ETA 2 days: Cassini begins its daring death dive towards Saturn

Nearly 20 years ago a spacecraft named Cassini-Huygens began its journey to the Solar System’s second largest gas giant Saturn to study the planet and its numerous moons.

On 15 September 2017, its mission will be terminated in the most triumphant way possible: a deep dive and eventual crash into the surface of Saturn.

It’ll be a sad moment for those vested in the craft, but Cassini has nonetheless been an invaluable tool to astronomers, scientists, and little boys hosting Goodbye Cassini parties in their back gardens.

We’re approaching #Saturn over the northern hemisphere in advance of first #GrandFinale dive through gap between the planet and its rings. pic.twitter.com/RaFA4C0FOw

— CassiniSaturn (@CassiniSaturn) April 26, 2017

According to an infographic published by the team’s Twitter account, the spacecraft’s exploits has contributed to nearly 4000 research papers, over 630GB of raw data, and has embarked on over 162 deliberate flybys of Saturn’s numerous moons. All this after travelling well over seven billion kilometres from Earth.

In its 13 years orbiting Saturn, the craft has observed a number of incredible phenomena.

Cassini’s primary objectives included studies of Saturn’s ring structure, the planet’s perplexing magnetosphere, and its massive moon Titan.

That list eventually grew to include the likes of Enceladus — an icy moon that features a tell-tale vapour plume at its south pole — and Rhea — a moon that was believed to have a simple ring system of its own.

These objectives shifted as the craft’s mission progressed, but is now drawing to an end as Cassini’s fuel and plutonium power cell diminishes.

14 hours watching the plume at Saturn’s moon Enceladus, our last dedicated observation of this singular scene https://t.co/EqLPb6MsbO pic.twitter.com/hW3BVUExcz

— CassiniSaturn (@CassiniSaturn) September 10, 2017

At the end of April 2017, it began its Grand Finale, a sequence of 26 daring dives between Saturn and its ring to better investigate the structures, and the planet, more closely.

After passing Titan for the final time on 12 September, Cassini is now positioning itself for its final trick: a face-dive into the Solar System’s second largest planet.

At present, it’s hurtling towards the gas giant at over 100 000km/h relative to Earth, and is around 1.1-billion kilometres from Saturn itself.

After offloading its remaining data to the Goldstone, US team, Cassini will be sending and receiving signals to and from Australia’s branch of NASA’s Deep Space Communication network in Canberra eight hours before it hits Saturn’s atmosphere.

By 2pm SAST on 15 September, Cassini will be no more. But its legacy will undoubtedly live on forever.

Feature image: NASA/JPL