The most distant human-made object
Voyager 1
Voyager 1 left Earth in September 1977 on a tour of the giant planets. After revealing Jupiter and Saturn in unprecedented detail, it kept going — and in 2012 it became the first spacecraft to cross the heliopause, the boundary where the Sun's influence gives way to interstellar space.
Nearly half a century after launch it is still sending data home across more than 170 astronomical units, a distance light takes about a day to cross.
Key facts
- Agency
- NASA / JPL
- Launched
- 1977-09-05
- Launch vehicle
- Titan IIIE–Centaur
- Power
- Radioisotope thermoelectric generators (plutonium-238)
- Mission type
- Flyby, then interstellar mission
- Twin
- Voyager 2
- Status
- Operating in interstellar space with a reduced set of instruments to conserve power
Where it is now
Loading live position from NASA/JPL Horizons…
Interstellar space. In about 40,000 years it will pass within about 1.6 light-years of the star Gliese 445.
Mission objectives
Voyager 1 and its twin were designed to take advantage of a rare alignment of the outer planets that allowed gravity assists from one world to the next. Voyager 1 followed a faster route to Jupiter and Saturn, with a close pass of Saturn's large moon Titan as a priority target.
Since leaving the planets behind, its Voyager Interstellar Mission has been to study the outer heliosphere and the interstellar medium beyond it.
The spacecraft
Too far from the Sun for solar panels, Voyager 1 is powered by radioisotope thermoelectric generators that turn the heat of decaying plutonium-238 into electricity. Their output falls a little every year, so engineers have gradually switched off heaters and instruments to keep the most important ones running.
The Golden Record
Both Voyagers carry a gold-plated copper phonograph record with sounds and images of Earth — greetings in 55 languages, music from many cultures and natural sounds — intended as a message for any spacefaring civilisation that might one day find it.
Talking to home
Its signals, transmitted with about the power of a refrigerator light bulb, are received by NASA's Deep Space Network of giant antennas in California, Spain and Australia.
Discoveries and highlights
At Jupiter, Voyager 1 discovered active volcanoes on the moon Io — the first seen anywhere beyond Earth — and a thin ring around the planet. At Saturn it revealed intricate structure in the rings and showed that Titan has a thick, hazy nitrogen atmosphere.
In 1990 it turned its camera back to take the 'Family Portrait' of the planets, including the famous 'Pale Blue Dot' image of Earth from about 6 billion km away.
Route and timeline
- 1977-09-05Launch, Cape Canaveral
- 1979-03-05Jupiter flyby
- 1980-11-12Saturn and Titan flyby
- 1990-02-14'Pale Blue Dot' image of Earth
- 2012-08-25Crossed the heliopause into interstellar space
Surprising facts about Voyager 1
- Voyager 1 is moving away from the Sun at about 17 km/s.
- Each Voyager's onboard computers have only about 69 kilobytes of memory.
- A radio signal from Voyager 1 now takes roughly a day to reach Earth.
- It overtook Pioneer 10 as the most distant spacecraft in 1998.