Reacción a "Sugar has been detected in interstellar space by the radio telescopes at Yebes in Guadalajara and Pico Veleta in the Sierra Nevada"

Finding a sugar in the interstellar medium may seem impossible. However, an international team has succeeded in detecting a sugar in space for the first time: erythrulose, a four-carbon monosaccharide, in a molecular cloud situated near the centre of our galaxy, known as G+0.693−0.027. How is it possible to identify a molecule at such an enormous distance? Just like a fingerprint, every molecule has a distinctive signature that allows it to be identified. In this case, that signature is its rotational spectrum: the set of microwave frequencies associated with the molecule’s rotation and characteristic of each molecular structure. To identify erythrulose, it was essential to first obtain this spectrum in the laboratory.

This was a considerable challenge, as this molecule readily absorbs water from the environment and decomposes when heated. The authors overcame this difficulty using an innovative vapourisation technique involving ultrafast laser pulses, which enabled them to record its rotational spectrum in the gas phase for the first time. The identification was corroborated by quantum chemical calculations and astrochemical models showing a chemically plausible formation pathway on the ice coatings of interstellar dust grains. Surprisingly, erythrulose is at least eight times more abundant than similar three-carbon sugars, which were not detected despite the study’s extremely high sensitivity.

It should be noted that this does not imply that erythrulose reached Earth or played a role in the origin of life; its significance lies in demonstrating that interstellar chemistry can generate molecules of increasing complexity, by combining astronomical observation, laboratory spectroscopy and theoretical chemistry.