range of chemical conditions and is often considered a key indicator of early prebiotic chemistry.
That it is present in asteroids or comets indicates that some of the fundamental ingredients of life could have formed in space and been transported to the early Earth.
Chemically distinct regions
The new results suggest that Bennu’s glycine might not have formed in warm water, but in frozen ice exposed to radiation in the outer reaches of the early solar system.
For decades, scientists have examined carbon-rich meteorites, such as the famous Murchison meteorite that fell in Australia in 1969.
«What is a real surprise is that the amino acids in Bennu show a very different isotopic pattern than in Murchison, suggesting that these bodies probably originated in chemically different regions of the Solar System,» says co-lead author, Ophélie McIntosh.
Looking ahead, the results raise new mysteries such as that amino acids come in two mirror image shapes (like the left and right hand). The team will continue working to unravel the origin of Bennu and the beginnings of our solar system.
With information from EFE.
