Voyager 1 will reach 25.9 billion kilometers from Earth on November 18, becoming the first human-made object to cross a one light-day distance.
Launched by NASA in September 1977 from Cape Canaveral, Florida, aboard a Titan IIIE-Centaur rocket, the spacecraft is traveling through interstellar space at roughly 61,000 kilometers per hour. That extreme separation means a radio signal sent from Earth takes 24 hours to reach the probe, and another 24 hours for a response to return.
“I just never imagined [the mission] would last that long,” Linda Spilker, a planetary scientist at NASA's Jet Propulsion Laboratory (JPL), told Science News.
Teams also resolved an unexpected loss of communication with Voyager 1 when the Deep Space Network did not detect the probe’s signal during two scheduled comms passes. Contact was reestablished on Oct. 20, and the team has maintained communication since then.…
Engineers replaced Voyager 1 devices to save power
Maintaining contact across deep space relies on NASA’s Jet Propulsion Laboratory and the global antennas of the Deep Space Network. Both Voyager probes carry a nuclear power plant on board that utilizes decaying plutonium.
In September, engineers completed an energy-saving operation called the Big Bang, which replaced three devices on Voyager 1 with equipment capable of operating with lower energy consumption. Alan Cummings, a senior researcher at Caltech’s Space Radiation Laboratory and a Voyager program scientist since 1973, described the event as an engineering milestone.
No other traveler has ever journeyed so far from home. Voyager 1 is about to become the first human-made object to reach a distance of one light-day from Earth, or about 16 billion miles. ½ pic.twitter.com/uETo8DHUF1
Operational challenges extend beyond declining electrical output. Contact was successfully restored after a 48-hour communication loss.
Decades of planetary exploration
Voyager 1 crossed the heliopause in August 2012, entering interstellar space, while Voyager 2 crossed that boundary in November 2018 after flying past Uranus and Neptune.
Along their trajectories, the probes recorded storms in Jupiter, identified volcanic activity on Jupiter’s moon Io, discovered two previously unknown Jovian moons named Thebe and Metis, found five new moons and a new ring named the G ring around Saturn, and captured the iconic 1990 image of Earth known as the Pale Blue Dot.
NASA expects Voyager 2 to reach the same one light-day milestone in November 2035. Meanwhile, Voyager 1 continues its journey toward the star Gliese 445.
Earlier coverage: Voyager 1 to Reach One Light-day From Earth, NASA Data Shows