A lot can go wrong if you move in interstellar space at a distance of billions of kilometers from the Earth, drawing energy from a single radioisotope thermoelectric generator, and 43 years have passed since the moment when any repairs could be made. This is exactly what happened last week when the Voyager 2 spacecraft automatically went into protected mode due to an unexplained delay in executing commands during the maneuver to calibrate one of the onboard scientific instruments. This delay caused two powerful subsystems to operate at one point in time, the consumption of which exceeded the current capabilities of the power source for the spacecraft.
Finding out the reasons for what happened and finding ways to resolve the situation was a very time-consuming process, given that it takes 17 hours to get the radio signal to cover the distance between Earth and Voyager 2 now. And, after sending the next set of commands to the device, you need to wait about 34 hours in order to find out if this had the desired effect.
Now, NASA experts have managed to incorporate some of the scientific tools of the Voyager 2 apparatus, which have resumed the collection of scientific data. The remaining components and tools of the device are still under consideration, the on-board computer slowly executes self-diagnostic programs downloaded to it, the data from which will help determine when and if these tools can even be turned on again.
The main problem of the Voyager series vehicles launched into space in 1977 is their radioisotope power source, the volume of which is densely filled with small spheres of radioactive plutonium oxide. Initially, this source was capable of generating 470 watts of power. But due to the fact that plutonium has a relatively short half-life (87.7 years), the number of decays of atoms of this element is constantly decreasing and the source of the Voyager 2 apparatus loses power at a speed of 4 watts per year.
In mid-2019, the average power supply of the Voyager 2 was about 280 watts and NASA experts decided to turn off one of the heating elements that maintain the optimum temperature inside the device. Fortunately, the equipment of the device continued to work, despite the decrease in temperature below the point at which it was tested on Earth. Now the Voyager 2 device is transmitting to the Earth the data collected by 5 onboard scientific instruments and, you can say, none of the original team could even count on.
However, the time will come when the power supply of the device will cease to be sufficient even for heating the fuel lines, after which the Voyager 2 will lose the ability to maneuver and will be unable to aim its antenna towards the Earth. All scientific equipment by that time will be already turned off, but the device itself will fly for a very long time in the cold of interstellar outer space, as a silent witness of human genius.