When the four-decades-old Voyager 1 and Voyager 2 spacecraft entered interstellar space in 2012 and 2018, respectively, scientists celebrated. These plucky spacecraft had already traveled 120 times the distance from the Earth to the sun to reach the boundary of the heliosphere, the bubble encompassing our solar system that’s affected by the solar wind. The Voyagers discovered the edge of the bubble but left scientists with many questions about how our Sun interacts with the local interstellar medium. The twin Voyagers’ instruments provide limited data, leaving critical gaps in our understanding of this region.
NASA and its partners are now planning for the next spacecraft, currently called the Interstellar Probe, to travel much deeper into interstellar space, 1000 astronomical units (AU) from the sun, with the hope of learning more about how our home heliosphere formed and how it evolves.
“The Interstellar Probe will go to the unknown local interstellar space, where humanity has never reached before,” says Elena Provornikova, the Interstellar Probe heliophysics lead from the Johns Hopkins Applied Physics Lab (APL) in Maryland. “For the first time, we will take a picture of our vast heliosphere from the outside to see what our solar system home looks like.”
