According to Colwell

I’ve decided to support Barack Obama for President. I am convinced that he has the best chance to restore America’s standing in the world. I also think that he has the best ability to work with members of both parties in congress to help pass some desperately needed legislation at home to undo as much as possible of the damage done in the last 7 years to our constitutional rights, environment, health care, education, and the working class. While the differences between the Democratic candidates are minor in comparison to the gulf that divides them from the Republican candidates, there are significant problems I have with many of the other Democratic candidates. I cannot get over Clinton sponsoring a bill outlawing burning the flag. I also think she is very divisive, and that will hinder her ability to make needed reform. I was also put off by Edwards’ flat-out dismissal of gay marriage, even though I like him overall and he is my second choice after Obama. Richardson was even worse on the subject of homosexuality, claiming it was a choice before making the redundant statement that he is “not a scientist”.

Frank Oz directed this light British farce that throws a cranky old uncle in a wheelchair, a pompous lazy brother, a hypochondriac, and a gay little person into what should be a quiet family funeral. Some home-brewed hallucinogenic drugs and potty humor (my favorite!) are thrown in for good measure. The mix is generally successful, producing many laughs and one or two very funny scenes, as the responsible middle-aged son of the deceased struggles to maintain decorum as things break down at their country house.

I wasn’t sure how this movie could do anything that hadn’t already been done by the excellent movie, For All Mankind (1989), which also chronicles the Apollo Moon missions exclusively using NASA footage and the voices of the astronauts who flew them. In the Shadow of the Moon does bring a new and valuable perspective to those missions and their effect on the world. Unlike For All Mankind, here we see the astronauts today and here their thoughts as they look back almost 4 decades on their historic voyages. They are thoughtful, personable, and interesting. The most poignant moment is hearing Michael Collins, the Command Module pilot of Apollo 11 (who orbited, but did not land on, the Moon), recall the worldwide sense of unity and accomplishment after their mission. People from all nations took pride in an accomplishment of the human species. He notes wryly that that sentiment was ephemeral.

Here it is: thanks to the new searchable video archive on The Daily Show’s web site, Jon Stewart making fun of our use of the word “dirt” in describing the composition of Saturn’s rings with the famous ultraviolet image I generated when Cassini arrived at Saturn on July 1, 2004.

The Cassini Project Science Group met this week at the Jet Propulsion Laboratory in Pasadena, the 43rd in a series of three-per-year where various members of the project, from NASA Headquarters to the spacecraft operations team to mission planners and scientists. This meeting coincided with the tenth anniversary of Cassini’s launch on October 15, 1997. We marked the occasion with a cake and some group pictures and then immediately got to the business of how Cassini will die.

Cassini is now in the final year of its nominal four-year mission, though a detailed plan for a two-year extension has been proposed and is awaiting final approval from NASA. But the time to figure out what will happen even after that two year extended mission (the “XM”) is now, given the time it takes to plan the complicated trajectory of the spacecraft through the Saturn system. Dubbed the “XXM”, this secondary extended mission would nominally conclude with the end of the mission.

The spacecraft is remarkably healthy and has sufficient resources to continue operating for many years, so there is a long list of possible options for the XXM. The scientific drivers for the XXM argue for a significantly longer XXM than the two-year XM so that features that change slowly can be studied. A Saturn season is 7 years long, so at the end of the XM Cassini will have observed about one season. To study Titan’s seasons (which march in lock step with Saturn’s), seasonal changes in Saturn’s atmosphere, and seasonal changes on Saturn’s rings (expected to affect production of spokes as well as the temperature of the particles), there are strong scientific reasons to have the XXM go for an additional Saturnian season. Studies of the vapor-spewing moon Enceladus for a long time period would tell us about variability in the activity of this intriguing moon. We still have a lot to learn about how the activity of that moon works. Studies of the magnetosphere will benefit from seeing changes over the course of the 11-year solar cycle. There is a lot of work to do before a decision is made on the Cassini XXM, but the potential is there for dramatic new discoveries by observing the planet and its moons and rings for more than a decade to see how things evolve on that timescale.

One more example of variability in the system centers around Saturn’s F ring. This unusual ring shows clumps that come and go, and it is strongly perturbed by nearby moons Pandora and Prometheus. The F ring seen by Cassini is quite different in many ways than the ring seen by Voyager 25 years ago. The number of strands is different, and the frequency and morphology of clumps within the main F ring core is quite different between the Voyager era and the Cassini era. With a lengthy Cassini XXM, we could actually observe these kinds of changes occurring. One possible reason for these changes is the changing orientation of the eccentric (non-circular) F ring with respect to its nearby shepherd moon Prometheus, also on an eccentric orbit. The period for the change in the alignment of pericenters of the orbits of the F ring and Prometheus (the points where they are closest to Saturn) is 17 years. The F ring is fundamentally intriguing because it is at the boundary between rings and moons, where tidal forces barely succeed in thwarting accretion of moons. Without the gravitational stirring of Pandora and Prometheus, perhaps long-lived moonlets would form in the F ring. A long-term observing campaign of the F ring in a lengthy Cassini XXM would illuminate the processes of satellite accretion and gravitational stirring by the moons and how that affects accretion.

As for the eventual “end of life” of Cassini (and yes, that’s what it’s really called), there are many possibilities, including a Galileo-like crash into Saturn.

I’m at the Cassini Project Science Group meeting in Pasadena this week, so my morning hotel routine involves motel buffet breakfast in the room in front of the morning news. At 7:00 a.m. I started with CBS’s “The Early Show”. In their lead-in to the morning’s news, they made a big deal about a picture of a fire where the shape of the flame bears a zeroth order resemblance to blob with a pointy thing at the top and a pointy thing at the side that some people have decided looks like former Pope John Paul II with a pointy hat and a pointy finger blessing someone. The anchors were quite excited at this amazing occurrence, so I promptly changed the channel to “The Today Show” on NBC where I was treated to the exact same nonsense. This is not only not news, it’s not anything. This was taken from video meaning either 30 frames of footage per second (NTSC) or 25 (Pal/SECAM), so if someone filmed this fire for even only one minute, there are over 1500 pictures of fire to choose from, and probably many more. I’m more surprised they couldn’t come up with a frame that showed a stronger resemblance to something.

I mentioned the upcoming insult to the state of the civilization with NBC’s “Phenomenon” earlier, but Lifetime apparently beat them to the punch. Check out the Skepchick’s hilarious review of their psychic show.

At this week’s annual meeting of the Division of Planetary Sciences of the American Astronomical Society in Orlando, a special session was devoted to Saturn’s moon Iapetus and its dramatic terrain marked by an equatorial mountain ridge and alternating regions of bright white ice and carbon black. It has long been thought that the explanation for the dark material covering roughly half of Iapetus is that dust knocked off more distant moons of Saturn is swept up by Iapetus as it orbits Saturn. One problem with this hypothesis, though, is that the distribution of dark material does not cover just the leading hemisphere of the moon. The pattern looks more like that of a baseball, with the bright water ice wrapping around the poles and the dark carbon-rich material wrapping around the equator.

Image Credit: NASA/JPL/SSI. Click the image for image details.

John Spencer, a scientist on the Cassini Infrared Spectrometer (CIRS), and colleagues have developed a thermal segregation model that nicely explains the dark/bright pattern on Iapetus. In a nutshell, the idea is that you start by having Iapetus plow through the dark dust migrating inward from the dark outer moons and coating the leading hemisphere of Iapetus. The dark terrain gets hotter than the clean bright water ice because it absorbs more radiation from the Sun, just as dark asphalt gets hotter than concrete. Because it is warmer, water ice underneath that dark material evaporates through the thin coating of dust and recondenses on cooler parts of the moon. This transports ice to cold areas which are shielded from the incoming dust and keeps them very bright and removes bright ice from areas that have been darkened by dust. The result is the dramatic black and white landscape seen in the most recent pictures returned by Cassini. Cold, bright areas collect bright water ice from the warm, dark areas, and dark areas lose water ice to the bright areas. There are, therefore, no shades of gray.

Image Credit: NASA/JPL/SSI. Click the image for the full resolution image and caption.

Image Credit: NASA/JPL/SSI. Click the image for the full resolution image and caption.

One of the cool things about the thermal segregation model described above is that it can be simulated on a computer and the migration of bright material can be visualized. Starting with an assumed initial distribution of dust on the moon, Spencer calculates that it would take about 100 million years for the surface to get to its current distribution of bright and dark terrain. If more time passes, the dark area spreads further than is observed. This age is probably related to the rate at which meteoroids “garden” the surface of Iapetus by punching through the thin (< 1 meter) layer of dark material and mixing it in with ice underneath. So the distribution of the bright and dark terrain give a clock that helps us also understand the cratering history of Iapetus.

There remains a puzzle about getting the dark material to Iapetus in the right amounts from the outer irregular moons of Saturn. These moons, such as Phoebe, are presumed to be captured by Saturn rather than having formed with Saturn, like Iapetus did. They may have formed further from the Sun where the composition had a greater proportion of carbon-rich compounds leading to their darker color.

The warm glow I felt after watching the latest episode of my favorite TV show, The Office, was quickly extinguished by an ad for a new TV show on NBC that would, if I were a man of principle, make me boycott the network. Billed as a reality show, “Phenomenon” is co-hosted by charlatan Uri Geller who will judge contestants’ magic tricks. Not having seen the show, I will reserve judgment on just how misleading and misguided the show is. According to tvweek.com, the co-host Criss Angel, a traditional magician “will lend a more skeptical voice to the proceedings.” But also according to tvweek, NBC will both invite viewers to figure out how tricks are accomplished and figure out “whether any of the mentalists might have actual psychic talent.” Groan.

I loved this movie. I haven’t seen a movie I loved this much in a long time. It is a magical piece of filmmaking. Director Julie Taymor tells a story of love and war, perfectly intertwining songs by the Beatles into a visually rich tapestry. To say it is a musical with Beatles songs risks making it sound smaller or like less of a work of art than it is. Which is not to imply that the music is not a huge part of what makes this movie so special. From T. V. Carpio’s hauntingly lovelorn rendition of “I Want to Hold Your Hand” to race riots over “Let It Be” to the uplifting “Hey Jude”, the music of the Beatles is an integral part of the tapestry that Taymor has created.

Jim Sturgess plays Jude from Liverpool, England, who leaves home to find his G.I. father in America. There he falls in with Max (Joe Anderson), the misfit son of a wealthy family and the brother of Lucy (Evan Rachel Wood). The social upheaval of the sixties swirls around and engulfs Jude, Max, and Lucy. Lucy becomes a passionate protester of the Vietnam war and Jude discovers his talents as an artist while they share an apartment in New York with Sadie (Dana Fuchs), who belts out songs such as “Why Don’t We Do It in the Road” and “Helter Skelter” with her band. To say more about the story doesn’t serve the movie, which creates an atmosphere with its songs, choreography, and cinematic composition while telling the stories of Max, Jude, and Lucy. There are a lot of good movies coming out this time of year, but the next one I want to see is this one again.

Although it feels like any attempt to describe this movie will diminish it, that is only because for me it is a work of art, and my hastily composed review will not be able to do it justice. Superficially one can compare it to Hair for its pop-music soundtrack and Vietnam backdrop, and to Moulin Rouge for its musical love story and colorful cinematography, but it is its own unique creation. Sturgess, who at times evokes the young Paul McCartney with his Liverpool accent and boyish features, gives a simple and touching performance, as does Evan Rachel Wood. The actors sing their own songs, frequently bringing a totally new emotional quality to them. Let it Be brought tears to my eyes, and Hey Jude gave me goosebumps. This is a movie that deserves to be seen, and should be seen on the big screen for the greatest impact. But I will definitely be buying the DVD.

On the Cassini project we try to spread the word about the amazing discoveries being made by this spacecraft at Saturn, and no one has a better bag of visual goodies to share than Carolyn Porco, head of the Cassini imaging team. Here is a video of one of her presentations with a whirlwind tour of some of the highlights from the mission.