"The spacecraft's final signal will be like an echo", Earl Maize, Cassini project manager at JPL, said hours before the last transmission was received.
"I hope you're all as deeply proud of this fantastic accomplishment", Maize said to the Cassini team in mission control after it lost contact.
"Cassini's finale tonight will certainly be a bittersweet moment, but I don't think of it like the death of a friend", Mr Nagle said.
The 22ft long spacecraft, launched from Cape Canaveral, Florida, in 1997, took seven years to reach Saturn. Then on its final pass by Titan this week, the moon gave Cassini just enough of a "goodbye kiss" to send the vehicle on its crash course with Saturn. During its broadcast NASA played a video clip of the Cassini Virtual Singers, spacecraft team members who belted out, "Tonight, tonight, we take the plunge tonight." to the music from "West Side Story".
The two sensors were part of the Cassini Plasma Spectrometer, or CAPS, a microwave oven-sized unit that was one of 12 scientific instruments on the two-story-tall Cassini spacecraft. Perhaps most tantalising, ocean worlds were unveiled by Cassini and its hitchhiking companion, the Huygens lander, on the moons Enceladus and Titan, which could possibly harbour life.
Cassini has also found evidence of an underground ocean on Saturn's sixth largest moon - Enceladus. Goal since it was of major scientific discoveries on our understanding of Saturn as the solar system, and since it was still in great shape, it has been extended to nine years.
The 22ft space craft has been flying through the solar system and orbiting Saturn for 13 years.
However, there's another reason for ending the mission in such a spectacular fashion: "We have the opportunity to do some really cool science", Bittner says. (NASA/JPL-Caltech/Space Science Institute) As it glanced around the Saturn system one final time, NASA's Cassini spacecraft captured this view of the planet's giant moon Titan.
Project scientist Linda Spilker noted Cassini has been running "a marathon of scientific discovery" for 13 years at Saturn.
The spacecraft discovered new moons around Saturn; the planet has 53 named moons and another nine unnamed moons, and there are many more small objects that might one day be confirmed as moons.
"So we're here today to cheer as Cassini finishes that race", she said. "We can not release any value yet", Iess says, "but this is the first indication that we have that probably the rings didn't form together with Saturn".
Nasa decided Cassini's mission should end this way long before the mission got to this stage. The mission team behind Cassini has planned to send the spacecraft into Saturn for many years now, in order to protect the planetary system the vehicle has been exploring.
Together Cassini and Huygens showed Titan to have a startlingly Earth-like landscape, with rivers, lakes and seas filled with liquid methane and ethane.
NPR's Adam Cole, who helped produce a video commemorating the spacecraft's life and times, says: "Scientists [were] anxious that when [Cassini] loses power, it could crash into a pristine moon, contaminating a place where we might someday search for life".