ASTROPHYSICAL CALCULATOR
1) Distance conversion. LY, pc, AU, meters, [miles].
2) Polytropic Stars, 
   n=3, gamma=4/3, P = P_gas + P_radiation. 
   n=1.5, gamma=5/3, (Condensing[Hayashi]), or P=P_gas,
   with nuclear luminosity and core depletion.
3) Mass-Luminosity Law: M(L) or L(M).
4) m_vis from L and distance.
5) L from m_vis and distance.
6) Surface Temp(R,L(M)), or Temp(R,M), -> spectral type.
7) Spectral type -> T_surface.
8) Mixture of the elements, XYZ, and molecular weight.
9) Mixture of the elements 1 < Z < 30 and molecular wt.
10) White Dwarfs: M(R) and R(M), after theory & experiment.
11) Properties of giants and supergiants.
12) Properties of main sequence stars.
13) Nearest stars.
14) Brightest stars.
15) Compute partial opacities for viewable chemistry & ro.
16) Compute neutrino radiation L_neutrino for a star.
17) Scientific calculator, trig, log, exp, x**N, ect.
18) Bolometric corrections from angle measurements.
19) Bolometric correction as a function of T_surface.
20) Return.
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