Life's chemistry may begin in the cold darkness of space

Scientists at Aarhus University have found that peptides, the precursors to proteins, can form on interstellar dust grains under conditions that mimic deep space. Experiments in a specialized chamber reproduced temperatures of about minus 260 degrees Celsius and ultra-high vacuum in regions thousands of light-years from Earth, along with exposure to radiation similar to cosmic rays. The team, led by Sergio Ioppolo and Alfred Thomas Hopkinson, placed glycine in the chamber and observed it reacting to create peptides and water. The work also drew on an ion accelerator at a research facility in Hungary. This process challenges earlier views that only simple molecules form in star-forming clouds and that more complex chemistry occurs later in denser discs. The results suggest that key building blocks of life arise naturally in these environments before planets exist. The chemical reaction follows the same basic rules for all types of amino acids. Co-author Liv Hornekær noted that other molecules important for life may participate in similar reactions. The study was published in Nature Astronomy.