NASA’s Voyager 2 probe lifted off on August 20, 1977, quickly followed by its twin, Voyager 1, on September 5.
Launched in 1977, both probes traveled to Jupiter and Saturn, with Voyager 1 moving faster and reaching them first.
Together, the probes unveiled much about the Solar System’s two largest planets and their moons.
Voyager 2 also became the first and only spacecraft to fly close to Uranus (in 1986) and Neptune (in 1989), offering humanity remarkable views of these distant worlds.
While Voyager 2 was conducting these flybys, Voyager 1 headed toward the boundary of the heliosphere.
Upon exiting it in 2012, Voyager 1 discovered that the heliosphere blocks 70% of cosmic rays.
Voyager 2, after completing its planetary explorations, continued to the heliosphere boundary, exiting in 2018.
The twin spacecraft’s combined data from this region has challenged previous theories about the exact shape of the heliosphere.
“Today, as both Voyagers explore interstellar space, they are providing humanity with observations of uncharted territory,” said Voyager’s deputy project scientist Dr. Linda Spilker, a researcher at NASA’s Jet Propulsion Laboratory.
“This is the first time we’ve been able to directly study how a star, our Sun, interacts with the particles and magnetic fields outside our heliosphere, helping scientists understand the local neighborhood between the stars, upending some of the theories about this region, and providing key information for future missions.”
“The heliophysics mission fleet provides invaluable insights into our Sun, from understanding the corona or the outermost part of the Sun’s atmosphere, to examining the Sun’s impacts throughout the Solar System, including here on Earth, in our atmosphere, and on into interstellar space,” said Dr. Nicola Fox, director of the Heliophysics Division at NASA Headquarters.
“Over the last 45 years, the Voyager missions have been integral in providing this knowledge and have helped change our understanding of the Sun and its influence in ways no other spacecraft can.”
Over the years, the Voyager team has grown accustomed to surmounting challenges that come with operating such mature spacecraft, sometimes calling upon retired colleagues for their expertise or digging through documents written decades ago.
Each Voyager is powered by a radioisotope thermoelectric generator containing plutonium, which gives off heat that is converted to electricity. As the plutonium decays, the heat output decreases and the Voyagers lose electricity.
To compensate, the researchers turned off all nonessential systems and some once considered essential, including heaters that protect the still-operating instruments from the frigid temperatures of space.
All five of the instruments that have had their heaters turned off since 2019 are still working, despite being well below the lowest temperatures they were ever tested at.
Recently, Voyager 1 began experiencing an issue that caused status information about one of its onboard systems to become garbled.
Despite this, the system and spacecraft otherwise continue to operate normally, suggesting the problem is with the production of the status data, not the system itself.
The probe is still sending back science observations while the engineering team tries to fix the problem or find a way to work around it.
“The Voyagers have continued to make amazing discoveries, inspiring a new generation of scientists and engineers,” said Voyager’s project manager Suzanne Dodd, a researcher at NASA’s Jet Propulsion Laboratory.
“We don’t know how long the mission will continue, but we can be sure that the spacecraft will provide even more scientific surprises as they travel farther away from the Earth.”Sci News
An amazing achievement of human ingenuity and engineering design! Currently, Voyager 1 and Voyager 2 are about 14.6 billion miles and 12.1 billion miles from Earth, respectively. Times-of-flight for radio signals to reach Earth from the probes are about 22 hours and 18 hours, respectively. At their current speeds in their journeys away from the sun (38,000 mph and 34,400 mph) it would still take nearly 17,700 years for Voyager 1 to travel 1 light year. Since the Sun’s nearest stellar neighbor is about 4.2 lyrs away, interstellar space travel for humans remains heavily on the fictional side of science fiction.