06/12/2026
The claim that Voyager 1 will reach a distance of one light-day from Earth by year-end is true. A light-day is the distance that light travels in 24 hours—about 25.9 billion kilometers (16.1 billion miles). After nearly five decades of travel, Voyager 1 is approaching this remarkable milestone.
Launched in 1977, Voyager 1 has traveled farther from Earth than any other human-made object. It crossed into interstellar space in 2012 and continues to send scientific data back to Earth, despite being powered by aging systems and operating in one of the most remote environments ever explored by a spacecraft.
When a signal is sent from Earth to Voyager 1, it now takes nearly a full day for the radio message to reach the spacecraft. Likewise, a response takes almost another day to return. This means communications with Voyager involve delays approaching two days for a complete exchange.
Ultimately, reaching a distance of one light-day is a powerful reminder of both Voyager's incredible journey and the immense scale of space. Even after traveling for decades at tens of thousands of kilometers per hour, humanity's most distant spacecraft has covered only a tiny fraction of the distance to the nearest stars.