RIP Cassini. Job well done!

NASA received its last data transmission from the Cassini spacecraft at 4:55:46 a.m. PDT (7:55:46 a.m. EDT, 1146 GMT) on Friday, Sept. 15, before losing contact with the probe as it hurtled into Saturn's atmosphere and broke apart.

Cassini orbited Saturn for 13 years before its fiery grand finale. NASA officials expect that Cassini broke apart about 45 seconds after that final transmission, due to the intense friction and heat generated by the fall.

Cassini's descent into Saturn was intentional. The spacecraft was rapidly running out of fuel, after spending nearly 20 years in space, and NASA scientists decided to make use of the mission's inevitable conclusion. By crashing into Saturn, Cassini had the opportunity to see what the planet's upper atmosphere is made of, and that's the data that the probe sent back to Earth during its final few moments of life. Read more here.

Related: Mystery of Saturn's Epic Storms; Cassini's Greatest Images