NASA's Lunar Reconnaissance Orbiter, which is primarily used to take images of the Moon has been used to spy on Saturn from an extreme distance.

On October 13, 2021 the Lunar Reconnaissance Orbiter (LRO) snapped the above image of Saturn, and while the image could be somewhat disappointing to the eye, it's a representation of a significant technological achievement. The Lunar Reconnaissance Orbiter Camera (LROC) are line scan cameras, which means that instead of viewing the image as a whole it reviews it precisely line by line.
The LROC cameras have very short exposure times and are designed to take advantage of the speed of the spacecraft as it travels 1 mile per second. So, how did it take an image of Saturn? The orbiters cameras were pointed towards one side of Saturn and then to the planet's other side. The image that was taken showcases Saturn's iconic rings which appear to be above the equator. For those that don't know, Saturn's rings are only 10 to 100 million years old and mostly consist of water ice.
Phys.org explains, "LRO responded to the updated target by slewing to it at a specific rate across the planet. This rate is programed to optimize LRO stability and speed and resulted in a NAC exposure time of 3.82 milli-seconds. Since Saturn is much dimmer than the Moon (and Jupiter) and the exposure time is in effect set by the slew speed, we cannot detect the Saturnian moons as we did with the Galilean moons; they are just too dim."

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