James Webb Telescope Discovers Building Blocks of Life in Nearby Galaxy

For the first time, scientists have discovered five complex carbon-based organic molecules in the ice surrounding a protostar in the Large Magellanic Cloud, the most massive satellite galaxy of the Milky Way located 160,000 light-years from Earth. The discovery was reported by Live Science, citing a study published in The Astrophysical Journal Letters.

James Webb Telescope Unveils Molecular Ice

In spring 2024, researchers aimed the James Webb Space Telescope at the forming star ST6 in the Large Magellanic Cloud. Using infrared instruments, they identified five carbon-based molecules in the surrounding ice: methanol, acetaldehyde, ethanol, methyl formate, and acetic acid. These compounds are considered the building blocks of life, as they serve as precursors for more complex organic molecules such as amino acids, sugars, and nucleotides—the foundations of proteins, DNA, and RNA.

Significance for Astrobiology

These molecules, including various alcohols, aldehydes, and acids, can chemically combine under certain conditions into long chains and complex structures, making them essential precursors for life. According to Martha Sevilio, an astronomer at the University of Maryland and co-author of the study, prior detections of complex organic molecules in protostars beyond the Milky Way included only methanol. Notably, acetic acid had never before been observed in cosmic ice.

The researchers also detected signals potentially indicating the presence of glycolaldehyde, a molecule that forms one of the components of RNA. Further studies are needed to confirm its presence in the protostellar ice.