Today, Sept. 15, Cassini crashed into Saturn after 13 years spent orbiting the ringed planet. The bus-size spacecraft's instruments got hot, and its thrusters fired frantically to keep its antenna pointed at Earth to send those last few bits of data. But, ultimately, Cassini melted and broke apart in the fiery heat of its 69,000-mph (111,000 km/h) plunge into Saturn.
And if you haven't been paying attention to Cassini's mission at Saturn, well, you've missed out. As I recently told Space.com's parent company, Purch, in a blog post, Cassini is a mission that just keeps on giving.
The probe explored space for nearly 20 years. It reshaped our view of Saturn and discovered tantalizing water geysers on the moon Enceladus and methane seas on fellow Saturn moon Titan, changing ideas about where life might be able to grab a toehold in our solar system. Along the way, the spacecraft made countless other discoveries about the planet's rings, moons and atmosphere.
And then there are the photos. Spectacular, jaw-dropping views of Saturn's weird hexagon and strange moons Mimas (the Death Star, anyone?); Iapetus (is that a walnut or moon?); and Pan, which sure does look like a tasty ravioli.
The probe beamed its final photos of Saturn to Earth on Thursday. There won't be more like them until we decide to go back.
Cassini truly was a flagship mission. Powered by plutonium (which led to some protests when the probe launched in 1997), the $3.9 billion spacecraft slingshotted around Venus twice and Earth once before traveling on to Jupiter to accelerate enough to reach Saturn in 2004. The spacecraft traveled 4.9 billion miles (7.9 billion kilometers) during its mission, circled Saturn 293 times, discovered six moons and observed dozens more. It dropped the European Space Agency's Huygens probe on Titan, the first-ever landing in the outer solar system.
And even faced with imminent death, Cassini persevered. With scorching-hot temperatures searing its instruments, the hardy probe held on during the dive into Saturn. Spacecraft operations chief Julie Webster has proof. She told reporters today that Cassini's interior was a comfortable room temperature until the probe's signal went silent. And that signal itself lasted a full 30 seconds longer than anyone expected.
So, while facing the end, Cassini went out in a literal blaze of glory. And even after its science has fueled thousands of research studies, the mission's legacy will live on as more discoveries are sifted from the 635 gigabytes of data the probe collected.
Full disclosure: I did not expect to feel an emotional impact from Cassini's dive into Saturn.
The mission was amazing to be sure. The photos, fantastic. But Cassini was a mission that was just always there. I took this wonderful mission, this gold and white explorer in the realm of giant planets, for granted.
And yet, two memories make Cassini shine bright. They're not so much about science as exploration.
In 1997, before Cassini ever launched into space, I went to a talk at the Griffith Observatory in Los Angeles (I was studying print journalism and astronomy at the University of Southern California then). It was there that Griffith astronomer E.C. Krupp and John Casani, then Cassini's project manager at Jet Propulsion Laboratory (if my memory is correct), gave a talk on the promise of exploring Saturn.
We were finally going to see the gas giant up close! We would see the rings and moons in ways the Voyager probes never could. And it was all beginning that year! That sense of adventure was inspiring.
I left that Cassini talk determined to be about astronomy. I even told Krupp this as he signed a copy of his then-new book "Skywatchers, Shamans & Kings" (which I still have on a shelf at home).
And today, two decades later, I do write about astronomy and Cassini itself. And that full circle of personal space exploration is just amazing.
Thank you, Cassini, for launching not just a mission of Saturn discovery, but also a more personal journey for me. [Cassini's Last-Ever Photos Come Down to Earth]
That brings me to the second memory. It's a new one.
Just a few days ago, I saw Saturn through a high-powered telescope from Central Park at Starfest, an event hosted by the Amateur Astronomers Association of New York. The planet was as stunning as ever, a golden-beige bauble with its iconic rings. Then, my daughter took a turn.
For Zadie, age 8, it was her first-ever glimpse of Saturn. Titan shone as a brilliant speck nearby.
"I just saw Titan!" she screamed to anyone in earshot.
I told her that Cassini was there now, but not for long, that the probe would crash into Saturn and be gone. It was kind of sad, but Cassini had been there for a long time and had taken such amazing photos.
"Well, I hope we can build another one," she said.
So do I, Zadie. So do I.