really sounds like star trek

[tocqueville]

Preparing for Ion Drive Firing
22 Jul 2005 11:36

Overall Status

During the period 20 June to 17 July 2005, SMART-1 ground activities focused on planning and preparing for the upcoming firing of the ion drive.

It is planned to exhaust all the Xenon available in the tank going beyond the design limit of 2 kg. This has required special simulations and the development of new procedures.

http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=37703

http://www.esa.int/SPECIALS/SMART-1/

__________________________________________________________________
Europe's Ariane-5 launcher will put SMART-1 into orbit
Its main purpose is to let engineers evaluate a new way of propelling spacecraft, on far-ranging space missions. Power from SMART-1's solar panels will drive an electric propulsion system called an 'ion engine'.

[Beaver Tail]

1. Remember this from Star Trek?

The Hypospray?
The Plastic Cartridge you stuck in the computer? It contained Information
The Silver platter that strored historial Records and was read by a laser?

Hmmmmmm

Gene ahead of his time

[MrMonk]

2. Did you notice that the ship's computer system

included networked work stations?

[Tesha]

14. You forgot the communicator...

You forgot the communicator, a device that is directly credited with
inspiring Motorola's early "flip phone" cell phone designs.

And a weapon not too unlike a phaser is now in development (although
at the moment, it only ranges up to "stun" and doesn't vaporize anything
yet).

Tesha

[iconoclastic cat]

3. I read the "fact sheet," but I still don't understand how it works.

It looks like it packs a lot of thrust in that engine, though!

[tocqueville]

4. explanation

The first technology to be demonstrated on SMART-1 will be Solar Electric Primary Propulsion (SEPP), a highly efficient and lightweight propulsion system that is ideal for long-duration deep space missions in and beyond our solar system. SMART-1's propulsion system consists in a single ion engine fuelled by 82 kg of xenon gas and pure solar energy. This plasma thruster relies on the Hall effect" to accelerate xenon ions to speed up to 16,000 km/hour. It is able to deliver 70 mN of thrust with a specific impulse (the ratio between thrust and propellant consumption) 5 to 10 times better than traditional chemical thrusters and for much longer durations (months or even years, compared to the few minutes' operating times typical of traditional chemical engines).

[iconoclastic cat]

5. Does it have to be out of Earth's atmosphere to work?

Also, does it create any sort of hazardous waste?

[tocqueville]

6. yes and no

it would be a very slow start so using other means of propulsion is more efficient to day to reach orbit. The idea is to have a constant accelaration for long-distance with small amounts of fuel. In theory a bigger engine like that could accelarate to the near speed of light.

Xenon is an inert gas. Accelerated xenon ions would be only a fart in the cosmic backgtround radiation. Since the power to ignite the reaction is provided by solar cells, no fissile fuels like plutonium are needed.

[iconoclastic cat]

8. Could a spacecraft really go the speed of light without coming apart?

Besides, if it were to hit even the smallest rock going that fast, wouldn't it explode?

[tocqueville]

9. doesn't have to go that fast

you could destroy the space station with a tiny rock...

and about coming apart I think it has to do with the construction... but it's another story...

and space is mostly "empty"

[phantom power]

11. it works like this...

you can approach the speed of light as closely as you want, but you will never reach it. As you continue to spend energy accelerating, more and more of that energy becomes relativistic mass, while your actual speed flattens out just under the speed of light.

As you approach the speed of light, any particles you run into begin to resemble high-energy radiation. So you would need an ionizing-laser and powerful magnetic fields to turn everything ahead of you into charged particles, and then deflect those particles with the magnet.

And make sure you don't run into anything too large for your laser to ionize :-)

[Tesha]

15. That was why the Enterprise had a "main deflector array" facing forward.

Even impinging hydrogen atoms/molecules are nasty near the speed of light.

Tesha

[phantom power]

7. It's far too weak to be used in an atmosphere.

It works well in space, because low thrust over a long time adds up nicely. These ion-engines are very high efficiency, but are very low in power. In other words, not at all like star-trek :-)

If you did burn it on earth, I don't think the waste would be toxic. And there wouldn't be much of it, if it was.

[tocqueville]

10. yep but enterprise had a warp drive...

I just tought that "Preparing for Ion Drive Firing" sounded so Star Trek like


remember that SMART-1 is just a model. ESA is planning a much bigger one depending of the results of the SMART-mission...

[phantom power]

12. true, the next generation of engines will be exciting.

But all the designs I've seen are still low-power, compared to chemical rockets. I suppose they're limited more by the mass of the electic power supply than anything else.

[Ian David]

16. An ion drive with the power of a sportscar can deflect a large asteroid

Given 20-30 years of sitting on the rock.

I forget where I read that.

[rman]

13. Old news; 1st ion drive operational in 2000

Deep Space 1 sets record with ion propulsion system
By Paul Hoversten
Washington Bureau Chief
posted: 07:00 am ET
17 August 2000
http://www.space.com/scienceastronomy/solarsystem/deepspace_propulsion_000816.html

Still quite neat though.