Voyager II launched before Voyager I, leaving the launch pad in August of 1977. Voyager I launched in September of 1977 on a mission to explore the outer planets with its twin. Both are in different trajectories and both with slightly different missions.
After 20 years, both probes are well into Interstellar space beyond the Solar System. Both of them are working. Some of the hardware on them has stopped functioning, some of it because of the cold of space, some because of the radiation, and when these parts breakdown, the engineering team has to figure out how to fix them, or work around them. Once and oscillator stopped functioning and an automatic reset, set four decades ago, reset operating system. They were able to figure out how to send and received signals and commands on analog electrical equipment that isn’t even made anymore.
They are so far out it takes about 17 hours and 20 minutes for signals to traverse the space between us at the speed of light. The NYT points out that the on board computers have 235,000 times less memory and 175,000 times less speed than a 16 gigabyte cellphone. They discovered many of the 48 moons orbiting Saturn and Jupiter. They flew threw Jupiter’s rings and studied the atmosphere of the gas giants. They sent us back valuable and stunning data on Uranus and Nepture.
They are travelling at about 38,000 miles an hour and are both still functioning.
These engineers are still at work watching the two oldest eyes on the solar system
Enrique Medina; Control System Engineer with the team since 1986. Suzanne Dodd;Voyager’s flight-team project manager. Jefferson Hall; He began working with the Voyager team in 1978 as the mission flight director. Sun Kang Matsumoto;
Joined the Voyager team in 1985. Larry Zottarelli; who recently retired from the Voyager flight crew was there from the launch.Roger Ludwig; flight engineer, joined in 1978. Tom Weeks: Hardware Engineer, he started with Voyager in 1983