For Jeff King: Rocket Fuel
>> Wednesday, October 7, 2009
Jeff King asked: What alternative rocket fuel do we have to look forward to, to help our stagnate space program to take the next big leap?
I don't know that new fuels are the key. With all our technologies, hydrogen/oxygen are still the most efficient of rocket fuels, but cryogenic support systems are expensive, complex and prone to failure. H/O and hypergolics (like hydrazine) dominate here in the US. Russia has an amazing launch record using almost exclusively kerosene-based rocket fuels (which have the advantages of liquid based throttle-ability without the problems of cryogenics). Hydrogen peroxide has also been touted as potential fuel.
But most if not all of the fuels we're talking about are effectively the same ones from 40 years ago. When it comes to lifting off the planet, we're still using traditional methods. However, once you're in orbit (or a transition orbit), there are alternate methods of propulsion, like for interplanetary travel, that move beyond the traditional fuels.
Among the possible methods of propulsion that have potential, however, there are several nuclear possibilities, including using radioisotope rocket, electric propulsion, and solar sails.
Yea traveling to other plants is what i was referring to. And from what I can gather, cutting down the time of travel is the only real way of conceiving this type of mission. Plus if we cut down the amount/volume of fuel we could use that space/room for vital equipment for long periods of space travel
Because the body will be affected by zero gravity in the same time frame, so speed is of the essence to success or viability for future mission... thx
I was hoping for Antimatter or wormhole travel, but maybe that is an entirely dif question/topic.
Antimatter and wormhole travel are based on theoretical physics, unproven and untried. They would require (a) things in the real world to be as we envision them in theory (which we don't know yet), (b) scientific breakthroughs that enable us to do theoretically impossible things like survive a going headfirst into a black hole or contain antimatter in some vessel without contacting it with matter. You can do that in fiction, but, in reality, there are limited means to do even test the notions.
In theory, the Hadron Collider was supposed to help with that, but, since it's still off-line, it's not.
NASA's not working on those because, without the technological/scientific breakthroughs (as well as a convenient local source for antimatter and/or black holes), you can't do anything with it. Without really knowing (a) if those constructs exist as we envision them, (b) how they'd act in reality and (c) the solutions to the attendant issues, can't be built into even an experiemental spacecraft.
Is this real...
http://www.spacedaily.com/news/solarsails-04a.html
if so, very promising.
i know it is old, but was unware of this.
Yep. Solar sails, in concept, have already been proven. The picture in your link was actually an artist's depiction of Cosmos 1 launched in 2005, but there was a launch failure and it was never deployed. They're working on raising money for Cosmos 2 now.
wow, i find that awesome. i have been reading about the speeds a craft like that could achive... just amazing.
One of my father's friends was big on solid rocket fuel. I have no scientific knowledge of what, exactly, that is, but he always complained that NASA had stopped doing research on it.
Any thoughts? Just another conspiracy nut?
Jeff King, I actually designed a solar sail in college.
The Mother, the US does the bulk of the solid rocket boosting worldwide, but neither the "engines" or the fuel have effectively changed from the ballistic missile days. They are used a great deal in military launches, sometimes as stages, frequently as strap on boosters, and, of course, the Shuttle uses them too (and they're planned for Ares use at this particular moment in time).
I'm not sure what you mean by research. Things haven't changed much and, personally, I'm not horribly fond of them. They have an advantage in that they're simple and generally considered reliable (largely due to simplicity), but they aren't throttle-able, once you start them you can't stop and they have, on numerous occasions, exploded spontaneously, limiting your options if they DO (often without warning). Oh, and they're super toxic.
I know Russia does almost nothing with them and that's actually pretty significant to me. Just my personal opinion.
I was very happy of the successful 200 kW VASIMR test-firing by you guys recently: http://www.theregister.co.uk/2009/10/05/vasimr_200kw_success/
VASIMR is one of the few plasma thrusters that has also some oomph behind it (where oomph = thrust), and I'd really like to see space-probes taking of using this technology!