New Ion Engine Being Tested

Dr Cool writes "A new design of spacecraft ion engine has been tested by the European Space Agency which dramatically improves performance over present thrusters and marks a major step forward in space propulsion capability. Ion engines are a form of electric propulsion and work by accelerating a beam of positively charged particles (or ions) away from the spacecraft using an electric field. 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."

Comments

cool but

[ShaneThePain]

Ion engines are high impulse, low torque, so they are appropriate only once your already IN space. even then, there is extremely slow acceleration. I think the construction of a space elevator http://en.wikipedia.org/wiki/Space_Elevator would be a much greater step towards "casual" space flight. even so, very cool.

Deep Space 1

[saskboy]

I remember reading about Deep Space 1 and it's Ion engine about 8 years ago. I was most impressed that the thrust is about that felt on your hand by a piece of paper when held on Earth. The key is that it accelerates the ship to a speed much greater than traditional rockets, not how quickly it does that. Besides, you don't want to go from 0 to 60 in .058 seconds, unless you want to be a smear on the bulkhead.

Increase in the number of grids

[Verloc]

This innovation came from the addition of another grid (from TFA) used in the process of accelerating the ions. Is there any reason that they couldn't just keep adding grids with varying voltages? And why are the last two voltages both low? Wouldn't it make sense to alternate them?

Not so dumb.

[imsabbel]

Well... on earth, nothing would happen, as this kind of engine only works in vaccuum... The mean free travel lenght of those ions in air would be meassured in mircrometers...

In vaccuum, you would die rather violently, due to shortage of air....

So i dont think this is a practical concern...

Of course, if you were in a spacesuit, there would be an issue...

The process (hitting an object with high energy noble gas ions) is also used on earth, where to precess is used to alter surfaces of materials. Its called "sputtering", or "plasma etching". So i guess you can get a general idea of what it does... It cant penetrate your spacesuit, but will happily kick layer by layer of atoms from its surface.

If you waited long enough, it would open holes/ect, but it you be very damaging to sensor equipment/solar cells even with short exposures.

Think of a very low power slaver desintegrator from the ringworld novels :D

Re:Don't go getting any ideas

[Anonymous Coward]

"ButFTL acceleration is not impossible. It is completely meaningless as it simply violates causality. If FTL accn is possible, then our entire understanding of physics is almost completely wrong, and there is ample tangible evidence to suggest that is not so."

I wouldn't say that. What about Quatum tunneling?

http://www.npl.washington.edu/AV/altvw75.html

"In particular, Aichmann and Nimtz have recently transmitted Mozart's 40th Symphony as frequency modulated microwaves through an 11.4 cm length of barrier wave guide at an FTL group velocity of 4.7 c, receiving audibly recognizable music from the microwave photons that survived their barrier passage. The transit time through the barrier was about 81 picoseconds and was observed to be constant for barriers with widths varying from 4.0 cm to 11.4 cm."