As I was watching the grand finale of Cassini and listening to the mission team talk about the accomplishments of the mission, I learned a little bit about propellors. Not your typical airplane propellor, but the name used to describe this fascinating feature in Saturn’s rings. Seeing Saturn’s rings from afar, or even relatively close with Cassini, we see the rings as perfect. How do we end up with strange features and imperfections like this one? Looking elsewhere in the rings, we can find clues. The first clue is the namesake of the mission itself. The Cassini spacecraft was named for...
I remember vividly my first astronomy class in university. Winter 2004, only months before the Cassini spacecraft was set to arrive at Saturn after a seven year journey. On several occasions in that class we talked about what we might see when Cassini reached it’s destination. The first dedicated mission to the jewel of the solar system, originally conceived right after the voyager flyby in 1982, would give us a chance to study more than just a planet, but an entire system of interaction between a planet and it’s moons. Beyond that, it included the Huygens probe, to land at...
It’s always funny explaining astronomical time to a non-scientist. I often get the craziest looks when I mention a million years as being a ‘blip on the radar.’ Perhaps there is some immortal alien race out there who would understand how nothing much happens on the scale of the universe in a million years. To humanity and our ever-accelerating advancement, a million years is thrice the age of our entire species. But I guess Einstein was right when he said that ‘it’s all relative.’ This brings us to Saturn, a planet as ancient as the solar system. Moderately old in...
I love false-colour images. They reveal detail that you can’t see in real life, but they also highlight things in an artistic way. For me it’s an excellent marriage of art and science, and as a communicator it helps me get concepts across in an accessible way. So when I saw the APOD image of Saturn from earlier this week, I had to discuss it. Saturn never has looked this way, and it never will. The colours are vivid and unrealistic, but they show the differences in three distinct but close wavelengths of light on the electromagnetic spectrum. All of...
With more than a decade of observations, the Cassini spacecraft has redefined our understanding of the ringed giant Saturn and its diverse moons. Continually working and returning new data, it has achieved significant scientific milestones, along with it’s partner probe Huygens, which dropped down through the thick clouds of mighty moon Titan’s atmosphere in early 2005. Along with a new scientific understanding comes views never-before-seen by human eyes, revealing the artful dance between the gas giant, its moons, and its incredible ring system. One of my favourite photos shows the incredibly beautiful symmetry of the rings. The rotational symmetry in...
Since it entered Saturnian orbit on July 1st, 2004, the Cassini spacecraft has changed our view of Saturn and its moons. It is a dynamic gas giant with unique and fascinating moons that have their own characteristics that make them seem more like small, rocky, planets than moons of a gas giant. Cassini has been delivering amazing science for over a decade, and it’s next journey lies in a polar orbit of Saturn, where it will dive through Saturn’s rings, giving the most detailed and close up views of the tiny ice particles that compose them. Before this journey, Cassini...
Every year, as the Earth revolves around the Sun, we pass an imaginary line directly from the Sun to Saturn. The Sun is on one side of us and Saturn is on the other. When two bodies are on opposite sides of the Earth like this we call it opposition. Saturn’s opposition for the year was on May 23rd, and even though it has been a few days, you can still see Saturn up pretty much all night. Along with opposition, we can clearly see the rings, but Saturn does wobble on a 29.5 year cycle, meaning there are times...
The first exoplanet ever discovered was 51 Pegasi b in 1995. It kicked marked the slow beginning of what would soon become the ‘exoplanet gold rush.’ It meant that for the first time, we had the technological capacity to discover new worlds, and science fiction soon became science fact. 51 Pegasi b was also a very strange planet. A massive Jupiter sized world orbiting very close to its home star. On one hand it was this characteristic that made it much easier to detect. On the other, it showed us that we did not understand planetary system formation as well...
No, he isn’t a zombie. He’s a long dead scientific pioneer. He discovered Saturn’s moon of Titan and was the first to suggest that Saturn’s odd ‘blob’ shape could be explained by rings around the planet. He was a pioneer of optics and developed a telescope with two lenses, more powerful than Galileos. He also characterized the motion of an ideal mathematical pendulum (with a massless cord and a length longer than its swing), and invented the pendulum clock as a method of keeping time. He had a few other contributions to astronomy, including the observation of individual stars in...
The seventh planet from the Sun is a boring one. The best photos we have of Uranus were obtained in January 1986 during the passing of Voyager 2, and they revealed a cold, pale-green, ball of Methane four times the diameter of Earth with very little visible activity. Since then, we’ve learned a lot about Uranus, and it’s far more interesting than we thought. It has rings, a magnetosphere, and numerous moons. It has a 98 degree axial tilt, meaning that the poles of the planet cycle through 42 years of sunlight and 42 years of darkness during it’s 84...
