Cassini: An End To A Journey

Oct 2, 2017 By Rachel Kenney
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On September 15, NASA scientists gathered to watch the final moments of what had been a revolutionary twenty-year journey.

As they looked on, a spacecraft called Cassini plunged into the atmosphere of Saturn, the planet it had been circling for over a decade, burning up upon entry.  The mood was nostalgic as these scientists marked the end of an incredible mission. 

Let’s take a look at Cassini and its momentous journey...

Cassini's Mission

In 2004, after a seven-year journey through space, Cassini, a cooperative mission between space agencies in the United States and Europe, arrived at Saturn. Although there were no humans aboard the spacecraft, Cassini was carrying a "passenger." This passenger was named Huygens, and it was a European probe. This probe was the first manmade object designed to land on a planet so far away from Earth's atmosphere.

After releasing Huygens on Saturn, Cassini continued to orbit Saturn, collecting information about the planet's rings, atmosphere, and its many moons. The spacecraft sent back breathtaking pictures and valuable information to the scientists waiting eagerly back on Earth. One picture that Cassini sent back of Saturn's moon Mimas looks suspiciously like the Death Star from Star Wars! 

Cassini also sent back evidence of a possible underground ocean on another one of Saturn’s moons, Enceladus. The possibility of an ocean could mean the moon is able to sustain life, most likely in the form of tiny microorganisms.  

Originally, the Cassini mission was scheduled to last about five years, however, the scientists and engineers that designed the spacecraft included backup systems and technology that allowed Cassini to fly for longer. Much longer, in fact...Cassini was able to explore space for thirteen years, eight years longer than planned. In total, the spacecraft was in space for over nineteen years! Can you imagine being in space for that long?

An End to a Journey

Despite the advanced technology of Cassini, it finally ran low on fuel after 13 years of exploring. Since there are no gas stations in space, scientists used the remaining amount of fuel to send Cassini on one last assignment.

On April 26, 2017, Cassini embarked on its final mission. The spacecraft plunged closer to Saturn than it had been throughout the rest of its mission, traveling between Saturn and its rings an astonishing twenty-two times! This had never been done before because it is an incredibly dangerous area of space. Since Saturn's rings are made of chunks of rock and ice, they could be damaging to a passing spacecraft.

However, since Cassini was destined to be destroyed anyway, the scientists controlling Cassini were able to take these risks. During this part of the mission, Cassini transmitted information that will help scientists understand how Saturn's rings were formed and about Saturn's gravitation and magnetic fields.

On the final dive through the rings, Cassini entered Saturn's atmosphere. Although it burned up during reentry, it's antenna continued to transmit information to NASA until the very last moment. Although Cassini’s mission is over, the things we have learned from Cassini have helped us understand the universe a little better.