Why Voyager 2’s discoveries from interstellar space have scientists excited

Voyager 2, first launched in 1977, is the second human-made machine to have officially entered interstellar space. Her companion spacecraft, Voyager 1, accomplished the feat in 2013. The data being returned by both spacecraft – having passed beyond the heliosphere, past where solar winds still blow plasma outward from the sun – have scientists excited.

As soon as Voyager 2 left the farthest reaches of the solar wind, the density of plasma actually jumped, according to Phys.org. “The marked increase in plasma density is evidence of Voyager 2 journeying from the hot, lower-density plasma characteristic of the solar wind to the cool, higher-density plasma of interstellar space. It’s also similar to the plasma density jump experienced by Voyager 1 when it crossed into interstellar space.”

The information from the boundary between the solar wind and interstellar space is just the latest that the two Voyager spacecraft have imparted. Voyagers 1 and 2 launched in 1977 within 16 days of one another on a mission to explore the outer planets. Voyager 1 flew past Jupiter and Saturn before heading to the outer boundaries of the solar system. Voyager 2 explored Jupiter, Saturn, Uranus and Neptune before soaring beyond.

To give an idea of the length of the twin Voyager 1 and 2 missions, in 1977, Jimmy Carter was president of the United States. Watergate and Vietnam were recent, hurtful memories, and the Cold War was still raging. Donald Trump, the current president of the United States, would start making a name for himself in the New York real estate world the following year when he began to renovate the Commodore Hotel. The current administrator of NASA, Jim Bridenstine, was just two years old.

A lot of history has happened since the Voyager spacecraft first lifted off the launch pad. The Soviet Empire fell. 9/11 happened, sparking the long wars in the Middle East and Afghanistan. The space shuttle program began and ended, with the International Space Station now a permanent home for human beings in low Earth orbit. The internet has bound the human race in a web of information and communication as never before. Diseases have been conquered. Climate change has become a worry and a political issue, hotly debated by politicians and scientists alike. The world population has swelled to more than seven and a half billion people.

That the Voyager spacecraft are still returning good science from billions of miles away is a testament to the state of the art of space technology in the late 1970s. Scientists estimate, though, that within about five years, Voyager 1 and Voyager 2 will run out of the decaying plutonium that fuels their RTG power generators. Then the two spacecraft will fly forever outward, each bearing a gold audio-visual disk containing greetings from the people of Earth.

Unless the Voyager probes collide with something or are picked up by alien space explorers, they will, in theory, keep flying until the end of the universe.

NASA is already thinking of a true, interstellar probe, according to Space.com. A space probe specifically designed to study interstellar space would be packed with enough instruments and power to study the universe beyond the sun’s heliosphere in detail, far beyond the distance where the useful lives of the Voyager spacecraft come to an end.

Along the way, the interstellar probe will explore the Kuiper belt and answer a number of questions that scientists have, including what happens when solar radiation leaves the solar system and what happens when cosmic background radiation enters. The probe may make discoveries that we cannot yet imagine are out there. If approved, the probe could be flying in about a decade.

When humans might follow is, right now at least, confined to speculation and science fiction. But one day, if human civilization has not destroyed itself in the meantime, true star ships might brave the gulf between the stars, built with technology that can currently be only vaguely imagined.

Scientists speculate that one day we may be able to create something called the Alcubierre Warp Drive, which sounds like something from Star Trek, but has a basis in reality. The warp drive would not so much propel a spacecraft as it would manipulate space itself, compressing it ahead of the spacecraft and stretching it behind, riding a “warp bubble” to achieve faster than light speeds.

The adventures and discoveries our descendants may experience, visiting newly discovered exo-planets, will cause the current space program to pale in comparison.

Mark R. Whittington has published a political study of space exploration entitled “Why is It So Hard to Go Back to the Moon?” as well as “The Moon, Mars and Beyond.” He blogs at Curmudgeons Corner.