According to Colwell

These pictures from my backyard show soft pink and green pastel hues at the perimeters of clouds west of Boulder. I’ve seen these colors many times, and they are quite dramatic through sunglasses. To get a particular color like those in these clouds requires that light at the wavelength corresponding to that color is scattered by the ice particles in the clouds much more efficiently than light at other wavelengths. Seeing these colors suggests therefore that the ice crystals are all nearly the same size and that that size is several times larger than the wavelength of the scattered light (about 0.5 microns). This is a case of diffraction where there is a resonance between the wavelength of light and the size of the particle.

Babel is a skillfully acted and produced movie that fails because the tragic circumstances in two of the three stories are brought about not by necessity but by the unbelievably bad decisions of the characters. And I do mean “unbelievably”, as in “no one would do those things”. The three stories are linked together, but the links are totally inconsequential to the events in each story. Nothing would be different about the stories or their impact if they were simply presented as independent stories. Nothing in the stories hinges upon people not being able to communicate with each other, counter to the implication of the title and the preview.

The preview shows us that Cate Blanchett’s character is shot while vacationing in Morocco. That is the critical event in that storyline, but it all comes about because a goatherder’s son decides to shoot at a bus. He does this knowing that he very well might hit it. The kid is not evil, does not hate Americans or foreigners, and is only doing it for target practice. I didn’t buy it. In another story, the live-in nanny for two young American kids takes them across the border to Mexico for her son’s wedding after being unable to find anyone to care for them for the day. Anyone who is wealthy enough to have a live-in nanny is going to have friends who can take care of those kids in an emergency, especially when they know from CNN that their parents are stuck in Morocco because one of them has been shot! And the nanny turns out to be an illegal immigrant! How did she think she was going to get across the border not once but twice with kids who are not her own? I could not get emotionally involved in the consequences of these messes because I didn’t believe anyone would ever make those decisions.

The world is full of tragic circumstances, so it is puzzling to me that this movie had such contrived and implausible circumstances on which to built its stories. I liked the acting in all three stories, and I found the third story about a deaf Japanese high school girl desperate for affection to work well on its own terms.

Saturn’s F ring exists on the very boundary separating the realm of rings and moons. Planetary rings exist because the ring particles are so close to the planet they orbit that they are unable to gravitationally stick together to grow into a moon. Being close to the planet means that there is a strong tidal force from the planet that tends to pull accreting particles apart. One way to look at this is to remember that all ring particles orbit their host planet on a distinct orbit, and the speed they travel on that orbit varies with their distance from the planet. Closer particles orbit slightly faster than more distant particles. Two ring particles that bump into each other (and they do so ever so gently, at a fraction of a centimeter per second) are on slightly different orbits around their planet, with the one closer to the planet moving slightly faster. This difference in orbital speed induced by the planet’s gravity is enough to overcome the gravitational attraction between the two ring particles when the particles are close to the planet. The region where this tidal inhibition to accretion is effective is called the Roche zone after French mathematician Eduard Roche, who first formulated this problem. Imagine running around a race track with a friend in two different lanes while holding hands. The strength of your handhold represents the gravity pulling two ring particles together. But you are obligated to run at a certain speed, and if you are on the inner lane, you will gradually pull away from your friend and break that bond. If you are on a giant racetrack (that is, farther from the planet) then the difference between your lane and your friend’s lane might be so small that your handhold can overcome the tendency of one of you to move ahead of the other.

Saturn’s F ring is right at the hairy edge of the Roche zone, about two and a half times the radius of Saturn from the center of the planet. Here, rings no longer have a nice uniform circular appearance, and moons and rings co-exist, though you might say they don’t co-exist very peacefully judging from pictures like the one below.

Image credit: NASA/JPL/Space Science Institute

Rings look circular precisely because of this different lap-speed phenomenon mentioned above. Particles a little closer will eventually lap their more distant neighbors, and a clump of particles like that seen in this image will quickly (years) smear out into a nice uniform ring like we’re used to seeing. The F ring is filled with strange structures due to repeated gravitational stirring from nearby moons Prometheus and Pandora. Originally dubbed “shepherd satellites” for their role in confining the F ring, a new nickname like “cheerleading satellites” might be more appropriate since their most dramatic effect on the F ring is the creation of waves as they lap the ring, just like cheerleaders excite a wave in a stadium (okay, maybe not just like cheerleaders). This cheerleading can cause some of the crowd of particles in the F ring to bump into each other a little more vigorously, producing new clumps of particles. Some clumps in the F ring may manage to stick together longer and form temporary moonlets because they are not so deep in Saturn’s Roche zone. These new moonlets also stir up the F ring producing strange ephemeral structures like the ones seen below.

Image credit: NASA/JPL/Space Science Institute

Christopher Guest’s latest keeps the same cast of self-important characters as his recent mockumentaries A Mighty Wind and Best in Show, but in For Your Consideration he presents them in a traditional fictional narrative rather than in documentary style. Guest plays the director of what is clearly a terrible movie, “Home for Purim”, about a southern American Jewish family in World War II dealing with a dying mother (played by Catherine O’Hara) and a lesbian daughter (played by Parker Posey). Bob Balaban and Michael McKean play the screenwriters. The premise of the movie is that an internet rumor gets started hinting that O’Hara’s character, Marilyn Hack (get it?), might get an Oscar nomination for her performance in “Home for Purim”. This rumor starts before the movie has finished filming and therefore before anyone with any sense has seen it. The rumor mill picks up a life of its own as the male lead, Victor Allan Miller (Harry Shearer), also starts to get Oscar buzz and the two make the rounds of the L.A. morning shows and Hollywood gossip shows.

Consideration generates some laughs from the preposterous behavior of its characters and from the absurdity of the movie they are making. “Home for Purim” features deep South accents mixed with bad acting and reading from the book of Esther along with heavy use of the Purim “gragger” or noisemaker as part of the tradition of this holiday. The movie’s publicist has only barely heard of the “World Wide Interweb”, Victor Allan Miller is auditioning for radio commercials in Oregon while filming “Purim”, and Marilyn Hack is best known for her portrayal of a cross-eyed blind prostitute twenty years ago. It is so far beyond credible that “Purim” would ever get made, let alone generate Oscar buzz, that it keeps Consideration from rising above the level of a simple exercise in mockery. In Guest’s Waiting for Guffman it was much easier to accept characters in a quiet midwestern town dreaming of fifteen minutes of fame than it is to imagine in Consideration that the entire Hollywood movie culture has simultaneously lost its collective mind. It would have been both funnier and more engaging to have this be about actors with at least some talent and a movie that is not laughably bad. The clips we see from the other Oscar-worthy movies in the world of Consideration are also atrocious. Perhaps Guest is trying to send-up all self-important actors and filmmakers. If so, it would have been more effective to have his actors be a bit less ridiculous.

The proximity of the mountains and the high altitude give Boulder Colorado dramatic cloudscapes, with frequent lenticular clouds forming as air moving eastward over the edge of the mountains rises due to the topography. The variety of clouds is quite impressive, especially for someone from Florida where simple puffy cumulus clouds are dominant. On the way home yesterday I saw the sort of colorful roiling clouds that outdid even some of Steven Spielberg’s over-the-top clouds (I’m thinking of Poltergeist, and, of course, Close Encounters of the Third Kind). I managed to get to the house and get my camera just minutes before the hour-long display ended with the setting sun.

Harold Crick, single, lonely IRS agent, hears the voice of author Karen Eiffel narrating his life as it happens to him. If he screams at the sky for the voice to stop, he simply hears the implacable voice of Emma Thompson describing her character screaming at the sky in frustration. The cinematic device of having a character hear his life narrated in the third person omniscient allows Crick to examine his own life as another person might see it. This casts a harsh light on his existence that acts as a catalyst for Crick to reinvent himself. Just as novels follow the arc of a character, by seeing his own existence in literary terms, Crick is forced put his life on a new trajectory. The critical question, he discovers with the help of a literary professor (played by Dustin Hoffman), is whether his life is going to be a comedy or a tragedy.

When he meets Ana Pascal (Maggie Gyllenhaal), a cute and rebellious baker (whom he’s auditing), he’s instantly smitten and she is naturally antagonistic toward him because of his professional duty to check her taxes. This smacks of comedy, but when he flubs his chances to court her, things seem to trend dangerously toward tragedy. The movie has a deft and understated tone even as it builds towards questions of life and death. Director Marc Forster (Finding Neverland, Monster’s Ball) allows his actors to shine without interference from gimmickry in a movie that is built on a gimmick. The screenplay is by Zach Helm in his first cinematic production, and he too keeps the movie about the characters and not the gimmick. How Crick is hearing his life narrated by Eiffel is immaterial, and the movie wisely doesn’t concern itself with that. The essence of the story is in the characters of Crick and Eiffel and how they get to know themselves in a way they never could before.

Borat can’t make up its mind what kind of movie it wants to be. As a result, it is an amalgam of three different movie ideas, each executed with mixed results. Movie 1 is a farce about a ridiculous foreigner, Borat, working his way across America so that he can marry Pamela Anderson. Movie 2 is in the style of “Candid Camera” or “Punk’d”, where Borat is a rude buffoon to elicit funny responses from passersby. Movie 3 is in the style of the correspondents’ reports on “The Daily Show with Jon Stewart”, where Borat interviews Americans and either provokes them (telling a group of feminists that women have tiny brains) or plays up their own prejudices to expose them. While each movie idea has the potential to be funny, the inconsistent nature of the movie diminishes the individual elements.

The movie pretends to be the documentary footage of a backwards foreigner learning about American culture for the betterment of his own country (nominally Kazakhstan, though of course it bears no resemblance to any real country). We are introduced to a producer, and though we never see the cameraman, Borat addresses the camera directly. When he is in principle alone and abandoned, we still see professional camera shots of his vehicle driving down the highway. Who took those shots, in the premise of the movie? Many of the people he encounters have been fooled into thinking that he really is from Kazakhstan and really is traveling across the country to learn about American culture. That is, they are not actors and are not reading from a script, and we, watching the movie, know this. For example, Borat befriends a prostitute in the mode of Movie 3, but later he has her pretending to be his wife not for the sake of other people in the movie, but for the camera and the sake of the fake documentary. She switches, in other words, from being one of the people being fooled by actor Sascha Baron Cohen into an actor herself in Cohen’s movie.

There are several scenes where Cohen behaves outrageously, but the response he gets is just what anyone would do when confronted with such behavior. Affecting gangsta rap behavior, he pulls his waistband below his ass, exposing ridiculous underwear, and goes into the lobby of a posh hotel spouting mildly obscene street slang. So the hotel staff ask him, and then force him, to leave. This is Cohen interacting with people in the mode of Movie 3, but the staff response is entirely appropriate and therefore not funny. If this were part of an attempt to tell a story (Movie 1), and the hotel staff were actors helping tell the story, then it could have been funny because we would be emotionally involved in the character of Borat. But we are constantly reminded that in fact we are seeing something more like Candid Camera, so we don’t care about Borat as a character at all: he is just acting that way to provoke people. Occasionally it is funny, but more often it is merely someone going around being obnoxious.

The annual Leonid meteor shower is predicted to have a surge around 11:45 p.m. EST Saturday November 18 with a rate of a couple meteors per minute. Meteors are the atmospheric phenomenon caused by the frictional heating of a meteoroid as it enters the atmosphere. Fragments that make it to the ground are called meteorites. Annual meteor showers occur when the Earth passes near the orbit of a comet. While the comet may be quite distant, comets are rather messy and tend to leave a trail of debris as they orbit the Sun. The debris is lost from the comet as the comet heats up when it approaches the Sun and its ices start to evaporate, sometimes forcefully enough to knock large chunks off the comet (see Hollywood’s visualization of this in Deep Impact (buy a copy, I’ll be happy to autograph it for you )). These bits of cometary debris continue on their merry way around the Sun, following a path very similar to that of the comet, but not exactly the same. Over the course of many orbits, the orbital path of the comet becomes relatively busy with debris so that whenever the Earth passes by the orbit it encounters the comet’s leftovers. Strong bursts in one of these meteor showers depend on the precise path of the Earth by the comet’s orbit as well as the recent history of the comet and its proximity to the Earth.

The Leonids are debris from the comet Tempel-Tuttle which takes 33 years to orbit the Sun on a highly eccentric orbit that takes it close enough to the Sun for it to be actively vaporizing for a relatively brief period each orbit. The last perihelion, or closest approach to the Sun (Tempel-Tuttle gets slightly closer to the Sun than the Earth’s average distance), was in 1998, so the Leonids in the few years after that were particularly spectacular. The shower is called the Leonids because the meteors appear to radiate from the constellation Leo. This is due simply to the direction in the sky that the Earth is moving around the Sun with a correction for the direction and speed that the meteoroids themselves are orbiting the Sun. Like driving through the rain, the meteoroids hit the windshield of the Earth’s atmosphere from the same direction. Unfortunately, at the predicted peak time, Leo is still below the horizon in the United States, so we may not see the full brunt. Nevertheless, if the sky is clear, it’s worth spending at least a few minutes looking up.

The Cassini mission at Saturn is going swimmingly, as my father would have said. The spacecraft is healthy, the instruments are healthy (yes, we do tend to attach human attributes to these machines), and the discoveries are piling up more quickly than we can report. One of the things that has struck me about the UVIS observations I work with is the tremendous advantage it is to have multiple observations from different vantage points, and at different times. The combination of the observations is truly greater than the sum of the parts. So I am hopeful that an “extended mission” or “XM” will be approved for Cassini to continue observing Saturn and its family of rings and moons for another two years after the nominal mission ends June 30, 2008.

In anticipation of such an extension, the project has been working on the trajectory the spacecraft will fly for the two year XM. The trajectory, called a “tour”, determines the viewing geometry available to the spacecraft. Because Cassini’s targets include Saturn’s many icy moons, the giant moon Titan, as well as the rings and magnetosphere, a wide variety of viewing geometries are desired. Clever use of gravity assists by Titan and natural perturbations to Cassini’s orbit due to Saturn’s aspherical gravitational field (Saturn is squashed by about 10% in the North-South direction because it (a) rotates in only 10.6 hours, and (b) is a big floppy gas-bag sort of a planet, with a bulk density less than water; this causes Cassini’s orbit to precess around Saturn rather than repeating perfectly) allow the tour designers at JPL to come up with a wide variety of tour options and to meet the observation requirements of a highly diverse set of scientific goals. A final decision on the XM tour is expected in early February. The two-year XM will allow Cassini to continue observations of all its science targets at Saturn in the same style that it is currently operating, namely very productively.

The spacecraft will still have power and fuel available after a two year XM, so I’m also hopeful for an XXM.

The Queen portrays the reactions of Queen Elizabeth II and newly elected Prime Minister Tony Blair to the death of Princess Diana in 1997 and the change that it brought to the relationship between the people of England and the royal family. Or perhaps the change was just in the queen’s understanding of her relationship to the people. Helen Mirren portrays the monarch, with James Cromwell as her grumpy husband, Prince Philip, who is even less willing to recognize and deal with the public outpouring of grief than the queen is. Secluded at their enormous Scottish estate of Balmoral, Philip’s plan for helping Diana’s sons (virtually invisible in the movie) is to take them deer hunting. Prince Charles, meanwhile, is equally broken up over the loss of the boys’ mother (whom, he pointedly tells his mother, was never afraid to show affection to her sons) and fear of the public reaction to his part in driving Diana out of the royal family.

PM Blair, meanwhile, has to balance the etiquette of dealing with the queen with the need to, as he puts it, “save these people from themselves”. But Elizabeth is a sympathetic character in this movie. Inheriting the role of monarch at the age of 25, her role transformed without her even realizing it. At least that is the out that the movie provides to explain her public bungling of the aftermath of Diana’s death. Stuck in an age where the monarch is apart and above her subjects, she failed to recognized that she now lives in a world full of royalty, namely celebrities. And the rules for celebrity behavior are decidedly different than the rules the queen had learned. Diana understood celebrity, and her death taught her family something about it.