airmass(1) --- Imcat Users Guide --- section: imcattools_orbits --- last changed: Sun Apr 13 HST
airmass - compute minimum air-mass for observation of a targetSYNOPSIS
airmass lon lat min_zd_solar min_zd_lunar dphase nstepsDESCRIPTION
airmass computes, as a function of time, the minimum angle from zenith and airmass for a target at helio-ecliptic coords lon lat when the solar angle from zenith is at least min_zd_solar degrees and the lunar angle from the zenith is at least min_zd_lunar degrees.
The phase increment dphase is given in degrees relative to winter. We output the time (relative to midnight in hours) and the and minimum zenith distance and air-mass of the target. If nsteps is negative, then we output the results for a single time = -nsteps * dphase. AUTHOR
Nick Kaiser --- kaiser@hawaii.edu