Space Propulsion Breakthrough

[FLO]

11 January 2006

The European Space Agency and the Australian National University have successfully tested a new design of spacecraft ion engine that dramatically improves performance over present thrusters and marks a major step forward in space propulsion capability. 

ESA is currently using electric propulsion on its Moon mission, SMART-1. The new engine is over ten times more fuel efficient than the one used on SMART-1. “Using a similar amount of propellant as SMART-1, with the right power supply, a future spacecraft using our new engine design wouldn’t just reach the Moon, it would be able to leave the Solar System entirely,” says Dr Roger Walker of ESA’s Advanced Concepts Team, Research Fellow in Advanced Propulsion and Technical Manager of the project.

http://tinyurl.com/8webz

[The Warthog]

How's that for fast work? I first heard of ion engines when I was in elementary school. It looks as though by the time I'm dead, I'll be seeing them in use! Progress!

[daz]

What a great result!!

Pity they can't do the same to the petrol engine!

[The Warthog]

They can, but the oil companies are buying up all the patents for efficient fossil fuel engines, and refusing to develop them.

[daz]

I figured as much.

>soap-box<

Good to know that the richest people on the planet are stifling the advancements in technology that would allow EVERYONE to enjoy Mother Nature's harvest.

>/soap-box<

[The Warthog]

Actually, I was just light-heartedly repeating an oft-repeated urban legend about fuel efficient engines, Hence the wink at the end of m post. I doubt that it's true.

[daz]

I'm more of a cynic WH!!!

[Greg]

very interesting form of propulsion, found some info....

Ion propulsion is a technology that involves ionizing a gas to propel a craft. Instead of a spacecraft being propelled with standard chemicals, the gas xenon (which is like neon or helium, but heavier) is given an electrical charge, or ionized. It is then electrically accelerated to a speed of about 30 km/second. When xenon ions are emitted at such high speed as exhaust from a spacecraft, they push the spacecraft in the opposite direction.

Under the circumstances for which ion propulsion is appropriate, it can push a spacecraft up to about ten times as fast as chemical propulsion. Because the ion propulsion system, although highly efficient, is very gentle in its thrust, it cannot be used for any application in which a rapid acceleration is required. With patience, the ion propulsion system on DS1 imparts about 3.6 km/s to the spacecraft. To undertake the same mission with a chemical propulsion system would require a more expensive launch vehicle and a larger spacecraft to accommodate a large tank for the chemical propellants.

Ion propulsion could be used for a manned mission to Mars. The decision on whether that would be the preferred approach would involve many questions such as which technique might get the crew there the fastest (independent of how fuel efficient the trip might be) in order to reduce the radiation exposure and effects of long periods of near weightlessness.

The ultimate speed of a spacecraft using ion thrust depends upon how much propellant it carries; indeed, the same principle applies to chemical propulsion systems, although they are much less efficient. The ion propulsion system on Deep Space 1 carries about 81.5 kilograms of xenon propellant, and it takes about 20 months of thrusting to use it all. It increases the speed of the spacecraft by about 4.5 kilometers per second, or about 10,000 miles per hour. If we had the same amount of chemical propellant, it would provide only one tenth as much velocity increment. If DS1 carried a larger solar array, it certainly would have a slightly higher acceleration, and if it carried more Xe propellant it could reach a much higher final velocity by simply thrusting longer. But DS1 is testing ion propulsion solely to find out if it works as well as predicted. Future missions that use it likely will carry more propellant to achieve still higher speeds.

Greg

[daz]

Good research Greg, thanks for that - saves me a bit of legwork

[Ant]

You'd need the same amount of propellant and time to slow down at the other end though! So half way to mars you'd need to reverse the trust and and start decelerating...

Or am I wrong?

Ant

[Greg]

We are now heading towards the "Science of Star Trek"

Ion drives !!

Trilithium!!!

Whats next Soliton Waves!!

Greg

[daz]

Good point Ant......

It's not like you can deploy an air speed brake, or chuck the anchor out.

[daz]

In fact, I've just sent them an email - I'll let you know the answer!!!

[Ambermile]

Good point Ant......

It's not like you can deploy an air speed brake, or chuck the anchor out.

Umm - actually, you can... If you aim well enough you can let the planet's gravity slow you down and drop you into orbit around it.

[Ant]

Surely it would depend how fast the craft was going wouldn't it? There must be a limit to how much speed the gravity of a planet can slew?

I'm sure that I've not exlain that too well, but you know what I mean.

Ant

[The Warthog]

Since this engine will be operating for a long time, will the acceleration it provides give the crew artificial gravity for most of the trip? At what g?

[Kaptain Klevtsov]

Presumably these ion engines could be adapted to use any old stuff for fuel so long as it could be ionised? This could mean that the trip to Mars wouldn't need to carry the fuel for the return journey, rather they would shovel in some local dust and use that to come back. If the electrical power is generated by PV arrays, then the sky is no longer the limit, rather the radius from the sun that provides enough light is.

Make any sense?

Captain Chaos