Random Linkage 10/10/09

'Trash Can' Nuclear Reactors Could Power Human Outpost On Moon Or Mars
‘NASA has made a series of critical strides toward the development of new nuclear reactors the size of a trash can that could power a human outpost on the moon or Mars.’
(Or small communities in, say, Iraq or Afghanistan.)

Trips to Mars in 39 Days
‘Using traditional chemical rockets, a trip to Mars – at quickest — lasts 6 months. But a new rocket tested successfully last week could potentially cut down travel time to the Red Planet to just 39 days. The Ad Astra Rocket Company tested a plasma rocket called the VASIMR VX-200 engine, which ran at 201 kilowatts in a vacuum chamber, passing the 200-kilowatt mark for the first time. "It's the most powerful plasma rocket in the world right now," says Franklin Chang-Diaz, former NASA astronaut and CEO of Ad Astra. The company has also signed an agreement with NASA to test a 200-kilowatt VASIMR engine on the International Space Station in 2013.’

Massive MESSENGER Mercury Mosaic
'Just in time for MESSENGER's third flyby comes a mosaic from the second flyby! This absolutely enormous mosaic of Mercury's globe represents 66 individual narrow-angle camera frames on Mercury captured by MESSENGER as it departed from its second encounter. Its departure view on its recent, third flyby would have been basically the same if it had not been in safe mode. The mosaic was assembled by Cassini imaging team member Jason Perry in his free time, and I hereby thank him for the four days of effort that it took him to establish a control network that would make his software behave and assemble this gorgeous view. I'm glad he could do it because it was way beyond my expertise! Now does anybody else want to dive into the Planetary Data System for the color data taken using the wide-angle camera during departure so we can produce a nice color version of this view? There was a 3-by-3 WAC color mosaic at about the same time...'
(If this doesn't inspire you to write some Mercury-based fiction, I don't know what will.)

Blasted into space from a giant air gun
'When Jules Verne wrote about a gigantic gun that could be used to launch people into space in the 19th century, no one expected it to become a reality. Now physicist John Hunter has outlined the design of such a gun that he says could slash the cost of putting cargo into orbit.'

Pumpkin cannon could be ultimate big-boy toy*
'John Gill tucks a gray pumpkin under his arm and climbs to the top of a rusty ladder. He opens a hatch on the side of a steel pipe, drops the pumpkin inside and sprays it with magenta paint.
'"So we can find it later," he says.'
(Via Neatorama.)
*(No kidding.)

Where It's At

Tom Waits provides the answer to that old chestnut, 'Where do you get your ideas?'

"You know how it is," he says. "If you're a writer you know that the stories don't come to you, you have to go looking for them. The old men in the lobby: that's where the stories were. And then when the record label would send me on tour, I always resisted checking into the usual places. I'd step off the bus and look for the hotels named after presidents." Hotels named after presidents, he argues, guarantee a certain grubby authenticity. "The Taft!" Waits says with relish. "You could usually rely on finding a Taft in every town. Take me to the Taft! You walk in and there they are: the old men in the lobby."

Wham!

Just watched the coverage of the impact of the LCROSS spacecraft on the Moon, following the impact, a few minutes earlier, of the Centaur rocket stage it had been shepherding. The impacts, in a permanently shadowed part of a crater at the Moon's south pole, have thrown up plumes of material; measurements of the plumes are being analysed right now to see if they contain any water. If they do, it's good news for those who want to press ahead with a return of manned landings to the Moon; if they don't, it could mean that there aren't any ice deposits in those shadow regions after all, or that LCROSS and the rocket stage hit dry spots. In any case, it's a tremendous techical achievement.

What struck me was the enormous gap between the behaviour of the NASA scientists and their fictional counterparts in films and TV shows. No fevered arguments between brilliant mavericks and unimaginative bureaucrats about last-minute make-or-break adjustments to the spacecraft's trajectory; no nervous breakdowns based on flashbacks to childhood trauma; no instant and triumphant cry that millions of tons of water had been found. In short, no drama, just quiet and calm competence, a short round of applause when LCROSS hit its target, and a brief subdued talking heads panel.

Well, that's reality. But what's also real is a couple of spacecraft slamming into the Moon within a few minutes of each other with pinpoint precision and at twice the speed of a bullet, throwing plumes of debris ten kilometres above the surface. The future of manned missions to the Moon hangs into the balance. And the official TV presentation has all the excitement of the opening of a new telephone sales centre on the Watford Ring Road. I'm being a little unfair - there were plenty of press releases, and NASA Ames put on a show for impact night - but given the general public's indifference, and NASA's reliance on tax dollars, it's a shame that its own coverage was so low key. Surely there must be some way of sexing up the work of its scientists without distorting it?

One Ring To Bind Them

All over the news right now is what is probably going to be #1 in a long list of Things I Wish Had Been Discovered Before I Started Writing The Quiet War And Gardens Of The Sun.

Discovered by the Spitzer space telescope and visible only in infrared light is a vast ring tilted at twenty-six degrees to the Saturn's equatorial plane - the plane in which the more familiar ring system and the inner moons orbit. It's very very big, this ring, circling Saturn at a distance of 13 million kilometres: if you look at Saturn from Earth, imagine that it's sitting inside a ring that is twice the apparent diameter of the full Moon. Factor in the relative distances of the Moon and Saturn, (384,000 kilometres v. the minimal distance, at opposition, of roughly 1300,000,000 kilometers), and you'll realise that this is a very big structure indeed: the biggest known ring in the Solar System

It's very big, but it's also very tenuous. More tenuous than even the vacuum inside electronic vacuum tubes: there are on average twenty grains of icy dust in each cubic kilometre of this giant ring. For good reason, its discoverers are calling it the Ghost Ring. It's no coincidence that it shares the same orbital inclination and distance as Saturn's moon Phoebe; it's almost certainly composed of material knocked off that small and eccentric moon by meteoritic impacts. Phoebe is an odd little moon; not only is its orbit steeply inclined, it's also retrograde - it travels in the opposite direction to the inner moons. Images taken by the Cassini orbiter as it passed Phoebe on its approach to Saturn show an irregular and heavily cratered body, with slivers of bright ice showing through a dark outer crust of carbonaceous material. It's similar in composition to Kuiper Belt Objects, in fact, and was probably captured by Saturn when something perturbed its orbit and it wandered in towards the Sun.


There's speculation that the material in the Ghost Ring has contributed to the distinctive colouration of the outermost of the large moons, Iapetus. Famously, Iapetus is bright on one side and dark on the other, a property spotted by the man who discovered it, Giovanni Domenico Cassini, in the seventeenth century. Now, it seems that the dark sooty material from the ring has been swept up by Iapetus's leading hemisphere over a couple of billion years.


But is the Ghost Ring really the largest ring in the Solar System? Saturn has many other small irregular moons in wide eccentric orbits. Most belong to collisional families and are probably fragments from a larger body that was shattered by some impact after it was captured by Saturn's gravity: the Inuit Group; the Norse Group; and the Gallic Group. Phoebe belongs to the Norse Group. The moons in the Gallic Group orbit even further out. Could they, too, have generated a ghost ring?

A Film I'd Dearly Love To See

Thom Anderson's Los Angeles Plays Itself, an argument assembled from film clips that use actual locations in LA. Plays on the festival/arthouse circuit, will probably never surface on DVD because of copyright issues, alas.