Ciao, Cassini: Craft to plunge into Saturn

CAPE CANAVERAL, Fla. — After a 20-year voyage, NASA’S Cassini spacecraft is poised to dive into Saturn this week to become forever one with the exquisite planet.

NASA is hoping for scientific dividends up until the end. Every tidbit radioed back from Cassini will help astronomers understand the entire Saturnian system — rings, moons and all.

The only spacecraft ever to orbit Saturn, Cassini spent the past five months exploring the uncharted territory between the gaseous planet and its rings.

On Monday, Cassini flew past jumbo moon Titan one last time for a gravity assist — a final kiss goodbye, as NASA calls it, nudging the spacecraft into a deliberate, no-way-out path.

During its final plunge early Friday morning, Cassini will keep sampling Saturn’s atmosphere and beaming back data, until the spacecraft loses control and its antenna no longer points toward Earth. Descending at a scorching 76,000 mph, Cassini will melt and then vaporize.

“The mission has been insanely, wildly, beautifully successful,” said NASA program scientist Curt Niebur. “I find great comfort in the fact that Cassini will continue teaching us up to the very last second.”

Telescopes on Earth will watch for Cassini’s burnout nearly a billion miles away. But any flashes will be hard to see given the time — close to high noon at Saturn — and Cassini’s minuscule size against the solar system’s second-largest planet.

Cassini discovered six moons — some barely a mile or two across — as well as swarms of moonlets that are still part of Saturn’s rings.

All told, Cassini has traveled

4.9 billion miles since launch, orbited Saturn nearly 300 times and collected more than 453,000 pictures and 635 gigabytes of scientific data.