Voyager 1: 10 Rare Facts About Its Interstellar Journey

Voyager 1 is the farthest human-made object from Earth, traveling beyond the Solar System into interstellar space. Launched by NASA on September 5, 1977, its primary mission was to explore Jupiter and Saturn. However, more than 47 years later, it continues to send valuable data from a region where no spacecraft has gone before.

While many know about its Golden Record and the famous Pale Blue Dot image, Voyager 1 has a history filled with rare and surprising facts that make its journey even more fascinating.

Voyager 1: 10 Amazing Facts About Its Interstellar Journey

With every passing second, Voyager 1 gets farther away from us. In the coming years, we can't even be sure NASA will be able to communicate with it. Voyager 1 has already far outlived its expected mission lifespan and may continue to travel through space for billions of years (at least). While Voyager 1 continues its endless journey, let's learn about some of its rare and exclusive facts that you might never have heard. Check the facts below and take your time to read them.

Image Credit: NASA/JPL-Caltech

1. Voyager 1 Was Always Meant to Take the Lead

Although NASA launched Voyager 2 first, on August 20, 1977, Voyager 1’s faster trajectory was specifically designed to reach Jupiter and Saturn before its twin. Thanks to a stronger gravity assist from Saturn, Voyager 1 quickly overtook Voyager 2 and ultimately became the first spacecraft to reach interstellar space.

2. It Survived a Deadly Radiation Encounter at Jupiter

During its flyby of Jupiter in 1979, Voyager 1 passed through the planet’s intense radiation belts. The radiation was so extreme that it briefly glitched some of the spacecraft’s instruments. NASA engineers feared it could permanently damage the probe, but Voyager 1 recovered and continued its mission, providing groundbreaking images of Jupiter and its moons.

3. Voyager 1's Data Takes Over 22 Hours to Reach Earth

As of early 2025, Voyager 1 is over 15 billion miles (24 billion km) from Earth. Because of this vast distance, radio signals traveling at the speed of light take 22.5 hours to reach the spacecraft—and another 22.5 hours for a response.

Every command NASA sends must be carefully planned, as even the simplest message takes nearly two full days to get a reply.

4. Voyager 1 Uses a 1970s Tape Recorder for Data Storage

Voyager 1’s onboard computer system has only 69.63 KB of memory, far less than a modern calculator. Instead of a digital hard drive, it uses a tape recorder to store scientific data before transmitting it to Earth.

This old technology has remarkably outlasted modern storage devices, proving that NASA’s engineering was decades ahead of its time.

5. The Golden Record May Never Be Found

Voyager 1 carries the Golden Record, a time capsule with Earth’s sounds, images, and music. However, there’s a high chance that no one will ever find it.

Source: NASA Website

The spacecraft is not targeted toward a specific star. It will take 40,000 years before it even comes close to another star (Gliese 445). The record will last for over a billion years, but the odds of an alien civilization discovering and decoding it are extremely low.

6. Voyager 1 is in "Uncharted Territory" — And NASA Struggles to Keep It Alive

Voyager 1 crossed into interstellar space on August 25, 2012, but scientists were surprised by what they found. Instead of a clean boundary, the heliopause (where the Sun’s influence ends) turned out to be a complex and dynamic region.

As the spacecraft moves deeper into interstellar space, its systems are aging and malfunctioning. In 2021, it began sending back corrupted orientation data, forcing NASA engineers to find a remote fix—something never done before at such a distance.

7. Voyager 1 Will Eventually Go Completely Silent

Voyager 1 runs on plutonium-238, housed in a Radioisotope Thermoelectric Generator (RTG) that has been slowly decaying for decades. In its early years, it generated 470 watts of power, but now it has less than 250 watts.

NASA has already shut down non-essential systems to conserve energy. By 2030, the spacecraft may no longer have enough power to communicate. Even after it stops transmitting, it will continue drifting through space forever.

8. It Wasn’t Originally Designed to Leave the Solar System

Image Credit: ESA (European Space Agency)

Voyager 1’s primary mission was to study Jupiter and Saturn. While mission planners knew it had the potential to escape the Solar System, that wasn’t its main goal. However, thanks to precise trajectory planning, it had enough speed to break free of the Sun’s gravity.

This unexpected journey has made Voyager 1 one of the most significant space missions in history.

9. Voyager 1 Will Travel for Billions of Years

Even when Voyager 1 loses power, it will continue moving through space indefinitely. It’s currently traveling at 38,000 miles per hour (61,000 km/h), meaning it won’t slow down anytime soon.

By the time it reaches another star system, human civilization may no longer exist, but Voyager 1 will still be drifting through the cosmos—a silent messenger from Earth.

10. It’s One of the Greatest Space Missions Ever

Voyager 1 has gone farther than any spacecraft before it. Despite being built with 1970s technology, it still provides scientific data that no other probe can match.

Even after it stops communicating, it will remain a symbol of humanity’s curiosity and desire to explore the unknown.

Frequently Asked Questions About Voyager 1

Q. Where is Voyager 1 at now?

Voyager 1 is currently in interstellar space, far beyond the heliopause, the boundary of the Sun's influence. It's the most distant human-made object from Earth, traveling through the vast emptiness between stars.  As of late 2023, it's over 15 billion miles from the Sun.

Q. Has Voyager 1 left the Milky Way?

No, Voyager 1 has not left the Milky Way galaxy. It's traveling through interstellar space within the galaxy. The Milky Way is a vast collection of billions of stars, and Voyager 1 is still within its boundaries, although far from our solar system. It will take many thousands of years for it to leave the galaxy.

Q. Can Voyager 1 still take pictures?

Voyager 1's cameras were turned off after it completed its primary mission of exploring Jupiter and Saturn.  This was done to conserve power, as the spacecraft's power source is dwindling.  It is no longer capable of taking and transmitting images.

Q. What planet is Voyager 1 closest to?

Voyager 1 is not particularly close to any planet at this point. It's far beyond the outer planets of our solar system and is traveling through interstellar space.  It's much closer to interstellar space than any planet.

Q. How does Voyager travel without fuel?

Voyager 1 didn't use fuel for its long journey.  A rocket launch provided the initial push.  Then, it used "gravity assists" from Jupiter and Saturn, like cosmic slingshots, to gain speed and change direction.  Now, it cruises through space thanks to inertia – the tendency of a moving object to stay moving.  Small thrusters help it keep its antenna pointed at Earth, but it doesn't have brakes or a way to significantly change course.

Q. Will Voyager 1 ever hit anything?

The chances of Voyager 1 colliding with anything significant are extremely low. Interstellar space is incredibly vast and mostly empty. While there are tiny particles and dust grains, the probability of a collision with something large is negligible.

Q. How does NASA control Voyager 1?

NASA communicates with Voyager 1 using radio signals.  Commands are sent from Earth, and the spacecraft transmits data back.  Due to the immense distance, it takes many hours for signals to travel to and from the spacecraft.  This requires careful planning and precise timing.

Conclusion

Voyager 1, a true trailblazer, pushes the boundaries of human exploration, venturing further into the vast unknown of interstellar space than anything we've ever built. It's a powerful symbol of our insatiable curiosity and our relentless drive to discover what lies beyond. Even as its signal weakens and eventually falls silent, Voyager 1's legacy as a pioneer of space exploration will endure, a testament to humanity's enduring quest to understand our place in the universe.