Quo Vadis, Voyager 2?

By Ines Wynn


Are you wondering what happened to the Voyager interstellar space probes and their encoded message to the aliens? We never seem to get any interesting updates so it took a bit of googling to get an idea of their present location and state of existence.

As of today there are 2 Voyager probes wandering around in space, Voyager 1 and Voyager 2, both launched by NASA in the summer of 1977 within a couple of weeks from each other with a mission to explore the outer planets whose orbit lies outside the asteroid belt, i.e., Jupiter, Saturn, Uranus and Neptune. The goal of this interstellar mission of the Voyagers was to extend the NASA exploration of the solar system and conduct close-up studies of Jupiter and Saturn, Saturn’s rings, and the larger moons of the two planets. Their extended mandate was to go beyond the outer planets to the far limits of the solar system, and possibly beyond. The Voyagers are capable of leaving the solar system and enter interstellar space; they are capable of reaching other star systems.

Voyager 2 was the first probe to be launched on 20 August 1977 and visited Jupiter in 1979, Saturn in 1981 and Uranus in 1986 before making its closest approach to Neptune on 25 August 25 1989. It was launched first because its programmed trajectory would take longer to reach Jupiter and Saturn but enabled further encounters with Uranus and Neptune. Voyager 1 departed on 5 September 1977 and would mainly concern itself with Jupiter and Saturn, along a shorter and faster trajectory that was designed to provide an optimal flyby of Saturn’s moon Titan.

The Voyagers launch date was chosen to take advantage of a cosmic alignment that happens only once every 176 years when the planets had to be arranged in just the right way to enable the probes to make the grand tour of our outer solar system by using gravitational assists to explore Jupiter, Saturn, Uranus, Neptune, and Pluto. Although at the time it was expected that the journey would end at Saturn, NASA engineers were able to design the spacecraft to last at least until Neptune – and beyond.

The Voyagers are equipped with cameras, magnetometers and diverse scientific instruments. The probe’s communication system includes a parabolic dish antenna, with a 3.7 meter diameter to send and receive radio waves via the Deep Space Network stations on Earth. A signal from the Voyagers at the speed of light takes 17 hours to reach Earth.

Like most technology powered robotics of that time, they have less computing power than a modern hearing aid. Yet they were able to take astonishing close-up pictures of the planets they visited and helped unlock some stunning secrets of our solar system on their journey. The twin space probes sent back heretofore unseen images of swirling gas giants Jupiter and Saturn, ice giants Uranus and Neptune and their new and exotic moons, some with atmospheres and bubbling ice volcanoes.

Their encounters revealed unknown details about each of the four giant planets and their moons. Close-up images from the spacecraft charted Jupiter’s complex cloud forms, winds and storm systems and discovered volcanic activity on its moon Io. Saturn’s rings were found to have enigmatic braids, kinks and spokes and to be accompanied by myriad ‘ringlets’. At Uranus, Voyager 2 discovered a substantial magnetic field around the planet and ten more moons. Its flyby of Neptune uncovered three rings and six hitherto unknown moons, a planetary magnetic field and complex, widely distributed auroras. Voyager 2 is the only spacecraft to have visited the two ice giants Uranus and Neptune.

Where are they now? Today Voyager 1 is more than 13 billion miles away and left our solar system in August 2012 to enter the void of deep interstellar space, some 35 years after its launch in 1977. It is the first man-made object ever to do so, moving with a velocity of 17 km per second. It has been on the cosmic road for a total of 41 years and is headed to a star called Alpha Centauri, a mind boggling 17.6 light years from earth. It will get there in another 70.000 years. Voyager 2 is not far behind, though on a different trajectory and in 296.000 years from now it will be passing within 4.6 light years of Sirius which is the brightest star in the night sky.

The famous gold record – Both Voyagers are carrying two phonograph records bearing recordings and images of life on Earth along with symbolic directions on the cover for playing the record and data detailing the location of Earth. Each record is a 30 cm gold-plated copper disk and, like a time capsule, contains sounds and images selected to portray the diversity of life and culture on Earth – as of 1977. The discs contain photos of Earth and its life forms, a range of scientific information, spoken greetings in 55 languages from Earth’s people (e.g. the Secretary-General of the United Nations and the President of the United States, and the children of the Planet Earth) and a medley called “Sounds of Earth” that includes the sounds of whales, a baby crying, waves breaking on a shore, and a collection of music, including works by Mozart, Blind Willie Johnson, Chuck Berry’s “Johnny B. Goode”, Valya Balkanska and other Eastern and Western classics and ethnic performers.

The End – Though their primary mission ended in1989, the Voyagers are still dashing brazenly further into deep space and continue to operate, recording and sending scientific data back to Earth with their primitive instruments. They have adequate electrical power to run science instruments until around 2025. At that time science data communications and spacecraft operations will cease and the probes will become silent voyagers in the void. Voyager 2 has enough fuel to keep going until 2034, while Voyager 1 can keep hurtling along until 2040.

They have been out there for 41 years and like the famous bunny, will be going… and going until the lights go out. The golden records will be there for eternity, until some alien being or intelligent power finds them and wonders if our planet Earth is still in existence. And no, no-one has called yet.

Photos and information borrowed from Wikipedia with grateful thanks.