A large reflector inflatable telescope. The telescope has an inflatable hull with a conical lower portion and a hemispherical upper portion. The conical portion is transparent to electromagnetic waves so that radio or light waves can reach an inner reflector, which is interposed between the conical portion and the hemispherical portion. The presence of the inner reflector allows the conical portion and the hemispherical portion to be inflated at different pressures such that the reflector becomes spherical or parabolic. If desired, the reflector can be made adjustable with a membrane behind the reflector that provides electro-static force to shape the reflector.