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Cassini makes last fly-by of Titan

Cassini on April 21 made its last fly-by of Titan as the spacecraft is prepared for its final 22 orbits of Saturn.

The flyby also put Cassini on course for its dramatic last act, known as the Grand Finale. As the spacecraft passed over Titan, the moon’s gravity bent its path, reshaping the robotic probe’s orbit slightly so that instead of passing just outside Saturn’s main rings, Cassini will begin a series of 22 dives between the rings and the planet on April 26. The mission will conclude with a science-rich plunge into Saturn’s atmosphere on Sept. 15. “With this flyby we’re committed to the Grand Finale,” said Earl Maize, Cassini project manager at JPL. “The spacecraft is now on a ballistic path, so that even if we were to forgo future small course adjustments using thrusters, we would still enter Saturn’s atmosphere on Sept. 15 no matter what.”

The flyby zipped past Titan only a little more than 600 miles above its surface.

Pioneer cover

From the press release: From the moment he is handed a possibility of making the first alien contact, Saunders Maxwell decides he will do it, even if doing so takes him through hell and back.

Unfortunately, that is exactly where that journey takes him.

The vision that Zimmerman paints of vibrant human colonies on the Moon, Mars, the asteroids, and beyond, indomitably fighting the harsh lifeless environment of space to build new societies, captures perfectly the emerging space race we see today.

He also captures in Pioneer the heart of the human spirit, willing to push forward no matter the odds, no matter the cost. It is that spirit that will make the exploration of the heavens possible, forever, into the never-ending future.

Available everywhere for $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.


  • Orion314

    Goodbye to a superb mission. I wish they could have done a dive thru the rings to see it close up.

  • mpthompson

    Orion314, that would have been cool. Imagine a probe that would orbit beyond the rings and then slowly lower its orbital height until it could dance among the snowballs that comprise the ring material.

  • Orion314: Read the article that I linked to. They will be making multiple dives through the rings during these final months.

  • Joe

    This is the kind of science and type of mission that NASA is good at, building giant rockets(Sls) not so much.

  • Orion314

    re: “between the rings” I read that to be through the Cassini Division , or inside the the C ring and Saturn > I thought JPL/NASA was dead set against any actual ring impact for fear of possible satellite contamination.

  • LocalFluff

    The rings, those visible with binoculars from Earth, are fantastically thin, only about 10 meters thick!
    About 3% of the rings’ volume is mass. If the spacecraft covers one square meter, a dive through the rings would hit 30 liters of ice the in the 1,000 liters (10x1x1 meters) of ring volume it would pass through. Throwing a bucket of ice on Cassini at several kilometers per second would certainly destroy it. Cassini will not get close enough to resolve any of the ring particles, they are too small from a safe distance. A close up mission to the rings would be more like a surface lander on a microgravity asteroid. Landing on the protected trailing side one of the tiny shepherd moons would be nice in order to have a close look at ring particles.

  • Orion314

    Having a mission for a lander on one of the shepherding moons would be one helluva rendezvous !

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