What do the years 2153 and 2329 have in common? The planets Jupiter, Saturn, Uranus, and Neptune will be on the same side of the sun, something aerospace engineer Gary Flandro discovered in 1965. It happens once every 176 years, and NASA seized on the opportunity 40 years ago with its launch of two probes, Voyager 1 today, and Voyager 2 last month, to unlock the secrets of the outer solar system.
Eight years old at launch, I was one of the beneficiaries of this great undertaking. In the years that followed, the images sent back from the Voyagers—of Jupiter and Saturn and their icy moons and rings—would cover my bedroom walls and guide my thoughts. The Voyagers would venture out even farther, Voyager 2 passing by Uranus and Neptune and stunning us with close-ups of those distant planets as well. Meanwhile, on the longest journeys ever undertaken, the probes reached the boundaries of interstellar space.
NASA’s Voyager probes filled my dreams with vistas no human or robotic eye has ever seen: close-up views of planetary rings over a cratered landscape of a shepherd moon. And they made me think about where human explorers could go if they tried. At an early age, I felt the urge to contribute to this quest as a scientist. In 1982, my parents fulfilled my wish for a telescope. It may have been their mistake, as from then on, not only were they forced to listen to my excitement over asteroids, comets, and eclipses in the Jupiter system and the rings of Saturn, but they were often cajoled into leaving the comfort of the living room and joining me outside at the telescope—sometimes in the bitter cold of a wintery night.
Voyager 1 and Voyager 2 have collected unprecedented and often surprising data: magnetic fields, cosmic rays, energy levels, plasma the sun sends out, and solar wind. In fact, both probes are still measuring data every year, and NASA is in contact with them every day. Most scientists invite and relish the open debate of competing interpretations in the pursuit of understanding, as it is this culture of open debate of ideas that spurs progress for humanity.
For me, the impact of Voyager was intensely personal. Growing up not far from the iron curtain, space exploration seemed to have a rare unifying effect on the two cold-war powers, and it offered a common source of inspiration for young people all across the world. But even today, the uniting influence of exploration—in the study of space and in other science and engineering disciplines—is as urgently needed as ever. Equally important is the power that such undertakings have to inspire in humanity the drive for further exploration—to experience the joy of making new discoveries about our universe and to provide younger generations the curiosity to push beyond our current boundaries.
We can only imagine the thrill that Flandro felt when he discovered the gift that awaited humanity in the year 1977. I am looking forward to shaking his hand—and to shaking hands with the current Voyager team members— on Tuesday, when NASA celebrates the achievements of the Voyager mission on the 40th anniversary of their launch. You may experience first-hand that the joy of finding things out is one of the most rewarding features of a career in science and engineering. Why not consider it?
Arik Posner is a research scientist working in the field of solar, space and planetary physics and currently serves as the Voyager Program Scientist for the NASA/SMD Heliophysics Division in Washington D.C.