Earthlife is made of space stuff, studies of asteroid Bennu hint, Pg11

Key Highlights:

• In 2020, NASA's OSIRIS-REx mission collected surface samples from the asteroid Bennu, delivering them to Earth in September 2023.
• Studies of Bennu revealed the presence of ribose and glucose, essential sugar molecules for RNA and metabolism.
• Scientists confirmed the existence of all molecules believed necessary for life on Bennu, including amino acids and all five nucleobases.
• Bennu contains a surprisingly high amount of supernova dust from before the Sun's formation.
• Researchers found evidence of chemical reactions between ices that formed polymer molecules on Bennu.
• The concentration of presolar grains on Bennu is at least six times higher than in other similar asteroid and meteorite samples.

Detailed Insights:

• Bennu's parent asteroid formed around 4.6 billion years ago, beyond Saturn, and was later displaced into the asteroid belt due to Jupiter's migration.
• The discovery of sugars on Bennu supports the 'RNA world' hypothesis, suggesting that early life used RNA for genetic information before DNA and proteins evolved.
• Carbamate, a nitrogen- and oxygen-rich material, was found on Bennu, marking the first time this material has been identified in extraterrestrial samples.
• Volatile compound ices on Bennu's parent asteroid could have liquefied due to radioactive decay, depositing salts and minerals in rocky pores.
• Analysis of presolar grains on Bennu indicates they originated from various types of stars and supernovae, with the latter being particularly abundant.
• The abundance of supernova-origin presolar grains on Bennu raises questions about whether this is unique to Bennu or common among asteroids.

Scientific/Technical Concepts Involved:

• RNA (Ribonucleic Acid): A molecule similar to DNA that is essential in various biological roles in coding, decoding, regulation and expression of genes.
• Amino Acids: Organic compounds that contain amino and carboxyl functional groups, which are the building blocks of proteins.
• Supernova: A powerful and luminous explosion of a star.
• Presolar Grains: Solid matter that formed before the Sun and the Solar System.