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Electric Rockets Set To Transform Space Flight
An anonymous reader sends this quote from an article at Txchnologist:
"The spectacle of a booster rocket lifting off a launch pad atop a mass of brilliant flames and billowing smoke is an iconic image of the Space Age. Such powerful chemical rockets are needed to break the bonds of Earth's gravity and send spacecraft into orbit. But once a vehicle has progressed beyond low-earth orbit chemical rockets are not necessarily the best way to get around outer space. That's because chemical propulsion systems require such large quantities of fuel to generate high speeds, there is little room for payload. As a result rocket scientists are increasingly turning to electric rockets, which accelerate propellants out the back end using solar-powered electromagnetic fields rather than chemical reactions. The electric rockets use so much less propellant that the entire spacecraft can be much more compact, which enables them to scale down the original launch boosters."
Tesla would love this shit!
Or at least a meadow.
Mooooooooooooooooooooooooooo.
This is old technology and the benefits of this have already been realized in many satellites. There is literature going back well over a decade documenting the trade space.
The best part about living where I live is that they are building VASMIR engines down the street. It would be a long walk, but I could still walk to a freaking starship drive factory.
213 million six foot power strips daisy chained together...
crazy dynamite monkey
This piece piques one of my pet peeves, the confusion between scientists and engineers. Scientists do not build rockets--engineers build rockets. Even if a person trained in, say, physics, is designing a rocket, that person is effectively acting as an engineer.
I object to attempts to glorify certain kinds of engineers by calling them scientists. There is no such need to glorify engineers--they are glorious in their own right. Calling them scientists is a slap in the face and an insult.
Engineering and science could hardly be different. Engineers put things together; scientists take things apart.
I've actually been following ion powered (and all space flight) for a long time now and have wondered that ever since Deep Space 1 (no, not a TV series) "proved" the technology worked (that was one of its main jobs, it was a technology demonstrator) they didn't use ion engines on the space craft that used RTGs.
In particular New Horizons has travelled billions of miles coasting to Pluto, 99% of the time in hibernation despite the fact that its plutonium powered RTG is generating electricity whether used or not (it's not a reactor, it is always "on"). Considering the distance it has to travel, an ion drive could've really sped things up (or conversely allowed it to brake, and orbit Pluto!). Cassini might not have been such a good choice because maybe having the drive on doesn't allow good scientific observations (Cassini doesn't have its instruments on a scan tilt platform) and anyway the many delta - V changes might have required more thrust than the very weak ion drives can provide.
Actually, maybe ANY probe headed further than the moon or mars would find this useful. Juno, the Jupiter orbiter had huge solar panels which, during the cruise phase could have powered a decent ion engine. Messenger, the Mercury orbiter, although not going "far", had a huge delta-V requirement and had access to plenty of solar power.
Oh well, at least more and more probes like DAWN use this. I would presume when we return to the outer planets with any really ambitious probes (Europa lander/sub, Titan balloon/boat) they'll use this.
Someday, when we talk about sample return missions and the delta-V requirements at least double (and the fuel requirements go up geoemetrically!), ion drives (or their derivatives like the Vasimir drive) will be essential.
The HS601 and its XIPS system is technically electric since it is an Ion propulsive device. The above FTA is more about plasma thrust, but again all these concepts have been around for 50yrs: it's well known higher specific impulse == more acceleration for space flight == a better engine (and ions have more impulse than anything chemical)...
Turns out I was wrong. I made myself sad. Here's the technology that might actually transform space flight.
http://www.adastrarocket.com/aarc/
http://en.wikipedia.org/wiki/Variable_Specific_Impulse_Magnetoplasma_Rocket
The guy who invented it is an ex-Astronaut and VASIMR (or its tech underpinnings) was his PhD thesis at MIT for Applied Plasma Physics. I guess what I'm saying is he isn't a crank.
I built an ion rocket in 6th grade that was suspended from a string, and would increase the height to which it swung every time the high-voltage transformer was pulsed. Deep Space One had an electric rocket. These have been around awhile.
www.backwoodsengineer.com
Stardate 45280.4
My crew and I have just left Earth's orbit, it took a mere 15 minutes to accelerate enough to reach escape velocity. Unfortunately, we ran out of batteries the moment we passed the moon and are now waiting for the Vulcans to come rescue us. Unfortunately, there are no electric charding stations out past the great-divide so we will have to be taken back earth where our crew will double the number of lithium ion batteries.
"That's the way to do it" - Punch
I've long since given up on there being any semblance of proper research done in such articles, particularly when a nod might have to be given to anyone outside the US.
I'm no expert in the history of solar electric ion propulsion systems, but believe that NASA's Deep Space-1 mission in 1998 was (I think) the first to use SEP as its primary post-launch propulsion, as several subsequent NASA missions, including Dawn, as discussed in the article.
However, several European Space Agency missions have also used similar systems, including the ARTEMIS satellite in 2001 to get itself to geostationary orbit, the SMART-1 mission to the Moon (launched 2003, ended in a deliberate crash onto the Moon in 2006), the GOCE gravity-mapping mission, and the BepiColombo mission to Mercury (due for launch in 3 years) will be using one. The Japanese Hayabusa-1 asteroid sample return mission also used one.
Just trying to set the record at least a little straighter ...
A better approach is the Electrodynamic tether. Basically, create a linear motor against the earth's mangnetic field. This can only be used in orbit, BUT, there would be no fuel.
I prefer the "u" in honour as it seems to be missing these days.
it was never incorporated into a tug. It has always been part of sats. With this approach, you will have a sat that can plug into a tug. The tug can be chemical, electric, or nuke (or combinations thereof). By separating the engine/fuel from the payload, it will mean that all we have to do is put something into LEO and then use a tug to move items around. A cargo load or a sat, can be done via electric. A human load, might get chemical to move up and around quickly.
I prefer the "u" in honour as it seems to be missing these days.
213 million six foot power strips daisy chained together...
The Fire Marshall will have an absolute conniption fit over that one.
A feeling of having made the same mistake before: Deja Foobar
This is not about creating an electric engine. It is about creating a TUG or Tractor that is electric powered. With such a device, it would be cheap to put a load into GEO or to EML1 cheaply.
I prefer the "u" in honour as it seems to be missing these days.
Yeah. Dawn's ion engines (linked to in TFS) have a very high ISP (3100s), but an equally low thrust (90 mN).
As a comparison, the F-1 engines on the Saturn V Stage I-C had pretty low ISP (about 250s), but a massive 34 MN of thrust.
Basically you can have high ISP (electrical) or high thrust (chemical), but not both.
Unless you go VASIMR, of course, and we're not quite there yet.
"Total destruction the only solution" - Bob Marley
We are going to get shiny metallic space suits next.
Robots that flails its arms screaming "Danger Will Robinson Danger !"
This is great stuff we are back to ION propulsion which is kind of cool. Remember the spaceships that sail like Solar wind and stuff?
That would be cool too. Perhaps next we can actually get someone to care and fund this stuff and some of it will end up actually mattering in the long run.
Of all the things in your posting, the last sentence is by far the least-likely. :(
Electric engines would either use solar panels or RTG for power, not batteries. Hell, they'd use fuel cells before they used batteries. any of these options are much much lighter than normal fuel, but even if they were equal for certain sized payloads, electric engines are much more efficient, so as payload mass increases, fuel mass scales at a much smaller rate.
Yes, but knowing our government they'd buy them all from Belkin. Then we'd still have the iconic imagery of a trail of flame following the rocket up.
Random Thoughts From A Diseased Mind (Not For Dummies)