In a groundbreaking discovery, the Voyager probes have detected a hot plasma wall at the edge of our solar system, marking the transition to interstellar space. This finding provides new insights into the heliopause and the sun's influence.
Launched in 1977, Voyager 2 crossed the heliopause and entered interstellar space on November 5, 2018. The probes encountered an unexpected "firewall" of plasma at the heliopause, the boundary between our solar system and interstellar space. This plasma wall has temperatures reaching up to 50,000 Kelvin (approximately 89,000 degrees Fahrenheit). This region is sometimes referred to as the "wall of fire".
This discovery is crucial for understanding how our solar system shields itself from cosmic radiation. The heliopause acts as a protective barrier, deflecting a significant portion of harmful interstellar radiation. The extreme temperature of the plasma wall does not pose a direct threat to spacecraft due to its low density, but it is a significant factor for future interstellar missions. Any spacecraft venturing beyond our solar system must traverse this zone.
Voyager 1 entered interstellar space on August 25, 2012. The Voyager program continues to provide valuable data on the structure of the interstellar medium. The Voyager probes are the only two functioning spacecraft currently in interstellar space, and they are still sending back measurements.