Voyager 2 is a space probe launched by NASA on August 20th, 1977, to study outer planets. Part of the Voyager program, the probe was launched 16 days before its twin, Voyager 1, on a trajectory that took longer to reach Jupiter and Saturn but allowed subsequent meetings with Uranus and Neptune.
Its primary mission ended with the exploration of the Neptunian system on October 2, 1989, after visiting the Uranian system in 1986, the Saturnian system in 1981, and the Jupiterian system in 1979. Voyager 2 is now in its extended mission to study the edge of the solar system and functions as 42 years, four months, and 20 days. He is still in contact with NASA.
Shortly after launch, the flight control computer incorrectly diagnosed a steering problem and initiated maneuvers that led to a 2-hour radio link with Terra. The built-in calculation solved autonomously the problem that arose with the introduction of the wrong parameters in the steering control system.
NASA Regained Control Over The Voyager-2 Space Probe
A few weeks later, the ground control team, seized by new projects, failed to send a radio message to the probe. The absence of receiving a message was interpreted by the probe as a malfunction of the primary radio receiver and passed to the backup receiver.
Afterward, the safety of the leading receiver’s power supply jumped off, permanently removing it from the operation. The backup receiver was functional, but a broken capacitor meant that only transmissions sent at a precise frequency could be received. That frequency would be affected by the rotation of the Earth (due to the Doppler effect) and the temperature of the receiver onboard, among other things.
For each subsequent transmission to Voyager 2, the engineers needed to calculate the specific frequency of the signal to be received by the spacecraft. It’s impressive that using the probe, such old technology continues to operate.