Jobin Cyriac

In a cold cloud of gas and dust that astronomers call TMC-1, two sulfur-bearing compounds were recently found: one smells like bitter almonds, the other like rotten eggs. But such a cloud contains less sulfur than it should. Where does it go? It seems to hide in tiny icy pockets on the surface of dust grains. Space ice is not like a skating rink. It is fluffy, like snow, and full of crevices and hollows.

A chemical reaction resembles passing through a turnstile: a crowd creates chaos and gets stuck, while an orderly line moves. In the quantum world, however, when the jostling subsides, the barrier can become ghostly — a particle passes through it as if the turnstile has vanished.