Jupiter. Saturn. Uranus. Neptune. Each of these giant planets is the center of its own miniature solar system. Each is spectacularly beautiful and scientifically fascinating, which are reasons enough to explore them. But by studying the giant planets and their rings and moons, we can also learn about the forces that operated during the formation of our own solar system, as well as the origins of the hundreds of new extrasolar planetary systems that we discover every year.
And their moons are worlds in their own right. There are at least 16 outer planetary moons that would be called dwarf planets if they orbited the Sun rather than a planet. Two (Jupiter's Ganymede and Saturn's Titan) are larger than the planet Mercury, and one (Triton) is probably a captured Kuiper belt object.
But it is challenging and expensive to explore the outer planets, and missions to the outer planets take a very long time to develop, fly, and operate. Cassini will be orbiting Saturn until 2017, and Juno will operate at Jupiter from 2016 to 2017. After that, it's not clear if anyone will be sending a followup mission to Saturn or Jupiter or its moons, or an orbiter to survey the Uranus or Neptune systems. And there is a critical shortage of the isotope of plutonium that is needed to generate power for outer planetary missions.
Time for my quarterly foray into the Cassini archival science data! The very first image I downloaded from the January 1, 2013 data release presented an interesting challenge to my image processing skill. I'll show you the pretty picture of Enceladus and then explain how I processed it.
Posted by Björn Jónsson on 2013/01/22 06:04 CST
What is the highest resolution global Jupiter mosaic that includes a satellite transit that can be assembled from Voyager images? Satellite transits are especially beautiful when the resolution is high enough for some details to be visible on the satellites so I decided to check this. And I was remarkably lucky.
Join Casey Dreier and Emily Lakdawalla as they are joined by Dr. Meg Schwamb from Yale University. They will discuss the latest announcements from the American Astronomical Society 2013 conference and Dr. Schwamb's research in outer solar system bodies.
A recently launched Earth-observing satellite is using the stars to practice its pointing, and caught a neat animation of Jupiter.
Join us for our weekly Google+ Hangout Thursday at noon PT / 2000 UT. This week, I'm excited to have as a guest Sarah Hörst. Sarah is a postdoc at the University of Colorado whose current line of research involves experimental work on the complex atmospheric chemistry of Titan. She is also applying to be an astronaut!
Remember the amazing photo of Saturn's north pole that I posted yesterday? Now, thanks to an amateur image processor, it moves, and the motions of the individual clouds within the belts are mesmerizing.
A sharp-eyed amateur noticed two images of Titan taken 20 months apart from nearly exactly the same perspective, and they illustrate how the shifting of Saturn's seasons has brought change to Titan's atmosphere.