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Interactive study: the computer history timeline (abacus to AI, pan and zoom), 3D printing (an introduction to printers and plastics), a power-supply multimeter test (colored plugs only; never open the case), maths lessons (trig, linear algebra, calculus), the Standard Model particle grid (quarks, leptons, bosons, three forces), and the sibling Gravity desk (weight, Newton, Einstein — the force SM omits). Maps: solar system, Moon phases, seasons (axial tilt, not distance), twilight (sunrise, sunset, and the three twilights, from NOAA’s solar calculator), airmass (Kasten and Young relative air mass, k times airmass of extinction, and Bennett’s about 34′ at the horizon), the analemma (the noon Sun’s figure-8 — tilt plus the equation of time), the sidereal day (one spin against the stars is shorter than the mean solar day), the synodic month (new Moon to new Moon is longer than one orbit), libration (the same lunar face, plus a peek past the limbs), the precession of the equinoxes (the pole star changes; the tropical year is shorter than the sidereal year), Kepler’s third law (P² = a³ in years and AU), escape and orbital speed (a circular orbit and escape, √2 apart), a Hohmann transfer (the half-ellipse between two circular orbits; Earth to Mars is 258.88 days), Earth satellite orbits (period, speed, ground track, horizon, and light time; the cited 420 km circle is 92.97 min and geostationary is 35,786.05 km), the five Lagrange points (L1 through L5; Sun–Earth L2 is 1,501,538 km from Earth), the Roche limit (a fluid distance and a rigid one; Rhea and the Moon outside, Phobos between), the Hill sphere (where a secondary dominates; Earth’s is 1,496,565 km and the Moon sits inside it), the angular size of the Moon and the Sun (δ = 2·arctan(d / 2D); a mean-perigee Moon is 32.880′ and can cover the Sun), telescope optics (focal ratio, magnification, exit pupil, Rayleigh’s 1.22 λ/D, and Dawes’s 116/D), stars types & lives, stellar magnitude (apparent m, absolute M, five magnitudes is a factor of 100), meteor showers (observed hourly rate from ZHR, radiant altitude, limiting magnitude, and population index; the IMO row at 30° is 50), asteroid and comet impacts (mass, megatons, and Collins et al. 2005 crater diameters; not a hazard assessment), an HR diagram (effective temperature versus luminosity, hot on the left), stellar lifetime (mass, an approximate luminosity, and a 10 Gyr × M/L scaling), black holes (Schwarzschild radius, photon sphere, and ISCO; the nominal solar mass is 2.953 km), redshift (z = (λ_obs − λ_rest)/λ_rest; at z = 1, relativistic β = 0.6), a distance ladder (modulus with extinction, Cepheids, Type Ia, and cz/H0), a cosmology calculator (age, lookback time, and the cosmological distances), exoplanets (orbits, sizes, plain-English planet cards), a transit and radial-velocity calculator (depth, duration, and K), a habitable zone (stellar flux, equilibrium temperature, and the Kopparapu et al. 2014 limits), Earth’s atmosphere layers, and light pollution literacy — including Day for Night on Salesforce Tower — plus the electromagnetic spectrum (radio to gamma, Wien’s peak), ore mining & lithium, the ice crop, and ocean metals, plus hemispheric waves, and the nested humanoid robotics status essay. Educational schematics — not precision models.