Have an interesting (and hopefully easy) question for you. Does the Shuttle require the Earth (and any resulting force/element) for Launch? Such as, Atmosphere. Does the main engines, or SRB's utilize the atmosphere to aid in the ignition or combustion? Does the Shuttle utilize the magnetic pull of the Earth, the rotational velocity, anything? My 'research' suggests that the atmosphere may be required for the SRB ignition. So, the small rocket motor... is its reaction self contained, or does it use the elements (O2?) in the atmosphere to generate the 'Flames'? Do you think the SRB's could ignite and be used in space? If not, then the shuttle does use the Earth (ok, the atmosphere) to launch.. Input?