This site provides an interface to Goddard's Planetary Spectrum Generator (PSG), which can be used to generate high-resolution spectra of planetary bodies (e.g., planets, moons, comets, exoplanets). The spectroscopic suite can be also accessed remotely via the Application Program Interface (API). When requiring help on a specific input parameter, please click on the Help icon.

Calculation template Help
Target and geometry HelpTarget: C/2007 W1 for date (2008/07/09 15:10 UT); geometry: Observatory from 0.3484 AU.
Atmosphere and surface HelpProduction rate: 8.1900e+27 molecules/sec; Expansion velocity: 846.67 m/s; Atmospheric temperature: 81.5102 K; Gases: CH4,C2H6,CH3OH; Surface temperature: 200.0000 K; Albedo: 0.0400; Emissivity: 0.9600;
Instrument parameters HelpWavelength range 2959.311375-3006.935775 cm with a resolution of 25000.000000 RP. Molecular radiative-transfer enabled; Continuum flux module enabled;


Instrument parameters

Telescope / instrument Help  
telescope NIRSPEC is the Near Infrared Spectrometer at the Keck observatory on Manuakea (4200m), Hawaii. It is a cryogenic cross-dispersed echelle spectrograph which features spectroscopy over the 0.96-5.5 micron range at resolutions up to 40,000 (although currently optimized for RP lower than 25,000). The instrument samples this broad spectral range by employing an array of cross-dispersers and filter configurations.
Frequency/wavelength range:    Resolution:
Include atmospheric signatures Help      Include continuum fluxes     Integrate stellar templates
Terrestrial transmittance Help  Apply    Multiply   Altitude/Water:
Radiation units: Help    Log plot
Telescope Help Beam [FWHM]:     Exozodi level:
Diameter [m, effective]:    Telescopes:  
Noise Help Time / exposure [s]:   Number of exposures:   Number of pixels:
NETD[mK]:   Speed[Hz]:   ηTotal, εopt, Topt[K]