schneiderism

This story started back in 1979 when the robotic space explorer Pioneer 11 did a fly-by of Saturn. This was followed a year later by Voyager I, and again in 1981 by Voyager II. These craft sent back primitive but compelling images, obviously far beyond anything we had yet seen from Earth, that created more questions than answers and compelled a generation to learn more. Now, Pioneer and the Voyager twins only captured images as they slingshot through the solar system on their way out as emissaries of humanity, so to speak. It would not be until 2004 that we would again visit Saturn, and this was when the robotic probe Cassini settled into Saturn’s orbit, the first craft to do so. Officially named the Cassini-Huygens, it is an international collaboration between three space agencies (NASA, ESA, and the Italian Space Agency) with 17 nations contributing to the building of the craft. There is an army of 250 scientists throughout the world studying the telemetry being beamed back to Earth. One of them is Carolyn Porco, a planetary scientist and leader of the Cassini mission who gave an excited, emotional, and amazing presentation at TED earlier this year. Definitely watch it. She showed some amazing images of Saturn, like the one here:

This Image was taken by Cassini as Saturn eclipses and is backlit by the sun. Stunning. Her focus, though, quickly moved to the moons surrounding Saturn and what Cassini-Huygens had discovered. The moon Titan stole the show, as Cassini dropped the Huygens probe to the surface to end decades of speculation of what that surface might be like. It has been a successful mission, and Huygens has sent back incredible imagery of an environment not that much unlike Mars, but with characteristics also quite Earth-like. Carolyn’s excitement by the implications of the imagery was readily apparent. The image below is one of my favorites taken by Cassini and is Saturn’s moon Tethys. That large crater that dominates the image is called Odysseus and it is about 400km across, roughly 1/25th of Tethys’ surface. On exactly the other side of Tethys is a series of large trenches cut into the moon’s surface and these were most likely the result of the impact that created the Odysseus crater. That’s cosmological drama.

Some intersting facts about Cassini-Huygens and Saturn to drop into conversation this week:

• - The total cost of the Cassini mission will be about $3.27 billion ($2.6 billion from the U.S.)
• - More than 5000 people worldwide have worked on or contributed to the Cassini mission
• - Saturn averages about 890 million miles distance from Earth
• - Cassini traveled nearly 2.2 billion miles to get to Saturn slingshotting off other planets
• - Traveling at the speed of light you could make it to Saturn in 84 minutes
• - Cassini took six years and eight months to reach Saturn
• - On the way it flew by and took images of Earth, Venus, and Jupiter
• - The atmosphere of Saturn is primarily hydrogen and helium
• - Saturn is a gas giant (made up mostly of gas) and is less dense than water
• - That means that in a large enough swimming pool, Saturn would float
• - Saturn has a core made up mostly of rock and ice with a radius of about 3700 miles
• - At its poles Saturn exhibits auroras similar to those on Earth

More about Cassini-Huygens and Saturn:

Cassini mission images

Cassini overview