Question about Ion engines

[grooble]

I know they are really slow and take time to build up speed. So what if you strapped a small rocket on, just to get a decent start on the acceleration, and then kicked in the ion drive after?<br /><br />Would that make it better?

 

[henryhallam]

That's usually what's done, at least in the limiting case of using an ordinary rocket to get it to at least LEO. SMART-1 was launched from geostationary transfer orbit i.e. ~650km x 36000km and even then it took 16 months to reach the moon. The ion engines were pretty small though.<br />Deep Space One rode a Delta II to Earth escape velocity and that meant it could reach its first flyby target, the asteroid 1992 KD, in only 10 months. The DS1 mission exceeded all expectations and is well worth reading about, a fantastic machine.

 

[Testing]

Quick facts<br /><br />http://nmp.jpl.nasa.gov/ds1/quick_facts.html <br /><br />Solar Electric Propulsion<br /><br />http://nmp.jpl.nasa.gov/ds1/tech/sep.html <div class="Discussion_UserSignature"> </div>