Spatial archaeology examines rock samples from space missions, notably NASA’s Osiris-Rex, which collected materials from asteroid Bennu in 2020. Initial analyses in 2023 revealed key elements for life, including water crystals and amino acids. These findings suggest that life on Earth may have originated from extraterrestrial sources, while also hinting at unique compounds not found on our planet. The implications extend to potential life-supporting environments on moons and dwarf planets within our solar system.
Exploring the Exciting Field of Spatial Archaeology
Spatial archaeology is an innovative field that focuses on analyzing rock samples returned to Earth by space missions. This burgeoning discipline gained significant attention after NASA’s Osiris-Rex probe successfully gathered 250 grams of dust and debris from the surface of an asteroid named Bennu in 2020. This remarkable feat took place approximately 300 million kilometers from our planet and involved a complex series of operations. After three years of travel through space, the spacecraft released a capsule containing these invaluable samples above Earth.
Revelations from Asteroid Bennu: The Building Blocks of Life
In 2023, initial analyses of the samples revealed exciting findings, including the presence of water crystals and carbon—two fundamental elements critical for creating complex life-form molecules. In a study published in January in the journal Nature Astronomy, NASA astrobiologist Daniel Glavin and astrochemist Jason Dworkin reported the detection of 14 out of the 20 amino acids essential for protein synthesis in Earthly life. They also identified five bases crucial for forming DNA and RNA, which are vital for the biological processes that support life as we know it.
This groundbreaking discovery raises intriguing questions for those who support the theory that life on Earth may have originated from asteroids or comets carrying the necessary components from beyond our solar system. Nonetheless, it does not rule out the possibility that life could have emerged from the primordial oceans or even from Earth’s atmosphere. Bennu’s samples contained a greater variety of compounds than those typically found on Earth, including rare amino acids that do not exist on our planet, as well as thousands of nitrogenous compounds whose origins remain a mystery.
According to a follow-up study published in the journal Nature, the origins of these unique compounds can be traced back to Bennu’s “parent” body—a larger celestial body that formed less than 65 million years ago, dating back to the early stages of our solar system, approximately 4.5 billion years ago. Tim McCoy, curator of the mineral collection at the Smithsonian National Museum of Natural History and the study’s lead author, explains that the inorganic compounds found in Bennu likely resulted from evaporating water pockets within its parent body.
The study suggests that the water from which Bennu originated contained both organic and inorganic compounds that underwent chemical reactions to create biological molecules. This is further substantiated by the discovery of brines resembling salt crusts found in Earth’s dried lakes, with samples from Bennu containing six minerals similar to those located in Searles Lake, California.
This discovery is particularly significant, as brine environments could provide the ideal conditions for life to evolve or even sustain itself within our solar system. The study highlights the potential for such environments on moons like Enceladus, orbiting Saturn, and on the dwarf planet Ceres, found in the asteroid belt between Mars and Jupiter. These findings not only offer vital insights into the origins of life on Earth but also pave the way for future space exploration missions targeting these intriguing locations.