The first close-up photo of a Saturn satellite

NASA's Cassini spacecraft flew close to a small Saturn satellite, named Daphnis and took the clearest picture of it ever.

On January 16, the Cassini spacecraft captured the most detailed picture of Saturn's Daphnis satellite . This is a small satellite, 8km wide and has a 42km wide orbit around Saturn. Its trajectory is called the Keeler Gap .

The most detailed picture of Saturn's Daphnis satellite.(Photo: NASA / JPL-Caltech).

NASA called Daphnis a wave-making satellite , because when the satellite orbited Saturn, it stirred up dust and surrounding rocks with a weak gravitational force, creating an orbit around it.

If you look closely at the image, you will see a small white line below the left corner of the satellite. It is a wave made of matter that is stirred by gravity.

These waves are not flat, but are stirred up. Another image of the Cassini ship taken in August 2009 clearly shows this.

Wave details created by Daphnis.(Photo: NASA / JPL-Caltech).

NASA is trying to capture as many valuable images as possible, because Cassini is expected to end this year after 13 years of Saturn orbit since 1997.

At the end of its mission, Cassini will crash into Saturn's thick clouds and bury itself permanently there.

At the end of 2016, NASA drew a new flight trajectory for Cassini so that it could capture unprecedented images of Saturn's satellites.

Small satellite Daphnis creates waves when flying in Saturn's orbit.

On this day in April 2017, Cassini will begin his death. It will rotate on Saturn's north pole, fall down, across satellites, and eventually burn like a meteor when it falls into Saturn's atmosphere. It is expected to be September 15, 2017.

Why didn't NASA let Cassini continue to fly after finishing his mission like the Voyager spacecraft - now flying off the Solar System? Because two icy satellites Enceladus and Titan are capable of surviving liquid water, the potential for life exists, so NASA wants to avoid the risk that Cassini will crash into these two satellites, causing them to become infected with germs from Earth.