NASA's Voyager 1 is expected to cross the one-light-day mark on November 18, 2026, 49 years after its launch, at a distance of 16.1 billion miles from the Sun, according to the agency's night sky notes. At the time of the article, the Canberra antenna was tracking Voyager 1 at 25.80 billion km, or just over 16 billion miles.

Voyager 1 and 2 launched in 1977, using a once-every-175-year alignment of Jupiter, Saturn, Uranus and Neptune. Six gravity assists carried the twin craft past the gas and ice giants and several moons. The probes separated at Saturn in the 1980s; Voyager 2 went on toward Uranus and Neptune, while Voyager 1 captured a final portrait of the solar system that included the Pale Blue Dot image of Earth. Voyager 1 crossed the heliopause in August 2012 and Voyager 2 in November 2018. Both craft still return science data and are tracked through NASA's Deep Space Network.

Each craft carries a Golden Record, a 12-inch phonograph record with greetings in 55 languages, 27 musical tracks, 116 images and other Earth sounds. Its aluminum cover is electroplated with uranium-238, an isotope with a half-life of 4.468 billion years.