35 years, and both Voyager and I are still running


By Bob McDonald, Quirks & Quarks

35 years ago this week, sporting black hair down to my shoulders, I rolled my motorcycle into the Kennedy Space Center in Florida, after a long ride from Toronto, to watch the launch of a new spacecraft called Voyager. (It was actually Voyager 2 that launched that day; due to delays, Voyager 1 launched two weeks later).

It didn't gather much attention back then - there were no crowds lining beaches along the way, as there were for the shuttle launches. In fact, the viewing stand held a remarkably small group of people.

But, what a group! We were not only the last people to ever see the spacecraft before it headed out to the stars, but this group had attached a message for the next set of eyes to see it, eyes which would be on alien heads.

1977 was a special time in planetary science because nature provided a rare opportunity to do a "grand tour" of the outer Solar System, thanks to a grand conjunction of the four largest planets. Jupiter, Saturn, Uranus and Neptune all lined up on the same side of the Sun.

The twin Voyager probes took advantage of that alignment to use the gravity of one planet to slingshot themselves to the next, thereby saving tremendous amounts of fuel and time. In fact, the spacecraft were actually accelerated by those gravitational boosts as they went along, gaining enough momentum to leave the Solar System altogether. Only their two predecessors, Pioneer 10 and 11, had performed the same escape maneuver.

As the countdown reached zero, a white hot flame appeared, so brilliant it looked as though a piece of the Sun had been attached to the bottom of the rocket and was lifting it into the sky. It rose smoothly, then began accelerating faster and faster, clawing its way off the planet. There was no slow, majestic rising up like the huge moon rockets or space shuttles - this was a missile, and it was out of sight through the high clouds in less than 15 seconds. By six o'clock that evening, it was beyond the orbit of the Moon.

On the grass in front of the viewing stand, Carl Sagan, famous astronomer of the time, turned back with tears in his eyes and said, "We sent a spaceship to the stars!"

The other members of the group smiled thoughtfully because their message was on its way.

Sagan had convinced NASA that the four human-made objects destined to leave our Solar System should carry symbols of some kind, to tell any aliens who might find one of them where it came from and who built it - a sort of greeting card from planet Earth.

He managed to get simple engraved plaques on the two Pioneer spacecraft. But for Voyager, he gathered together a small team, including Dr. Frank Drake (one of the founders of the SETI - Search for Extra Terrestrial Intelligence - Institute, who sent the first signal to space intended for aliens, using the world's largest radio telescope), as well as space artist Jon Lomberg and other scientists. Together, they produced two gold records called "Sounds of Earth" that were bolted to the sides of the Voyager spacecraft.

The records contain about an hour-and-a-half of music that spans the ages, sound effects of human activities, and people saying hello in 55 different languages. The cover of the record has an illustration, with instructions on how to play it and the location of the Earth in the galaxy, all in binary code.

There is a very slim chance the Voyagers will be spotted as UFOs by aliens, and much doubt as to whether they would be able to understand the messages, but at least they were sent.

It took 12 years for the Voyagers to complete their grand tour of the giant planets. Over that time, I made regular pilgrimages to the Jet Propulsion Laboratory in Pasadena, Calif., to watch pictures come down from alien worlds.

To our delight and surprise, the real stars of the show were the moons. They came in different colours, one with volcanoes, others covered in ice, one with an atmosphere thicker than Earth's, and Voyager discovered many, many more moons we didn't even know existed.

The Voyager project became a journey of pure discovery, not unlike the voyages of Magellan, Cook or Vancouver, who set out over the horizon to chart new territories. As a journalist witnessing this incredible odyssey, it was like being on board one of those ships every time the lookout shouted, "Land Ho!"

But Voyager was also a demonstration of just how primitive and slow our space-faring technology is. During the time it took Voyager to cross our Solar System once, my hair rose up from my shoulders and began showing streaks of grey. The typewriter I used to report on the launch became a computer by the time we reached Neptune, a computer that was more powerful than the one on Voyager itself. The scientists also turned grey, bald, and some died along the way.

We are a long, long way from the star-hopping warp drive depicted in Star Trek.

35 years later, the 20-watt transmitters on the two aging spacecraft are still sending back signals that now take 16 hours to reach Earth. They are more than 100 times farther from the Sun than we are, and about to reach interstellar space, where they will become the first to report back about conditions between the stars, a region we have never explored before.

The rugged probes could keep running until or even beyond 2020, but eventually the power will run down, fuel will be depleted and the Voyagers will become silent travelers forgotten in time. Covering a billion-and-a-half kilometres every three years, it will take 40,000 years for Voyager 1 to reach another star and almost 300,000 years for Voyager 2 to approach Sirius, the brightest star in our sky.

Even if no one out there spots them, the Voyagers will continue to remain intact for at least 500,000 years because there is very little corrosion in interstellar space.

As we walked away from the launch site on that historic day in 1977, all of us in the group were thinking about the fact that this little piece of humanity we had just sent across the galaxy would outlive civilization. The face of the Earth will change as continents shift, Ice Ages will come and go, and who knows what kind of life will have evolved on this planet.

But out there those little probes, carrying their messages to anyone who might find them, will journey on.

35 years in space? That's nothing.