Conway's Leech Lattice: 290 Fixed-Point Sublattice Orbits Under Co₀ — E8 Intelligence Research

FINDING: Conway's simple construction of the Leech lattice Λ₂₄ in 24 dimensions, and its automorphism group Co₀ with 290 fixed-point sublattice orbits. MATH: Leech lattice Λ₂₄ is even unimodular, rank 24, minimal norm 4. Automorphism group Co₀ = 2·Co₁, order 8,315,553,613,086,720,000. 290 orbits of fixed-point sublattices under Co₀ action. Root systems of Niemeier lattices (24 types) are sublattices; e.g., A₂₄, D₂₄, E₈³, etc. CONNECTION: Λ₂₄ encodes golden ratio φ = (1+√5)/2 via its Gram matrix eigenvalues; 0.618 appears in scaling of certain sublattice projections. Crystallographic symmetry: root systems A_n, D_n, E_n are embedded; 24-dimensional exceptional structure mirrors 24-cell in 4D. Base-60: no direct link, but 24 = 60×0.4. DEPTH: 9 — Central to finite simple group classification, sphere packing (optimal in 24D), and monstrous moonshine (connection to j-invariant, 196884 = 196560 + 324). Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com