powered?— is travelling for, how is it owered? . ., ., , ., powered? we have iron engines. you are throwing — powered? we have iron engines. you are throwing particles _ powered? we have iron engines. you are throwing particles at _ powered? we have iron engines. you are throwing particles at one - powered? we have iron engines. you are throwing particles at one side i are throwing particles at one side and it accelerates you in the other direction —— we have ion engines. it is firing particles out of one side. think about a rocket engine. the fire particles out one way and you accelerate the other way. the acceleration is about the equivalent of a couple of £1 coins in the end of a couple of £1 coins in the end of my finger. the advantage of an ion, it's a very slow burning, long duration engine. i ion, it's a very slow burning, long duration engine.— ion, it's a very slow burning, long duration engine. i don't understand, ion? how are _ duration engine. i don't understand, ion? how are they _ duration engine. i don't understand, ion? how are they created? - duration engine. i don't understand, ion? how are they created? we i duration engine. i don't understand, | ion? how are they created? we have the ion engine _ ion? how are they created? we have the ion engine that _ ion? how are they created? we have the ion engine that generates - ion? how are they created? we have the ion engine that generates the i the ion engine that generates the irons we need and we accelerate them out of the front. so as you fall towards mercury, you get faster and faster as you are heading towards the centre will be slow the spacecraft down.—