Overview
- Researchers reported in Nature Astronomy on July 13 that they identified the four‑carbon sugar erythrulose in the molecular cloud G+0.693−0.027 near the galaxy’s center.
- The detection rests on radio observations from Spain’s Yebes 40‑m and IRAM 30‑m telescopes matched to laboratory spectra with 12 matching line sets and six largely unblended lines giving a roughly 0.2% chance of random alignment.
- Quantum‑chemical calculations and astrochemical models in the paper show a plausible route in which two‑carbon molecules react on icy dust grains and are released to the gas phase by radiation or shocks.
- Authors estimate that between about 0.5 million and 55 million tonnes of erythrulose could have reached early Earth during the Late Heavy Bombardment but note that those delivery totals depend on debated assumptions about bombardment intensity.
- The finding challenges simple stepwise carbon‑addition views of interstellar chemistry because a four‑carbon sugar appears more abundant than expected smaller sugars, and it builds on earlier discoveries of extraterrestrial sugars in meteorites and returned asteroid samples.