Is the Sun going to enter a million-degree galactic cloud of interstellar gas soon? Scientists from the Space Research Centre of the Polish Academy of Sciences, Los Alamos National Laboratory, Southwest Research Institute, and Boston University suggest that the ribbon of enhanced emissions of energetic neutral atoms, discovered last year by the NASA Small Explorer satellite IBEX, could be explained by a geometric effect coming up because of the approach of the Sun to the boundary between the Local Cloud of interstellar gas and another cloud of a very hot gas called the Local Bubble. If this hypothesis is correct,...