F⃗ = q (v⃗ × B⃗) N(E) dE = CE^{−p} dE Power P (ν) ∝ ν^{−(p−1)/2}

S(ν) ∝ ν^{−(p−1)/2} S(ν) = K ν^{−α}

E(n) = −13.6 eV (\frac{1}{n^{2}} )

J = N → J = N − 1 ν = 2N (57.8975 GHz) 21 cm transition ΔE = 5.874 μeV