NASA's Cassini probe to begin 'Grand Finale'

The final voyage of NASA's Cassini spacecraft, which has been in orbit around Saturn since 2004, will see the probe dive between the planet's rings before plunging into the atmosphere to destroy itself.

NASA's Cassini spacecraft has been hanging out in space for two decades, with well over a decade of that time spent exploring the space around Saturn, taking scientific readings, and teaching humanity more about the ringed planet than we had ever known before. Cassini gave us close-up views of worlds only glimpsed during previous flybys, revealed seven new moons orbiting Saturn, ice geyser plumes on Enceladus, methane lakes on Titan, spokes in the rings of Saturn, and much more.

"The Grand Finale is a brand-new mission", said Linda Spilker, Cassini project scientist at JPL.

"Because what we've learnt about the Saturnian system, the planet, its rings and its moons, has really rewritten the textbooks", he said.

"Cassini's own discoveries were its demise", said Earl Maize, the mission's project manager.

The exact origin of the rings of Saturn has perplexed astronomers for centuries but, using the latest technology, the pieces of the puzzle are gradually being put together by researchers unattached to the Cassini mission.

This mission does come with some risk, which is why NASA waited until the very end before undertaking it.

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Cassini was launched in October of 1997, taking nearly seven years to reach Saturn.

Cassini's last close flyby of Saturn's giant moon Titan is planned for April 22.

"Cassini will make some of its most extraordinary observations at the end of its long life". He added that mission team members are confident that Cassini will encounter only the smallest particles in the ring gap, and the probability of losing the spacecraft to an impact with something bigger is "less than 1 percent". For starters, these orbits will bring Cassini closer to Saturn's rings than it has ever been, so it will be able to study their age and composition.

Even on the final dive into the atmosphere, the spacecraft will continue to return data as it fights to keep its antenna pointing in the right direction.

The spacecraft will make detailed maps of Saturn's gravity and magnetic fields, revealing how the planet is arranged internally, and possibly helping to solve the irksome mystery of just how fast Saturn is rotating. "Flying this close to the rings of a planet, that's a once in a lifetime experience for a scientist".

NASA launched Cassini into space in 1997. It will also provide new details on the rings that could help pin down how they formed, whether from a moon that ventured too close to its parent planet or from material that never got a chance to gather into a moon.

  • Douglas Reid