Voyager 2 photographed Neptune in light so dim that some exposures lasted seconds or even minutes, while the spacecraft was racing past the planet. To stop the images smearing, engineers programmed the spacecraft itself to compensate for the motion, turning the whole probe into its own image-stabilisation system.

On 25 August 1989, Voyager 2 passed Neptune, the last planet of its tour and the most distant. The images it returned are still the sharpest close-up views of Neptune that exist. No spacecraft has visited the planet since. Neptune is about 30 times farther from the Sun than Earth. According to NASA, it receives [...] The post Voyager 2 photographed Neptune in light so dim that some exposures lasted seconds or even minutes, while the spacecraft was racing past the planet. To stop the images smear