ChromaStar (formerly "GrayStar")

Reliably responsive in Chrome, Opera, and sometimes Edge browsers under Windows
OpenStar pedagogical star and planet modeling in JavaScript. Visualization in HTML5. Hover for tips. Ctrl +/- to zoom

Input:

Show/Hide stellar

Stellar parameters
Effective temperature, Teff
(3400 - 50000) K)
Log10 surface gravity, log(g)
(0.0 - 5.5 cm s-2 = dynes g-1)
Stellar mass
(0.1 - 20.0 MSun)
Metal content
(log10 0.001 - 10.0 x solar)
κFudge log10 mass extinction (-2.0 - 2.0 log cm2 g-1)
[He/Fe] (-1 - 1)
[C/O] (-2 - 2)
[α/Fe] (-0.5 - 0.5)

Show/Hide habitable zone

Habitable Planet Zone parameters
Surf pressure
(0.6 - 22000 kPa)
Greenhouse effect, ΔT
(-200 - +600 K)
Albedo (0.0 - 0.95)
Organic solvent
Water Methane Ammonia Carbon dioxide

Show/Hide spectral line

Show/Hide samples

Show/Hide performance/realism

Output:

Narrow band Gaussian filter λ (270 - 2550 nm) σ (0.01 - 10 nm)
Plots: Atmosphere Chem Eq (if Atmos plots ON) Radiation field 2-level atom: spectral line
Detailed print-out (below graphs): None Atmospheric structure Flux spectral energy distribution (SED) Specific intensity distribution High resolution spectral line profile Limb darkening coeffs Chem Eq (See Plot section menu)