Voyager 1: Humanity's Most Distant Spacecraft

What is Voyager 1?

Voyager 1 is a space probe launched by NASA on 5 September 1977. It is part of the Voyager programme, which also includes its twin, Voyager 2. The primary mission of Voyager 1 was to explore the outer planets of our solar system, specifically Jupiter and Saturn, and it has since become the first human-made object to enter interstellar space. It still sends data back to Earth from beyond the heliosphere, the bubble of solar wind that marks the Sun's influence, and its live distance, speed and signal time are on our Voyager 1 tracker. On 18 November 2026 it becomes the first spacecraft one light-day from Earth.

Mission and Purpose

Voyager 1's mission was to conduct close-up studies of Jupiter and Saturn, their moons, and rings. The spacecraft provided the first detailed images of these planets and discovered active volcanoes on Jupiter's moon Io, as well as complex structures in Saturn's rings. After completing its primary mission, Voyager 1 continued on a trajectory that eventually took it into interstellar space, where it now studies the interstellar medium (the matter and radiation that exists in the space between the star systems in a galaxy).

Orbital Characteristics

Voyager 1 is not in orbit around any celestial body but is on a hyperbolic trajectory out of the solar system. It is travelling at about 17 km/s (61,000 km/h) relative to the Sun and is more than 25 billion kilometres from Earth, making it the most distant human-made object. Its trajectory is directed towards the constellation Ophiuchus, and it is expected to pass within 1.6 light-years of the star Gliese 445 in about 40,000 years.

Significance and Legacy

Voyager 1 has provided humanity with some of the most detailed images and data of the outer planets and their moons. Its journey into interstellar space marks a significant milestone in space exploration, expanding our understanding of the solar system's boundary. The spacecraft carries a Golden Record, a phonograph record containing sounds and images selected to portray the diversity of life and culture on Earth, intended as a message to any extraterrestrial life that might encounter it.

Current Status

Voyager 1 still works, although its plutonium power supply loses about 4 watts a year. To save energy, NASA has switched off all but two of its science instruments, the magnetometer and the plasma wave instrument, and expects at least one to keep working into the 2030s. At its distance, its signals take about a day to reach Earth. Its live position, speed and signal time are on Orbital Radar's Voyager 1 tracker.