[ExI] Dawn launch (loading the xenon)

[Amara Graps]

>Are these spacecrafts going to fly themselves?

Dear Anna,

There is ONE spacecraft (see the photos I posted please):
http://mediaarchive.ksc.nasa.gov/search.cfm?cat=173

Dawn:
http://en.wikipedia.org/wiki/Dawn_Mission

*All spacecraft* fly themselves with an initial rocket launch to escape
Earth's gravity 'well'
http://en.wikipedia.org/wiki/Escape_velocity

and often with gravity boosts from close flybys of other planets,
http://en.wikipedia.org/wiki/Gravitational_slingshot

and with the spacecraft's own propulsion. This spacecraft will arrive at
its first asteroid (Vesta) in the Asteroid Belt in 2011, so the xenon is
part of Dawn's propulsion system. The xenon provides the 'fuel' for Dawn's
ion drive; a new technology for NASA, having only been used on NASA's
DS-1 before. But ESA's SMART-1 and JAXA's Hayabusa missions have
demonstrated more the ion drive's successes.

Ion Drives
http://en.wikipedia.org/wiki/Ion_thruster
http://nmp.nasa.gov/ds1/tech/ionpropfaq.html
http://www.esa.int/SPECIALS/SMART-1/SEMLB6XO4HD_0.html

-- 

Amara Graps, PhD      www.amara.com
Associate Research Scientist, Planetary Science Institute (PSI), Tucson
INAF Istituto di Fisica dello Spazio Interplanetario (IFSI), Roma, Italia