A telescope system comprising - an entrance aperture (A1) for allowing light to pass into the telescope system at an entrance side (E1) of the telescope system ; - an exit aperture (A2) for allowing the light pass out of the telescope system at an exit side (E2) of the telescope system ; - optical components (M1-M7) configured to shape and guide the light along an optical path (L1-L8) inside the telescope system between and through the respective entrance and exit apertures (A1,A2), wherein a first part of the optical path (L1-L5) is determined by a first subset of the optical components (M1-M4) forming a first telescope stage of the telescope system , wherein a second part of the optical path (L6-L8) is determined by a second subset of the optical components (M6-M7) forming a second telescope stage of the telescope system , wherein the telescope system has an aperture stop (As) determined by a minimum opening limiting light passing between and through the entrance and exit apertures (A1,A2) of the telescope system via the optical components along the optical path (L1-L8); and - a steering mirror (M5) arranged in a part of the optical path (L5-L6) between the first telescope stage and the second telescope stage and configured to controllably rotate over a rotation angle (θm) for controlling a view angle (θv) of the telescope system from the entrance aperture (A1), wherein the steering mirror (M5) is disposed at an intermediate pupil (Pi) of the telescope system , at which position an image of the aperture stop (As) is formed by one or more of the optical components (M7,M6) there between; wherein the first telescope stage comprises a first set of curved mirrors (M1-M4), wherein the curved mirrors (M1,M2,M3,M4) comprise at least one convex mirror (M2) having a negative focal length (f2<0), wherein a sum of inverse focal lengths (1/f1+1/f2+1/f3+1/f4) of the curved mirrors (M1,M2,M3,M4) is zero. - an entrance aperture (A1) for allowing light to pass into the telescope system at an entrance side (E1) of the telescope system ; - an exit aperture (A2) for allowing the light pass out of the telescope system at an exit side (E2) of the telescope system ; - optical components (M1-M7) configured to shape and guide the light along an optical path (L1-L8) inside the telescope system between and through the respective entrance and exit apertures (A1,A2), wherein a first part of the optical path (L1-L5) is determined by a first subset of the optical components (M1-M4) forming a first telescope stage of the telescope system , wherein a second part of the optical path (L6-L8) is determined by a second subset of the optical components (M6-M7) forming a second telescope stage of the telescope system , wherein the telescope system has an aperture stop (As) determined by a minimum opening limiting light passing between and through the entrance and exit apertures (A1,A2) of the telescope system via the optical components along the optical path (L1-L8); and - a steering mirror (M5) arranged in a part of the optical path (L5-L6) between the first telescope stage and the second telescope stage and configured to controllably rotate over a rotation angle (θm) for controlling a view angle (θv) of the telescope system from the entrance aperture (A1), wherein the steering mirror (M5) is disposed at an intermediate pupil (Pi) of the telescope system , at which position an image of the aperture stop (As) is formed by one or more of the optical components (M7,M6) there between; <EOS>