Ion drives do work, very slowly, and with a lot of power to accomplish much thrust. Being fresh out of school, they covered some of this in my nuclear propulsion class, and it was presented as pretty much ineffective for any kind of short-term flights. It was also presented as requiring so much electric power that a nuclear reactor was essential (hence the nuke class). The beauty of the ion-propulsion system was that it operated at a low level of acceleration, but with a nuclear energy generator it could be operated for long periods of time with a relatively small amount of fuel, and would eventually result in high velocities when sufficiently distanced from gravitational fields. I'm no expert, but I doubt that a near-earth craft would get much use from ion drives. I'm utterly amazed that they use electric propulsion for this, and would like to hear more about what they're using if you could remember more? Fascinated, Robert B. -------------------------------------------- Robert B. email: robertb@nerdulator.net www.christmascheese.com - Great holiday gifts! ----- Original Message ----- From: "James Newton, Host" To: "'Microcontroller discussion list - Public.'" Sent: Thursday, December 09, 2004 8:25 PM Subject: RE: [OT] Yet another space program > > -----Original Message----- > > From: piclist-bounces@mit.edu > > [mailto:piclist-bounces@mit.edu] On Behalf Of Russell McMahon > > Sent: 2004 Dec 09, Thu 16:20 > > To: Microcontroller discussion list - Public. > > Subject: Re: [OT] Yet another space program > > > > > What may be meant is that they can get to altitudes where > > aerodynamic losses for a rocket launched into orbit are very > > very small compared to a ground launch. > > > They make mention of an "electric" drive for the last parts of the acent > into orbit. Do I remember an Ion drive or some other such thing that worked, > but only very slowly? > > --- > James Newton: PICList webmaster/Admin > mailto:jamesnewton@piclist.com 1-619-652-0593 phone > http://www.piclist.com/member/JMN-EFP-786 > PIC/PICList FAQ: http://www.piclist.com > > > > _______________________________________________ > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > > _______________________________________________ http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist