The Voyager mission included two probes — Voyager 1 and Voyager 2 — which NASA launched in 1977 within a few months of each other.

They took about 50,000 pictures of the planet in total, which greatly exceeded the quality of the pictures scientists took from Earth, according to NASA.

The pictures taught scientists important facts about the planet's atmosphere, magnetic forces, and geology that would have been difficult to decipher otherwise.

Since it wouldn't come across another planet on its ongoing journey, NASA switched off its cameras after its flyby of Neptune to conserve energy for other instruments. 

As its last photographic hurrah, Voyager 1 took 60 images of the solar system from 4 billion miles away in 1990. 

After this picture, NASA switched off Voyager 1's cameras to save energy

NASA could switch the probes' cameras back on, but it is not a priority for the mission.