Sunday, October 23, 2005
Some Links
Well, isn't this interesting!
It is being reported that the printer industry such as Hewlett-Packard has collaborated with the government to help identify counterfeiting and other criminal activity. In many laser printers an invisible dot matrix encoded with information is also printed on the document. With microscopes government investigators can glean information to enable them to track where the document originated. If a counterfeiter prints phony 100 dollar bills then he will also be printing his location and possibly even his identity right on the bill.The story is at Obligatory Anecdotes; the source is at Science Daily:
The Electronic Frontier Foundation of San Francisco said it had cracked the code in a widely used line of Xerox printers. The code is an invisible set of dots that contain the serial number of the printer, as well as the date and time a document was printed.As my mother used to say: "Well, ain't that special"...
With the Xerox printers, the information appears as a pattern of yellow dots, each only a millimeter wide and visible only with a magnifying glass and a blue light, the Washington Post reported.
The EFF said it has identified similar coding on pages printed from nearly every major printer manufacturer, including Hewlett-Packard Co.
I guess I'd be surprised if something like this wasn't done. After all, color laser printers are ubiquitous enough these days to make counterfeiting simple and cheap for nearly anyone.
Granted, our paper currency is a lot more sophisticated than it used to be, with watermarks and special inks and many other things; and all American paper currency has long been printed on special paper, available only to the U.S. Mint. Nonetheless: how often do you pay for something with a twenty, and have it accepted without a second glance?
I can understand why civil libertarians are (or soon will be) up in arms about this. Speaking for myself, I'm not overly concerned with the Federal government being able to prove that my documents were printed by me. But it is weird, to say the least.
(Oh, and don't try to print out the image above. I edited it a bit before I posted it. What secret messages did I embed therein? I'm not telling.)
(Hat tip: open post at Smash's Place.)
And here's another one, courtesy of Jeff Harrell, a first-rate blogger I don't read often enough. He points us to a snazzy new Website, created by NASA to explain how they intend to land men on the Moon by 2018:
Now, either you're intrigued and want to learn more, or I've already lost you. Some people just get bitten by the Moon bug (and the closely-related space-exploration bug); other people couldn't care less. I was bitten, hard, as a pre-teen, and I find, to my surprise, that I haven't lost the sense of wonder I used to get then.
Don't get me wrong -- it's a bold approach, and I actually do think that it's worth doing. An amazing number of techniques and artifacts of our modern civilization originated in the space program. Whenever you see something miniaturized, from computers to heart monitors, you can bet that it originated with NASA. And besides, we need a foothold off-planet, if only as an insurance policy. The Cold War may be over, but we could still muck up this planet pretty thoroughly if we're not careful.
Finally, it's worth doing if only as a way to fire people's imaginations and inspire them to great things. Do you realize that human beings have been staring at the Moon, wondering about it, for as long as we've been human? And do you realize that, in all those years -- perhaps 100,000 generations of people -- a total of twelve people, all Americans, have actually been there? They've walked on the moon, done experiments there, experienced the sheer wonder of walking on another planet, seeing the Earth above them in the sky. Six of them drove electric cars on the Moon. One of them brought a golf club with him. As of October 2005, eight of them are still alive.
Nonetheless, I wonder about NASA's devotion to the original plans. Yes, it's "new and improved"; yes, it's much more reusable than the original was; yes, it can take four men to the lunar surface, instead of two plus bored-guy-in-orbit. But the basic plan is the same: command plus service module, lunar lander in two stages, command module comes in for a "splashdown" landing (although it seems that land-based returns will now be possible).
Come on, people! What ever happened to horizontal takeoff and horizontal landing for spacecraft? Whatever happened to craft that can actually land under their own power, as an aircraft does (and as the Shuttle almost does)?
Or is NASA afraid to start with a completely clean sheet of paper, for fear of the R&D necessary (or, more accurately, of the cost of the R&D necessary)? A great pity, if so. (Update: see below.)
Keep your eyes on Burt Rutan, people. We will have regular travel to and from space, and permanent settlements outside of Earth's atmosphere, within the next twenty years. But will it be government activity, or private enterprise, that makes it happen?
(For a fictional account of how the latter might happen, read this book, if you can find it. I first read it when I was fourteen, and found it extremely inspiring.)
UPDATE: My buddy Rich, who has far more experience with aeronautical engineering than I'll ever have, answers most of my questions in his comment (below):
Daniel -- what happened to "horizontal" spaceflight is quite similar to what happened with pure-electric vehicle R&D in the 1990's ... the efforts ran into the laws of physics and the state of the art in materials technology.I stand corrected. I recalled that, back in the late seventies and early eighties, the idea of horizontal-takeoff spacecraft was intriguing -- take off like an airliner, not like a rocket, thereby letting the atmosphere do a lot of the heavy-lifting for you. But apparently I'm not up-to-date on the literature on the subject.
In particular, reliable and reusable heat shielding of a "horizontal" spacecraft, while still preserving its aerodynamic and payload capabilities, has proven quite elusive. After losing Columbia, NASA has had to take a step back in that area ... which is one of the major reasons I can see them developing this proposal, which offers both simplicity and protection for the heat-shielding systems.
If we want to return to the moon in the forseeable future, this is the most viable way of doing so.
On a side note ... while I do consider the accomplishments of the Rutan brothers quite remarkable, and have some hope they can achieve what you imply, keep in mind that they are not ahead of NASA when it comes to practical, orbital/lunar/interplanetary spacecraft designs.Fair enough. I do hope, however, that Scaled Composites will find other ways to push their work into orbital flight. (This isn't necessary, strictly speaking; if they can make suborbital flight cost-effective, the payoff for them can be enormous, even if they never achieve orbital capability. But I hope they do it anyway.)
SpaceShipOne was specifically designed for the suborbital X-prize competition -- it never got much above Mach 3, and the "feather" configuration shift it used to avoid heating problems at reentry would create problems if extrapolated for use in orbital flight, IMO.
From what I understand, the way SpaceShipOne avoided the heating problem was by using the feather configuration to decelerate the ship fast enough to avoid long exposure times at velocity/altitude combinations that would generate high heat. To do that with an orbital craft, this layman (an electronics expert, not an aerospace engineer) thinks that the necessary G-loads would greatly exceed human capacities for G tolerance ... if it even could be done in a way that would reduce heating to a level sufficient to eliminate the need for ablative heat shields or thermal tiles.
My gut tells me that NASA will work harder, and smarter, if they're afraid of being shown up by private enterprise. Besides, competition can be healthy. I'd love to see NASA doing the heavy lifting to put a space habitat into orbit... and Scaled Composites, or their licensees (or competitors!), doing their best to outbid NASA for cheap transportation there and back.
