1. A nuclear medicine camera having an X-ray imaging capability, comprising: a gantry having a stationary portion and at least one rotating portion; at least one gamma camera mounted on a said at least one rotating portion and capable of being rotated together at a common first rotation rate about an axis, said at least one gamma camera being capable of acquiring nuclear imaging data for reconstructing a tomographic nuclear image; and an X-ray CT imager having an X-ray source mounted on said at least one rotating portion and being capable of acquiring X-ray imaging data for reconstructing an X-ray image; said X-ray CT imager being mounted closer to said stationary portion than said at least one gamma camera.