a method and an apparatus for locating in the sky celestial objects , using a telescope , wherein two guide stars and the celestial object are represented , according to their respective locations , on a disc which is able to rotate with respect to the telescope around an axis , orthogonal to the telescope axis , and passing through the representation of the celestial objects . the images of the two guide stars are projected in the sky and the telescope and the disc are moved until the images of the guide stars are superposed with the respective actual guide stars in the sky . the guide stars form a triangle with the celestial object . the telescope is preferably provided with a alt - azimuth type mounting . the guide stars are represented on the disc by small holes . a light source placed under the disc creates light dots which are projected in the sky using a plano convex lens optically aligned with the disc rotation axis , and a semi - transparent mirror inclined at 45 degrees on the rotation axis .