NASA begins shutting down legendary Voyager space probes launched 45 years ago
The Voyager probes were launched into space almost 45 years ago, one of them visited Jupiter and Saturn, while the other, in addition to passing by those two planets, also reached Uranus and Neptune. They have become the first spacecraft to enter interstellar space, and thus the first objects created on Earth to travel so far. But this exciting adventure, which has given us so many discoveries, is nearing its end.
These spacecraft are powered by a radioisotope thermoelectric generator (RTG), which, roughly speaking, obtains energy from the natural decay of radioactive material. However, this aging system loses about 4 watts per year of power, which has forced NASA to gradually shut down the instruments.
Engineers at the U.S. space agency have already shut down some scientific measurement equipment in the past to optimize power consumption. In 2019 they switched off the Cosmic Ray Subsystem (CRS) heater on Voyager 2, a resource that protected this part of the spacecraft from the very low temperatures of space. Surprisingly, the instrument demonstrated unique resilience and continued to function, despite dropping to a chilly -59 degrees Celsius.
These types of changes, and any others that require sending commands, such as when it was necessary to activate Voyager 1’s thrusters after 37 years of inactivity, are extremely complex due to the distance at which the spacecraft are located. Sending messages between Earth and Voyager 1 takes almost 22 hours and about 18 hours for Voyager 2, communications that are managed through the antennas that make up NASA’s Deep Space Network.
Thus, through this communications link, the U.S. agency will try to optimize the energy consumption of the legendary probes so that they can remain operational until around 2030. At the moment, Voyager 2 has five instruments in operation, and Voyager 1 has four, but they will be progressively shut down, one of the last to stop working being the magnetometer to determine whether each of the outer planets had a magnetic field.
For the time being, no exact date has been revealed when the probes will stop working, but as mentioned above, if all goes well, they could continue their mission for several more years. And when the time comes to say goodbye, we will no longer be able to communicate with them, but these spacecraft will continue to travel the far reaches of space and carry with them the golden discs with sounds from Earth, greetings in several languages, images, music, and even a message from then US President Jimmy Carter.