Voyager's barely-there interstellar whisper still reaches Earth

Even after more than four decades, Voyager 1's transmitter—powering a signal the strength of a household bulb—remains audible on Earth as an ultra-weak whisper. NASA's Deep Space Network and enhanced ground systems extract data about the heliopause and local interstellar medium from this fading signal, which travels tens of billions of kilometers and requires a round-trip of nearly two days. The probes’ aging hardware has forced engineers to repair and adapt memory and power management over the years, and while the plutonium power source will eventually silence the link, for now Voyager persists as a faint but scientifically valuable bridge to the edge of the solar system.