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Magnetic Space Launches
DiZNoG writes "This CNN article discusses NASA experimenting with the idea of using Mag-Lev technology to launch payloads into space. Mentioned in the article is that the U.S. Navy is working on the technology for it's aircraft carriers to launch fighters. Unfortunately the NASA project is horribly underfunded ($30,000) for research. Cool technology, let's hope that the Navy research gets us a step closer to not burning all that Oxygen and Hydrogen to get to space...
let's hope that the Navy research gets us a step closer to not burning all that Oxygen and Hydrogen to get to space...
Yes, we must reduce emissions of deadly Dihydrogen Monoxide! It's already filling our rivers, streams and oceans, and has been found even in the ice of Antarctica! The time to act is now, people! Before our wells are full of this dangerous chemical!
Yeah, right. And exactly what would hold the
thing in place? A shitload of rockets?
"Source... The Final Frontier" -- keepersoflists.org
Is this what happened on your home planet?
Yup. And for a more manageable 10g, you'd need a 315km run to reach geosynchronous velocity. Of course, you'd also burn to a crisp in the atmosphere ;-)
The advantage of railgun / rocket sled launches is in getting you some of the way up to orbital velocity, but there's still a good long way to go. Basically, you can't reach orbital velocity while still inside the atmosphere, so you have to carry a bunch of fuel up with you whichever way you cut it.
Here's some handy dandy info for those who want to have a play with the numbers and have forgotten their Newtonian stuff:
Geosynchronous orbit is at 42,245m, which requires an orbital velocity of 7869m/s. Gravity is 9.81m/s^2
Distance = half of acceleration times time squared (s = 0.5 * a * t^2) and velocity equals acceleration times time, so time equals velocity divided by acceleration (v = a * t, t = v / a)
If you know the speed that you want and the acceleration that you can tolerate, this gives you:
s = 0.5 * v^2 / a (e.g. for 7869m/s and 98.1m/s^2, s = 0.5 * 7869 * 7869 / 98.1 = 315602m = 315km)
Or, if you know the distance you have and speed that you want, and want to know the acceleration you need:
a = 0.5 * v^2 / s (e.g. for 7869m/s and a 2km run, a = 0.5 * 7869 * 7869 / 2000 = 15480 m/s^2 or about 1578g!)
If you were blocking sigs, you wouldn't have to read this.
is the temperature of fresh ox blood. I've often wondered if US weather reporters need to perform some sort of ritual to calibrate their thermometers...
This makes me feel REALLY old, but the EML technology research has been going on for over 20 years. I recall the 1990 High School CX debate topic very well and spent most of the year debating EML launchers (prototyped on Sandia National Labs railgun). We spent the summer in the library in New Mexico visiting Sandia and UNM to research our cases. They were already launching coffee can-sized payloads at that time.
Some of the EML experiments from the late 80s and early 90s were visited at a 95 IEEE pulsed power conference: here. Of course, it's been a HOT topic since pre-85, when the first IEEE pulsed power conference was held.
We've been at the brink of maglev space launches for the alst 20 decades. Maybe it'll happen tomorrow. Probably not. There's basically no money in this sort of solution for defense contractors, so it generally languishes in congressional committees when it comes time to fund...
Oh well. It would be cheaper, cleaner, safer, and a whole helluva lot more fun at parties... but the same issues applied 20 years ago as today: it doesn't get funded b/c it's a public works-type solution to space. There's no money for Lockheed in something like that.
Magnets schmagnets, lets just tie a long rope to the space station and we can climb up, like in gym class.
Using Pounds is a way for NASA to save money...
;-)
As Pounds is a measure of weight rather than mass, the cost goes down as the weight reduces as the payload goes into orbit.
If you used Kilograms then you would be measuring mass which stays fixed, hence no cost savings
(Top Tip - Always buy a 2.2 Pounds of moon rock, never 1 Kilogram - You will get about 6 times as much rock due to the lower gravity on the moon)
wot no sig
I'm sure this was one of the technologies that you get in Sid Meyer's Alpha Centauri - so it must be workable!