Chances are you’ve heard that NASA’s Cassini mission around Saturn will come to an end in September this year. This weekend, the spacecraft made its last flyby of the fascinating moon Titan as it moves into the final phase of the mission.

This flyby, the 127th of Titan, saw Cassini come within 979 kilometers (608 miles) of the moon’s north pole. As it did so, it was busy studying the surface, including investigating the moon's lakes and seas.

As it flew past, it also snapped some final images of this flyby, the last close-up view we’ll get of Titan for the foreseeable future. There is no follow-up mission to Saturn or Titan planned at the moment.

"Cassini's up-close exploration of Titan is now behind us, but the rich volume of data the spacecraft has collected will fuel scientific study for decades to come," said Linda Spilker, the mission's project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California, in a statement.

^{All these images are unprocessed views of Titan. NASA/JPL-Caltech/Space Science Institute}

Titan is Saturn’s largest moon by far, bigger than all its other moons put together, so its gravitational pull has been used throughout the mission to change the orbit of Cassini, enabling it to investigate targets of interest. This particular flyby put Cassini on its Grand Finale, a series of swooping orbits that will take the spacecraft between Saturn and its rings for the first time.

Cassini will make its first dive into this unexplored region tomorrow, April 26, sending back images and data to Earth the day after. But while there’s plenty more Saturn science to come, this is the end for our exploration of Titan.

Since Cassini arrived at Saturn in 2004 and dropped the Huygens lander onto Titan in 2005, we’ve learned that this world is the only place other than Earth with bodies of liquid known to be on its surface. These are in the form of liquid hydrocarbons, with the moon seemingly hostile to life as we know it, but it may have a habitable ocean under its surface.

^{NASA/JPL-Caltech/Space Science Institute}

There will be no shortage of lamenting for Cassini when the mission comes to an end on September 15 this year. Cassini will be sent crashing into Saturn’s atmosphere, to prevent it hitting one of the habitable moons and contaminating them as it runs out of fuel.

For Titan though, it’s goodbye and goodnight. We’ll get a final look at the moon the day before the Cassini mission ends, on September 14, from a much greater distance. But this is our last close-up glimpse of one of the most fascinating worlds in the Solar System.