What human made object has traveled farther from Earth than any other?

15,780,000,000 Miles Away From Earth

Of all the things humanity has built, one object has traveled farther than any other. It is a testament to human ingenuity, curiosity, and the remarkable foresight of its creators. That object is a 1,592-pound (722-kilogram) robotic probe named Voyager 1.

As of late 2025, Voyager 1 is more than 15.78 billion miles (25.39 billion kilometers) from Earth. This distance is so vast that it is difficult to comprehend. It is approximately 169.8 times the distance from the Earth to the Sun. This probe, launched in 1977, has left our solar system’s planets far behind and is now journeying through the cold, empty expanse between the stars.

Voyager 1 is not alone in its exodus. It is the leader of a small fleet of five spacecraft, built by NASA, that are on trajectories to leave our Solar System forever. Its twin, Voyager 2, follows behind it as the second-farthest object. Farther back are Pioneer 10 and Pioneer 11, pioneers from an earlier era, now silent. The fifth is New Horizons, the modern explorer of Pluto and the Kuiper Belt. But Voyager 1 is, and will remain, the front-runner.

This article explores the journey of Voyager 1: how it got to where it is, what it discovered, how we still communicate with it across an unfathomable gulf, and the message it carries on behalf of all humanity.

A Spacecraft Named Voyager

Voyager 1 is a robotic space probe. It and its twin, Voyager 2, were designed and built by NASA’s Jet Propulsion Laboratory (JPL). Their original mission was to study the outer planets, Jupiter and Saturn. They were launched in 1977, a time when desktop computers did not exist and our understanding of the outer solar system was based on blurry images from Earth-based telescopes.

The spacecraft itself is a marvel of 1970s engineering. Its “brain” is a computer with about 240,000 times less memory than a typical smartphone. Its data is stored not on hard drives but on an 8-track digital tape recorder. It is powered not by solar panels, which would be useless in the dark outer reaches, but by Radioisotope Thermoelectric Generators (RTGs). These devices convert heat from the natural decay of plutonium-238 into electricity. This power source, though slowly diminishing, is what has allowed the probe to operate for nearly five decades.

Today, Voyager 1 is no longer exploring planets. It has entered a new region of space, a new environment that no other human object has ever sampled. It is in interstellar space, the vast emptiness that separates the stars. It continues to travel at an astonishing speed of over 38,000 miles per hour (about 17 kilometers per second) relative to the Sun. At this speed, it covers approximately 3.6 Astronomical Unit (AU)s every year.

The Grand Tour

The Voyager missions were made possible by a rare cosmic alignment. Once every 176 years, the four giant outer planets – Jupiter, Saturn, Uranus, and Neptune – line up on the same side of the Sun. This alignment allowed mission planners to design a “Grand Tour,” using a technique called a gravity assist.

A gravity assist, or “slingshot,” is a maneuver that uses a planet’s gravity to change a spacecraft’s speed and direction without using fuel. As the spacecraft approaches a planet, the planet’s gravity pulls it in, accelerating it. The spacecraft then swings around the planet and flies off in a new direction. By carefully timing the approach, engineers can “steal” a tiny amount of the planet’s orbital energy. The planet is slowed in its orbit by an infinitesimal amount, and the spacecraft is sped up by a very large amount.

This technique was the key to the Voyager missions. It allowed them to reach the outer solar system in a matter of years rather than decades. Voyager 1 would use Jupiter’s massive gravity to bend its path and fling it toward Saturn. This maneuver saved years of travel time and gave the probe the immense speed it needed for its journey.

Voyager 1’s Planetary Encounter

While Voyager 2 was launched first (on August 20, 1977), Voyager 1 was put on a faster, more direct path. It launched on September 5, 1977, and overtook its twin.

The Jovian System

In March 1979, Voyager 1 arrived at Jupiter. The images and data it sent back were revolutionary. It provided the first detailed, close-up look at the Great Red Spot, a storm three times the size of Earth. It discovered Jupiter’s faint, dusty rings, which were invisible from Earth.

The mission’s most stunning discovery came from an unexpected place: Jupiter’s small, pizza-colored moon, Io. A JPL navigation engineer, Linda Morabito, was analyzing a long-exposure image of Io when she spotted what looked like a plume erupting from its surface. It was a volcano. Not a dead, ancient volcano, but a live, active one, spewing sulfur and ash hundreds of miles into space. Until that moment, Earth was the only body in the solar system known to have active volcanoes. Voyager 1’s discovery showed that other worlds could be geologically alive, and it transformed planetary science overnight.

The Saturn Encounter

After its Jupiter flyby, the gravity assist sent Voyager 1 hurtling toward Saturn, which it reached in November 1980. Once again, it rewrote the textbooks. Images showed that Saturn’s rings, which appear solid from Earth, were actually composed of thousands of individual ringlets. It discovered strange “braided” patterns in the F-ring, guided by two small “shepherd” moons.

Here, the mission team faced a choice. Voyager 1’s path could be bent to take it to Uranus and Neptune, completing the Grand Tour. Or, it could be diverted to make a very close flyby of Saturn’s largest moon, Titan. Titan was a tantalizing target. It was the only moon in the solar system known to have a thick, hazy atmosphere. Scientists were eager to see if this atmosphere contained the building blocks of life, perhaps resembling a frozen, primordial Earth.

The team chose Titan. The close pass in 1980 revealed a dense, smoggy atmosphere of nitrogen and methane, but its surface remained hidden. This flyby was a fateful one. The strong gravitational pull of Titan bent Voyager 1’s trajectory, flinging it “up” and out of the ecliptic plane – the flat plane where most of the planets orbit. This maneuver ended its planetary encounters forever and set it on its final course: a path out of the solar system.

The Sister Ship’s Journey

While Voyager 1 headed for the exit, its twin, Voyager 2, was able to complete the full Grand Tour. Because it did not make the close pass of Titan, its trajectory remained on the ecliptic plane, allowing it to use Saturn’s gravity to aim for the next planet.

Voyager 2 flew past Uranus in 1986, becoming the first and only spacecraft to ever visit the ice giant. It discovered new moons, new rings, and a bizarre magnetic field, tilted on its side just like the planet. In 1989, it reached Neptune, again the first and only visitor. It discovered the Great Dark Spot, a storm similar to Jupiter’s, and active geysers erupting from the surface of the icy moon Triton.

After its Neptune encounter, Voyager 2 was also flung out of the solar system, but in a different direction and at a slower speed than its sibling. It remains the second-farthest human-made object, a silent companion to its trailblazing twin.

Breaching the Solar Bubble

For decades after its Saturn flyby, Voyager 1 coasted through the dark. Its mission changed from one of frantic planetary encounters to a new, long-term scientific endeavor: The Voyager Interstellar Mission. Its goal was to find the “edge” of the solar system.

This edge isn’t a hard line. The Sun emits a constant, high-speed stream of charged particles called the solar wind. This solar wind travels out in all directions, creating a vast magnetic “bubble” around the solar system known as the heliosphere. This bubble is our system’s protective shield, deflecting many of the high-energy cosmic rays that originate from distant supernovae.

Finding the Boundary

Scientists hypothesized that this bubble had three main boundaries, and Voyager 1 was their instrument to find them.

The first boundary is the Termination Shock. This is the point where the solar wind, expanding at supersonic speeds, abruptly slows down as it begins to feel the pressure of the interstellar medium (the gas and dust between the stars). In December 2004, after 27 years of travel, Voyager 1’s instruments detected this shockwave. It had entered the “buffer zone” of the outer solar system.

The second region is the Heliosheath. This is the turbulent, messy area beyond the termination shock where the slowed-down solar wind is pushed and shaped by the interstellar medium, like water from a faucet hitting a sink. Voyager 1 spent nearly eight years traveling through this region.

The final boundary is the Heliopause. This is the true “edge” of the heliosphere, the point where the Sun’s solar wind is finally stopped and the pressure from the interstellar medium dominates. It’s the line between “inside” our solar system’s influence and “outside” in the galaxy.

On August 25, 2012, Voyager 1’s instruments detected a sudden, massive change. The level of solar particles dropped to almost zero, while the level of high-energy galactic cosmic rays jumped dramatically. The data was clear. Voyager 1 had punched through the bubble. It had become the first object created by human hands to enter interstellar space. Its twin, Voyager 2, crossed this same boundary in a different location in November 2018.

The Long-Distance Call

As of late 2025, Voyager 1 is 15.78 billion miles away. How is it possible to communicate with a 48-year-old spacecraft at such a distance? The answer lies in a global network of massive antennas and a lot of patience.

The communication link is maintained by the Deep Space Network (DSN). The DSN consists of three main facilities, spaced roughly 120 degrees apart around the globe: in Goldstone, California; near Madrid, Spain; and in Canberra, Australia. This spacing ensures that as the Earth rotates, one of the stations can always maintain a line of sight to the spacecraft.

The challenge is twofold: distance and power.

Voyager 1’s transmitter has the power of a refrigerator light bulb – about 23 watts. By the time this faint signal travels across the solar system, it is unimaginably weak. The signal that reaches the DSN’s massive 70-meter (230-foot) dishes is a billionth of a billionth of a watt. These incredibly sensitive “ears” are just barely able to pick it out from the background noise of the cosmos.

Then there is the time delay. Radio waves, like all light, travel at the speed of light. At Voyager 1’s current distance, it takes a signal approximately 23.5 hours to travel from Earth to the probe. This means a simple “hello” takes 23.5 hours to arrive. If the probe understands the command and sends back an “OK,” that response takes another 23.5 hours to travel back.

A single round-trip communication with Voyager 1 takes nearly 47 hours. This makes operating the spacecraft an exercise in extreme patience and careful planning.

A Glitch in the Void

This 47-hour time lag was put to the test recently. In November 2023, the mission team at JPL was horrified when Voyager 1’s communications suddenly stopped making sense. The probe was still transmitting a signal, but the data was a meaningless, garbled stream of ones and zeros, like a robotic dial tone.

The problem was in the Flight Data System (FDS), one of the probe’s three onboard computers. The FDS is responsible for collecting science and engineering data and packaging it into a single data stream to be sent to Earth. Something in the FDS had become corrupted.

For months, the engineering team worked to diagnose a problem on a computer system built in the 1970s, from 15 billion miles away, with a 47-hour delay for every single command they tried. They couldn’t just reset it. They had to “poke” the system, send a command, and then wait two full days to see what, if anything, happened.

In March 2024, they had a breakthrough. They sent a special command that prompted the FDS to send a full “memory dump” – a complete readout of its entire software. After waiting two days for the readout to arrive, engineers began to pore over the code. They traced the problem to a single faulty memory chip. A small portion of the F-D-S memory – only about 3% – had been damaged, which was enough to corrupt all the data.

The chip itself couldn’t be fixed. The team had to devise an ingenious workaround. The code that was stored on that one bad chip was essential for the spacecraft’s function. The engineers had to meticulously break that code into smaller pieces and then find new places to store those pieces in other parts of the computer’s memory. It was like taking a single broken shelf in a library and finding space for its books on hundreds of other shelves, all while making sure the library’s card catalog was perfectly updated so the system could still find them.

They sent the first part of this software patch in April 2024. They waited 47 hours. The fix worked. The probe began sending back understandable engineering data. In May and June, they sent further patches, and one by one, the science instruments came back online. After more than six months of silence, Voyager 1 was, unbelievably, back to its job of exploring the interstellar medium.

The Fading Power

Voyager 1’s journey can’t last forever. Its lifeline is the slowly fading heat from its plutonium power source. The Radioisotope Thermoelectric Generators (RTGs) have performed flawlessly, but their power output drops by about 4 watts every year.

To keep the probe alive, engineers have been making difficult choices for decades. To save precious electricity, they have been methodically shutting down systems. The cameras, which took the last of their famous photos in 1990, were turned off long ago. Next went the heaters for many of the instruments. The probe is now operating at temperatures far below its original design limits, a testament to its robust construction.

As of 2025, Voyager 1 has three science instruments still active: the Magnetometer (MAG), the Low-Energy Charged Particles (LECP) instrument, and the Plasma Wave Subsystem (PWS). These are the instruments that are tasting, feeling, and measuring the interstellar medium.

The JPL team will continue to conserve power, likely shutting down instruments one by one over the next few years. The end is predicted to come sometime around 2030, or perhaps as late as 2036. At some point, there will not be enough electricity left to run even a single science instrument and the transmitter. The signal will go flat, and Voyager 1 will fall silent forever.

But it will not stop.

A Message in a Bottle

Long after its power fades and its long-distance conversation with Earth ceases, Voyager 1 will continue its journey, coasting silently through the Milky Way galaxy. Its creators knew this would be its fate, and they prepared one final, remarkable piece of the mission.

Affixed to the side of both Voyager 1 and 2 is a 12-inch, gold-plated copper phonograph record. It’s the Voyager Golden Record, a time capsule from Earth intended for any intelligent extraterrestrial civilization that might one day find the derelict probe.

The contents of the record were selected by a committee chaired by the astronomer Carl Sagan. It’s a portrait of humanity, containing:

• 115 Images: These include diagrams of our science and mathematics, pictures of our solar system, images of landscapes, animals, and scenes of human life from around the world.
• Sounds of Earth: The record includes the sounds of wind, rain, and surf; animal sounds like birdsong and whale calls; and the sounds of human activity, like a train, a kiss, and a mother’s first words to a newborn.
• Greetings: It carries spoken greetings in 55 different languages, from ancient Akkadian to modern English (“Hello from the children of planet Earth”).
• Music: The musical selection is eclectic, designed to showcase the breadth of human culture. It includes works by Johann Sebastian Bach and Ludwig_van_Beethoven, a Navaho night chant, and Chuck Berry’s rock-and-roll classic “Johnny B. Goode.”

The record’s cover is a message in itself. It includes diagrams that show, in scientific language, how to play the record. Most famously, it includes a map – a diagram of 14 pulsars (rapidly spinning stars) that can be used to triangulate the record’s origin: our Sun. It’s a map that says, “This is where we are from.”

The Golden Record is a message of peace and a gesture of cosmic optimism. It is unlikely to ever be found. The space between stars is too vast. But it will survive, along with its sister record on Voyager 2, long after the Sun has died and the Earth is gone. It may be the last surviving artifact of our civilization.

The Other Pathfinders

While Voyager 1 is the most distant, four other spacecraft are also on escape trajectories.

Pioneer 10, launched in 1972, was the true trailblazer. It was the first probe to cross the asteroid belt and the first to fly by Jupiter. It is now the third-farthest object, but its power source is dead. NASA’s last, very faint signal from it was received in 2003. It also carries a small plaque, the Pioneer plaque, a simpler precursor to the Golden Record.

Pioneer 11, launched in 1973, was the first to visit Saturn. It is the fourth-farthest object and has been silent since 1995.

The fifth and final object is New Horizons. Launched in 2006, it is the “newest” of the interstellar-bound probes. It flew by Pluto in 2015, providing the first clear images of the dwarf planet, and later visited the distant Kuiper Belt object Arrokoth in 2019. It is the fastest probe ever launched from Earth, but because it didn’t get the same massive gravity assists as the Voyagers, it will never catch them.

This table provides a summary of the five interstellar-bound spacecraft.

The Pale Blue Dot

In 1990, long after its encounter with Saturn, Voyager 1 was about 3.7 billion miles from home. At the persistent request of Carl Sagan, NASA mission planners gave the probe one final command before its cameras were powered down for good. They turned it around to look back at the home it had left.

From that great distance, Voyager 1 took a “family portrait” of the solar system, capturing images of six of the planets. In the image containing Earth, our entire world appeared as a single, tiny point of light, a pixel 0.12 in size, caught in a scattered ray of sunlight.

This image, known as the Pale Blue Dot, is one of the most poignant photographs ever taken. It’s a humbling perspective on our place in the universe. It shows our world as a fragile, lonely speck, a tiny stage in a vast cosmic arena.

The Silent Voyage

After its power finally fails in the coming decade, Voyager 1’s scientific mission will be over. Its journey will have just begun.

It will coast through the Oort Cloud, a theoretical shell of icy comets at the very edge of the Sun’s gravitational pull, a process that will take thousands of years. It is heading in the general direction of the constellation Ophiuchus. In about 40,000 years, it will drift within 1.6 light-years of a star named Gliese 445. It isn’t going tothe star, just passing by.

Its voyage will continue for millions and billions of years, orbiting the center of the Milky Way galaxy just as the stars do. It will outlive its creators and the planet they came from. It is a ghost ship, a silent emissary, carrying a golden postcard from a world that will be long gone, a testament to the fact that for a brief moment in time, a curious species on a small blue planet dared to reach for the stars.

Summary

The farthest human-made object is the Voyager 1 probe. As of late 2025, it is over 15.7 billion miles (25.3 billion kilometers) from Earth, a distance that takes radio signals 23.5 hours to cross one way. Launched in 1977, its original mission was to explore Jupiter and Saturn. It revolutionized our understanding of the outer solar system, discovering active volcanoes on Io and the complex, ringed system of Saturn.

A maneuver past the moon Titan sent it on a path out of the solar system. In 2012, it became the first human-made object to enter interstellar space, a region it continues to measure with its remaining active instruments.

Despite its 1970s technology and waning power supply, engineers at JPL maintain communication with the probe via the Deep Space Network (DSN), even overcoming a major communication glitch in 2024. The mission is expected to go silent in the coming years as its power source fails.

Voyager 1 will continue its journey long after it stops transmitting. It carries the Voyager Golden Record, a time capsule of Earth’s sights and sounds, as a silent ambassador to the cosmos. It stands as the pinnacle of human exploration, a small, resilient piece of technology that has crossed the boundary of our solar system and entered the galactic ocean.