Voyager 2 Joins Its Twin in Interstellar Space

The probe crossed the heliopause, the boundary between the heliosphere and the interstellar medium, on November 5.


We May Have Identified What Lies at the Outermost Edge of Our Solar System

New Horizons is the first spacecraft in nearly three decades to observe what appears to be evidence of a hydrogen wall at the edge of the heliosphere.


Heather Christle’s ‘Heliopause’ Disintegrates Reality

Christle's latest collection of poetry is a book easily larger than the sum of all its parts; it widens the rift between fantasy and reality in a way that makes the world somehow both clearer and more mysterious.