Precursors of the RNA-world in space: Detection of ($Z$)-1,2-ethenediol in the interstellar medium, a key intermediate in sugar formation

TL;DR

This paper reports the first detection of ($Z$)-1,2-ethenediol in the interstellar medium, suggesting its role as a key intermediate in sugar formation and providing insights into prebiotic chemistry in space.

Contribution

The study presents the first identification of ($Z$)-1,2-ethenediol in space and explores its formation pathways and significance in prebiotic molecule synthesis.

Findings

Detected ($Z$)-1,2-ethenediol with a column density of 1.8×10^13 cm^-2.

Found an abundance ratio of ~5.2 between glycolaldehyde and ($Z$)-1,2-ethenediol.

Proposed formation routes and its role as a precursor to glyceraldehyde.

Abstract

We present the first detection of ($Z$)-1,2-ethenediol, (CHOH)$_2$, the enol form of glycolaldehyde, in the interstellar medium towards the G+0.693-0.027 molecular cloud located in the Galactic Center. We have derived a column density of (1.8$\pm$0.1)$\times$10$^{13}$ cm$^{-2}$, which translates into a molecular abundance with respect to molecular hydrogen of 1.3$\times$10$^{-10}$. The abundance ratio between glycolaldehyde and ($Z$)-1,2-ethenediol is $\sim$5.2. We discuss several viable formation routes through chemical reactions from precursors such as HCO, H$_2$CO, CHOH or CH$_2$CHOH. We also propose that this species might be an important precursor in the formation of glyceraldehyde (HOCH$_2$CHOHCHO) in the interstellar medium through combination with the hydroxymethylene (CHOH) radical.