I remember as a young boy watching Columbia take off and was inspired by the Space Shuttle – Now a piece of space history this amazing graphic I found in Pinterest gives the top to bottom of the Space Shuttle!
Today is the end of era and a project that has lasted around 30 years, given us a spectacular insight into one of the most beautiful objects in the solar system. Today is when the Cassini mission finally ends by plummeting into Saturn’s atmosphere and will be destroyed by re-entry and the intense pressure of it’s atmosphere.
When Cassini was first devised and started development started Ronald Regan was still president of the United States, Voyager 2’s final calling had not yet taken place and the internet was not widely used. The world was a very different place. Launched in 1997 and passing by Venus and Jupiter on the way to Saturn it saw in the new millennium on the way to it’s destination. Arriving after a seven year journey in 2004.
It’s mission was bold, to launch and land a small probe – Huygens onto the surface of Saturn’s’ largest moon Titan and run experiments to see what it’s surface and atmosphere are like while the Cassini orbiter relayed all the data back to Earth. After a short time the Huygens probe would stop operating, leaving the lone Cassini orbiter to carry on gathering data on Saturn and it’s system. Initially this was to only be for a few years, but two extensions have seen it last until 2017. Now, becasue of the orbiter’s dwindling fuel supply it will dive into Saturn’s atmosphere on September the 15th after a series of atmosphere skimming ring dives between the planet and it’s rings dubbed ‘The Grand Finale’. Cassini will be burned up in Saturn’s atmosphere becoming part of the planet, destroyed to stop it contaminating any of Saturn’s potentially life harbouring moons. This will ensure they are preserved untouched for future missions.
On the 15th October 1997 under the veil of night, Cassini was launched on the start of a seven year journey to Saturn on a course that would take it past Venus and Jupiter before arriving at Saturn in 2004.
On the 1st July 2004 Cassini entered orbit around Saturn and immediately began sending back pictures and data. One of Cassini’s first jobs was to map out the terrain of Saturn’s moon Titan so that a suitable landing site could be found.
On the 25th of December 2004 the Huygens probe was released from Cassini and began it’s approach and descent into Titan’s atmosphere. Titan is Saturn’s largest moon and is the only moon in the solar system with a thick methane atmosphere. This discovery was made by the Voyager 1 flyby mission and since then the possibility of liquid methane lakes and the possibility of some kind of life being able to exist on Titan has fascinated scientists.
Huygens landed on Titan on the 14th of January 2005 on it’s way down it spent about 90 minutes descending through Titan’s atmosphere. Taking pictures that were relayed back home via the Cassini spacecraft.
Huygens is the first and currently only spacecraft to land on a world in the outer Solar System. Once the small craft had landed it took the first pictures of the surface of this mysterious world.
The Huygens probe was expected to only have enough battery life for a few minutes on Titan. As it turned out Huygens lasted about 90 minutes, took pictures and analysed the surface. The stone seen in the picture are made of water ice and the red film is an outer layer of Methane. It was anticipated that Huygens could encounter and indeed land in a lake of Methane and was designed to be able to survive this. As it turned out it found no evidence of this. Since then, data returned from Cassini suggests these Methane lakes do exist particularly at the poles of the moon.
The Huygens probe is the first and currently remains the only man made object to land on a world in the outer solar system.
The Cassini orbiter lasted much longer than the little Huygens probe, much longer than it was originally meant to. The original mission was to observe the planet during it’s Equinox which occurred in 2009. The mission was extended to observe the planet at it’s summer solstice in 2017 which gave the orbiter another 155 orbits of Saturn and further observations of Titan and Enceladus. In that time Cassini has made observations on aurora at it’s poles, much like we have here on Earth.
At the poles, the clouds were found to form a hexagonal shape. This alone has kept scientists busy finding an explanation.
The magnificent rings of Saturn have been observed ever more closely in the last months as Cassini carries out it’s last flyby’s.
The majestic beauty of them hides a highly complex structure, shaped and formed by Saturn and it’s orbiting moons.
The size of the objects forming the rings sorted into a seemingly orderly fashion with larger like ice towers on the outer rings..
Gravity waves forming them into waves as you might find in water on Earth.
Cassini has observed many of it’s moons in closer detail than ever before, giving us a greater insight into how this planet and it’s system was formed.
But the shining star of Saturn’s moons has been Enceladus. It’s surface showing signs of old and new activity and the greatest discovery being of it’s plume of water ice, shooting into space.
Keep an Eye on us
Despite the distance, Cassini has been keeping an eye on us too from time to time:
The tiny dot is all of us – once again put into perspective we are tiny, living on a spec in the cosmos. But Cassini has looked back at the planet from where it came for the last time…
As space probes go – Cassini has had a good running, but Cassini is at Journey’s end:
In order to preserve the purity of Saturn’s moons and not contaminate them with bacteria Cassini takes it’s plunge into Saturn’s atmosphere today. It will forever become a part of the planet which it helped it’s creators to study. Saturn and it’s majesty has forever captured human fascination and will continue to do so. As the tool which has brought us that much closer to the ringed planet Cassini has also captured our imaginations and a little of our hearts.
While it may not be preserved for all eternity like the Voyagers, Cassini’s legacy will last, long after it’s demise and what it has brought us will forever be remembered. As it takes it’s plunge it will send us back data and images of Saturn, closer and more intimate than we have ever had before. It will go where no human can or maybe ever will go.
That’s a crowning achievement and a fitting last act for perhaps one of the most successful and awe inspiring spacecraft ever built.
Farewell Cassini, we know you’ll do us proud one last time.
More information on the Cassini mission can be found on NASA’s Cassini page:
On the 20th of August 1977 it started – Voyager 2 was launched. Then on the 5th of September the twin spacecraft Voyager 1 was launched. Despite being the second to be launched Voyager 1 was names number one as it would arrive at it’s destinations before it’s sister craft.
On the 5th March 1979 and the 7th of July 1979 respectively they arrived at their first destination. For the first time we could see Jupiter and it’s moons in high quality. Even though they only flew past they found Volcanoes on Io, Jupiter’s rings, Europa’s ice cracked surface and more moons to add to it’s already large number.
After this they both went on to Saturn, Arriving on the 12th of November 1980 and August the 25th 1981 respectively.
They found a frozen world, which much like Jupiter had storms, we saw the rings of this world in more detail than ever before and it’s largest moon, Titan was found to have a thick atmosphere.
At this point Voyager 1 was flung from the solar system by Saturn’s gravity, Voyager 2 continued the mission to the last of the outer planets alone.
So far every planet had it’s surprises, and Uranus was no exception. On the 24th of January Voyager 2 made it’s lonely flyby and a planet that was almost completely featureless. Magnetic instruments found it was like the planet had been knocked on it’s side, both the rings and the planets magnetic field were side on to the other planets.
Miranda, one of it’s moons had a crazy mashed up surface, broken up by gravitational pulling. Voyager 2 added more moons to the planets number.
On the 25th August 1989 Voyager 2’s final visit in our solar system had finally been reached.
Neptune was again a very different world, made mostly of Methane this beautiful blue world showed off the great black spot – a storm that looked like an eye looking out at you. With Winds faster than the speed of sound this was not all Neptune revealed.
Neptune’s largest moon Triton was found to have active ice volcanoes, introducing us to the concept of cryo volcanism. Voyager found some faint rings and more moons for the blue giant.
After Neptune, there wasn’t much or the Voyager probes to do, February 1999 Voyager 1 took a last look back at the solar system and the planet from where it came and took a last picture – a portrait of the solar system.
In 1999, Voyager 1 passed Pioneer 10, becoming the furthest man made object in space.
In 2004 and 2007 respectively the spacecraft encountered the terminator shock as they left the solar system and entered interstellar space. They are now on their way to the stars. Carrying with them records and messages from humanity from who or whatever might encounter them.
Despite being launch 40 years ago their mission may never end, ambassadors to eternity to the species that made and launched them hoping to make their mark in the universe. If left alone these two incredible machines will outlive not only the race that made them, but also the planet from where they came.
Now that it truly incredible.
No ownership claimed on images Credit to NASA and JPL.
A blog about life, the universe and some things that happen in it…