IOWA CITY, Iowa — Nearly 47 years ago, two NASA spacecraft were headed on one of the greatest journeys across our solar system to fly past and discover our outer gas giants.

They were launched in a special planetary window, which only occurs once every 176 years. It allows these spacecraft to use the gravitational pull of each planet they fly past to change their trajectory, allowing them to arrive at the next planet in their path with minimal fuel consumption.

The Voyager spacecraft paved the way for our understanding of our solar system, but it is now more than 25 billion miles from Earth. It takes about 23 hours for light and radio signals to reach it one way, and it continues to change our understanding of the cosmos.

The instruments still on board and operational were built and are still operated by the Department of Physics and Astronomy at the University of Iowa.

One of these is the Plasma Wave subsystem, which measures subtle waves in plasma fields around planets and in space.

The instrument has played a central role in some of our most incredible discoveries in space, including the dataset confirming when Voyager entered the interstellar medium beyond our solar system in 2012.

This also played a role indetect lightning on another planet for the first time in the early 1980s. Lightning sends out a wide range of electromagnetic waves. Due to the different speeds at which each of these waves travel, it creates a strange descending whistling sound.

This noise was picked up by the University of Iowa instrument on the traveler as it flew overhead, using the technique that first discovered the telltale sound of lightning when spies attempted to listen to their enemies at the start of World War II. .

The methodology shows how research over decades can continue to build on top of each other, leading to greater discoveries over the years.

Dr. Bill Kurth, a research scientist at the University of Iowa and co-investigator of the Voyager Plasma Wave, participated in the initial development of the instrument nearly half a century ago and continues to monitor the returned data by the aging spacecraft. to this day.

While I was a graduate student, I worked on hardware that would fly with the Voyager spacecraft. I defended my doctoral dissertation literally a month before Voyager 1 arrived at Jupiter, and then asked if I could stay longer to see what kind of data we would get. I didn’t realize I would still be doing this 45 years later,” Dr. Kurth said.

It’s really exciting, I think, every time I look at a new data file I realize that I’m seeing something that no one has ever seen before.

As spacecraft age, instruments are shut down to save energy and extend the life of the spacecraft. Of the ten or so instruments on board, only four remain. The University of Iowa’s instrument, which helps us better understand our place in the stars, is one of them still in operation.

It’s still unclear how much time the Voyager probes have left, but predictions show they could arrive as late as the early 2030s. However, they will still drift through the vastness of space, likely outliving our time. own star, the sun, long after they have stopped.

You and will find more information on the The University of Iowa’s involvement in Voyager missions here or their involvement in a multitude of NASA flagship missions here.

To follow Voyager or learn more about it, check out the links below on NASA’s mission pages.