Scientists Detect Sugar Molecule in Galactic Cloud

Overview

• The research team led by Izaskun Jiménez-Serra reported Tuesday that they identified the four-carbon sugar erythrulose in the molecular cloud G+0.693−0.027 by matching lab-measured rotational spectra to radio data from the Yebes 40-m and IRAM 30-m telescopes.
• The identification rests on 12 matching line groups (17 rotational transitions) with six relatively uncontaminated sets and a quoted 0.2% chance that the clearest signals are random coincidences.
• Erythrulose is a ketose with four carbon atoms and 14 atoms total, making it the largest non-cyclic molecule confirmed so far in the free interstellar medium.
• Quantum-chemical calculations and astrochemical models in the study indicate the molecule likely forms on amorphous water-ice surfaces of interstellar dust from two-carbon precursors such as glycolaldehyde and ethylene glycol, and it appears at least eight times more abundant there than similar three-carbon sugars.
• Researchers caution that abundance estimates and implications for the origin of life depend on model assumptions and further observations, but the find strengthens the case that some prebiotic molecules formed in space and motivates searches for other biologically relevant sugars such as ribose.