space Nature Is Weird

Some molecules in deep space are 'lefties' or 'righties,' and the weird part is they totally ignore the normal laws of heat and energy.

March 27, 2026

Original Paper

Interstellar stereoisomerism

Víctor M. Rivilla, Miguel Sanz-Novo, David San Andrés

arXiv · 2603.24848

The Takeaway

Normally, the temperature in space dictates which molecular shapes should exist in a cloud, but researchers found that certain versions are far more common than thermodynamics allows. This suggests a mysterious, selective chemical process is at work in the void, potentially linked to the same 'handedness' that makes life on Earth possible.

From the abstract

The increasing detection of new molecules in the interstellar medium (ISM) shows that stereoisomerism is a fundamental contributor to interstellar molecular complexity. This work presents the first comprehensive overview of interstellar stereoisomerism. A total of 16 stereoisomeric pairs have been identified (13 conformational and 3 geometric), spanning molecules with 5-12 atoms and energy separations from 10 K to 2667 K. They were observed across diverse astrophysical environments with kinetic