Category Archives: Technology and Society

Don Korycansky of the University of California, Santa Cruz, and Catherine Plesko of the Los Alamos National Laboratory in New Mexico simulated blowing up asteroids 1 kilometre across. When the speed of dispersal was relatively low, it took only hours for the fragments to coalesce into a new rock.

“The high-speed stuff goes away but the low-speed stuff reassembles [in] 2 to 18 hours,” Korycansky says. The simulations were presented (pdf) last week at the Lunar and Planetary Science Conference in Houston, Texas.

So you have to have a big enough bomb to really do the job. I think there are better, more controllable ways.

Media Criticism, Space, Technology and Society

Here We Go Again

March 5, 2010 Rand Simberg 96 Comments

Every time there’s a test of a scramjet, there’s associated overhype about how great it will be for space access. The upcoming X-51 flight is no exception:

Ms. Waldman said in her report that as scramjet technology is developed testers believe that in the near future it could be used to aid warfighters as a weapons delivery system. She said officials believe that in the future the scramjet technology will make space access easier.

“The application really is all about space lift,” Mr. Brink agreed, and said, “This is the one, I think, in the Air Force Research Lab we’re most excited about.”

Mr. Brink pointed out that they currently transport payload into space with the shuttle, which has to carry all of its oxidizers for the propulsion concept. He said the shuttle is a pure rocket system and said if they can incorporate scramjet engine technology into the space lift systems, they wouldn’t have to carry the oxidizers and could carry more payload instead.

Yeah, if there’s any payload left after you count the weight of the engines, which have terrible T/W compared to rockets, and all of the extra drag you incur staying in the atmosphere to collect the oxygen. I’ve discussed this more than once in the past. I’ve never seen a hypersonic airbreathing conceptual vehicle design that was an improvement in performance over a rocket for a space transport, at least if there was any analysis more serious than the above performed on it. Scramjets have plenty of utility for military applications. I wish that people selling the program didn’t always feel the need to oversell it. And if we had a smarter space media, they’d get called on it.

Technology and Society

The HondaJet

March 4, 2010 Rand Simberg 8 Comments

A review, by Glenn Reynolds, over at Popular Mechanics. A commenter claims that the engine development is having certification problems, but I don’t know how credible the commenter is.

I found this interesting:

Honda is also saving development money by taking advantage of modern computer power. Fujino notes that it’s possible to do serious design work on a laptop nowadays, where not long ago it took an expensive engineering workstation. And Honda is making heavy use of simulations, with a sophisticated whole-aircraft simulator that allows real parts to be swapped in and tested against virtual parts and vice versa, allowing many stages of refinement before parts ever reach the test-flight stage.

I wonder why these kinds of development-technology savings aren’t making their way into the spacecraft design world. But they probably are, actually. It’s one of the reasons that SpaceX has accomplished so much for comparatively little money. And when you’re on a cost-plus contract, you can always find other ways to spend the money.

Administrative, Technology and Society

Graphics Card Question

February 28, 2010 Rand Simberg 11 Comments

So my Samsung LCD monitor gave up the ghost (less than a couple years old, I think), and I went out to Frys to get a new replacement. I was looking at the displays and some of them looked like crap (blurry letters). I asked the salesman, and he said that they were being fed with VGA analog, whereas the sharp ones were digital (DVI or HDMI). If I were the manufacturers of those monitors, I’d be pretty unhappy with that situation, but I digress.

Anyway, I determined to not only get a replacement monitor, but to upgrade my video card as well to digital output. So I bought a new LG 21.5″ screen, and an MSI card with an NVidia N220GT engine, and a gig of DDR2 memory.

I got home, put in the card, and it turned out not to work without having to update Linux drivers from NVidia. But in changing it out, I also noticed that the old card (also an NVidia, with 128M of memory) had a DVI output, so I didn’t really need the new one in terms of digital output support. So I’m running with it now.

Question: I’m not a gamer, and don’t do anything really graphics intensive, such as video processing. Is there any point in updating drivers and reinstalling it, or should I just take it back and get my sixty bucks back? Will I see any performance improvement from it?

[Monday morning update]

Thanks for all the input in comments. I don’t need any of the things that y’all say the card will help with, so I’ll be taking it back. If I ever do need it, I’ll get a better one, cheaper, at that time.