Scientists are now probing interstellar ices for the earliest signs of life’s components, a study reveals, potentially reshaping theories about how life began on Earth and elsewhere in the universe.
Research indicates that amino acids, vital for life, could have emerged alongside stars and planets in the frigid realms of outer space, offering new insights into the quest for life’s origins.
Geologically, Earth’s life is a recent phenomenon, but the components that led to its formation could be far older than previously believed.
Recent findings published in ACS Central Science suggest that carbamic acid, a basic amino acid, might have originated in the icy realms surrounding newborn stars or planets.
These discoveries could guide the calibration of advanced space exploration tools like the James Webb Space Telescope in their quest to detect prebiotic molecules in remote, star-forming areas of the universe.
The prevailing theory has been that life’s building blocks, such as amino acids, emerged from the chemical reactions in Earth’s early “primordial soup.” An alternative hypothesis proposes these amino acids might have been brought to Earth via meteorites, which collected them from cosmic dust or interstellar ices – substances frozen in the extreme cold of space.
Given the extraterrestrial origin of these meteorites, the question arises about the initial formation and timing of these molecular structures.
To explore this, a team led by Ralf Kaiser and Agnes Chang conducted experiments on simulated interstellar ices, composed of ammonia and carbon dioxide, and observed their reactions when gradually heated on a silver surface.
Through Fourier transform infrared spectroscopy, they discovered the formation of carbamic acid and ammonium carbamate at extremely low temperatures of -348 and -389 degrees Fahrenheit (62 and 39 Kelvin, respectively).
This indicates that these molecules, precursors to more complex amino acids, likely formed during the coldest, initial phases of star and planet formation. Additionally, the team noted that at higher temperatures, akin to those near newly formed stars, carbamic acid molecules could combine to form a stable gas.
The researchers theorize that such molecules could have been integral to the development of solar systems, including our own, and eventually reached early Earth via comets or meteorites.
This research paves the way for future astronomical studies using powerful telescopes to seek signs of prebiotic molecules in the vast expanse of space.
Source: 10.1021/acscentsci.3c01108
Image Credit: iStock
