The Voyager 2 interstellar space probe was launched on August 20, 1977. Its counterpart, Voyager 1, was launched sixteen days later. The second probe traveled at a greater speed, arriving at Jupiter nearly four months earlier.
Each probe used the gravitational force of the planets it passed to increase it’s velocity, an innovation in aerospace engineering called “gravity assist” that was experimental at the time of their launch. This and the extraordinary alignment of the solar system’s outer planets in the late 1970s (something that will not occur again until well into the next century) allowed them to tour the “gas giants” with leisure and send back to Earth some of the most breathtaking images ever captured by a camera.
The probes have long since completed their primary missions – Voyager 1 left the Saturnian system in 1980, and Voyager 2, which took a much longer trip through the solar system, left the Uranian system in 1986, and bid farewell to cold and distant Neptune in 1989. Propelled like slingshots by the massive gravitational force of the gigantic planets, the Voyager probes continue to move away from our sun. Their secondary mission is to explore interstellar space.
Voyager 1 is presently more than eighteen billion kilometers from Earth, the farthest-away man-made object cast into space. Voyager 2, is a little closer, only fifteen billion kilometers from us, and moving in a different direction. According to NASA’s official site for the Voyager interstellar mission (here) they are both in a region called the heliosheath, the outer-most layer of of our heliosphere, where solar wind is slowed by pressure from interstellar gas.
After it becomes the first man-made object to leave our solar system, Voyager 1 will continue to drift away from us without stopping, a predicted by Sir Isaac Newton’s law of inertia (“an object at motion will continue in motion and at the same speed unless acted upon by an unbalanced force”). In the year 40,272 AD, the probe will come within 1.7 light years of an unnamed star in the Ursa Minor constellation known simply as AC+79 3888.
Voyager 2‘s destination is more desolate. It will pass within 4.3 light years of Sirius (the Dog Star) in about the year 302,000 AD. This is about the same distance as exists between our Sun and the nearest neighboring star, Proxima Centauri.
Both probes are expected to lose all power in or around 2025. And while there seems to be little chance they will encounter an extrasolar planet (a planet outside of our solar system) or an intelligent being, it cannot be assumed with certainty that they will not. Perhaps somewhere in that unfathomably vast void there are beings scanning for signs of life, just as we have done for decades (just ask these people). And this, for those of you still reading, is why we are talking about space probes launched thirty-five years ago on the Hymie’s blog.
There are records on the Voyager probes.
The cover of each record contains binary instructions (upper left and center left) showing how quickly the record must turn and how the stylus must be elevated. It also contains binary instructions that explain how to produce the video images encoded in analog form (upper right and center right). The hydrogen atom (lower right) appears for reference, and to it’s left is an image presenting the location of our solar system.
Each record comes with a mounting platter as well as a cartridge and needle. The records are made of copper and plated with gold.
They open with a greeting, spoken in English, by Kurt Waldheim, Secretary General of the United Nations in 1977. This is followed by additional greetings in 55 different languages (including four dialects of Chinese, five ancient languages and Esperanto, but sadly none representing indigenous American people). This is followed by a collections of sound from Earth, ranging from Johannes Keplar’s “Harmonicies Mundi” to animal and bird sounds to the launch of a Saturn V rocket.
The third section of the audio portion represents the music of Earth. It begins with the first movement of Bach’s Brandenberg Concerto no. 2 and then becomes one of the strangest mix tapes ever given to someone on a first date. A pygmy girls’ song from Zaire and percussion from Senegal is included alongside Shakuhachi music from Japan and an aria from Mozart’s Magic Flute.
Bach’s music appears three times, and the people of the United States are represented four times (we should be since we paid for the record and the rocket that launched it!). Chuck Berry’s “Rock and Roll Music” is probably the most contemporary piece on the album, although the NASA committee that created it requested permission to include the Beatles’ “Here Comes the Sun” (it was denied by their short-sighted record label, EMI). Also representing American culture are recordings of Louis Armstrong and his Hot Five, a Navajo night chant, and blues singer Blind Willie Johnson.
There were a number of criticisms of the golden records, notably for their emphasis on American and western European music. Others were offended that the images portion contained images of a naked man and woman, which had been a problem with the plaques attached to Pioneer 10 and 11.
An on-going and remarkable criticism of the golden records is that they shouldn’t have been included in the probes at all. Stephen Hawking pointed out that “if aliens visit us, the outcome would be much as when Columbus landed in America, which didn’t turn out well for the Native Americans,” arguing against sending anything out of the solar system that might include directions to our planet (this was widely reported at the time, you can read it here). He pointed to the historical precedence set by encounters between advanced and less advanced societies.
That humankind could face such a catastrophic end out of HG Wells is very unlikely, given the rare chance the Yoyager probes will ever be seen. Each will stop emitting any kind of electromagnetic energy about ten to twenty years after they lose power, making them tiny specks floating anonymously in an almost inconceivably vast empty space. Folks often come into the record shop here and say they’ve heard records are coming back — well, here are two records that most certainly aren’t.