An all-reflective optical system (100, 150, 170, 190, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1430, 1460, 1480), comprising: a concave primary mirror (104, 154, 174, 194, 204, 304, 404, 504, 604, 704, 804, 904, 1004, 1104, 1204, 1304, 1404, 1434, 1464) having a central aperture (212, 310) and a radius, the primary mirror having one of a parabolic, non-parabolic conical, or aspherical surface; a convex secondary mirror (105, 155, 175, 195, 205, 305, 405, 505, 605, 705, 805, 905, 1005, 1105, 1205, 1305, 1405, 1435, 1465) facing the primary mirror, the secondary mirror having an aspherical surface, wherein an optical axis extends from a vertex of the primary mirror to a vertex of the secondary mirror; a concave tertiary mirror (113, 163, 173, 193, 213, 313, 413, 513, 613, 713, 813, 913, 1013, 1113, 1213, 1313) arranged behind the primary mirror, the tertiary mirror having one of a parabolic, non-parabolic conical, or aspherical surface; a concave quaternary mirror (114, 164, 184, 198, 214, 314, 414, 514, 614, 714, 814, 914, 1014, 1114, 1214, 1314) arranged in the central aperture of the primary mirror or behind the primary mirror, the quaternary mirror having one of a spherical, parabolic, non-parabolic conical, or aspherical surface; and at least one image plane (118, 168, 316, 416, 516, 616, 716, 816, 916, 1016, 1116, 1216, 1316) having one or more aggregated sensors, wherein the image plane (118, 168, 189, 199, 316, 416, 516, 616, 716, 816, 916, 1016, 1116, 1216, 1316) is positioned at a radial distance from the optical axis that is no more than the radius of the primary mirror, characterized by a form factor, defined as a ratio of a distance between the secondary mirror and the tertiary mirror to an effective focal length of the optical system, is less than 0.09. a concave primary mirror (104, 154, 174, 194, 204, 304, 404, 504, 604, 704, 804, 904, 1004, 1104, 1204, 1304, 1404, 1434, 1464) having a central aperture (212, 310) and a radius, the primary mirror having one of a parabolic, non-parabolic conical, or aspherical surface; a convex secondary mirror (105, 155, 175, 195, 205, 305, 405, 505, 605, 705, 805, 905, 1005, 1105, 1205, 1305, 1405, 1435, 1465) facing the primary mirror, the secondary mirror having an aspherical surface, wherein an optical axis extends from a vertex of the primary mirror to a vertex of the secondary mirror; a concave tertiary mirror (113, 163, 173, 193, 213, 313, 413, 513, 613, 713, 813, 913, 1013, 1113, 1213, 1313) arranged behind the primary mirror, the tertiary mirror having one of a parabolic, non-parabolic conical, or aspherical surface; a concave quaternary mirror (114, 164, 184, 198, 214, 314, 414, 514, 614, 714, 814, 914, 1014, 1114, 1214, 1314) arranged in the central aperture of the primary mirror or behind the primary mirror, the quaternary mirror having one of a spherical, parabolic, non-parabolic conical, or aspherical surface; and at least one image plane (118, 168, 316, 416, 516, 616, 716, 816, 916, 1016, 1116, 1216, 1316) having one or more aggregated sensors, wherein the image plane (118, 168, 189, 199, 316, 416, 516, 616, 716, 816, 916, 1016, 1116, 1216, 1316) is positioned at a radial distance from the optical axis that is no more than the radius of the primary mirror, characterized by a form factor, defined as a ratio of a distance between the secondary mirror and the tertiary mirror to an effective focal length of the optical system, is less than 0.09.