On Nov. 5, 2018, Voyager 2 became the second spacecraft to enter interstellar space, as it passed through the heliosphere’s outer limit, known as the heliopause, NASA announced at the American Geophysical Union (AGU) fall meeting in Washington, D.C., on Monday. The spacecraft’s twin, Voyager 1, made history as the first man-made object to depart the heliosphere in 2012. Reaching interstellar space is an extraordinary feat for spacecraft that have been traveling for more than 41 years.