fitsmgmt.airmass.airmass_obs

fitsmgmt.airmass.airmass_obs(
    targetcoord,
    obscoord,
    ut,
    exptime,
    scale=750.0,
    full=False,
    in_deg=True,
)

Calculate effective airmass during an exposure.

Parameters

targetcoord : ~astropy.coordinates.SkyCoord: The target’s coordinate.
obscoord : ~astropy.coordinates.EarthLocation: The observer’s location.
ut : str or ~astropy.time.Time: The time when the exposure is started.
exptime : float or ~astropy.units.Quantity: The exposure time.
scale : float = 750.0: Earth radius divided by the atmospheric height (usually scale height) of the atmosphere. In IRAF documentation, it is mistakenly written that this scale is the “scale height”. Default: 750.0.
full : bool = False: If True, return the effective airmass and the start/mid/end trace. Default: False.
in_deg : bool = True: If True, store alt/az trace values in degrees. Otherwise, store strings with ":" separators. Default: True.

Wiki:

https://en.wikipedia.org/wiki/Air_mass_(astronomy)#Nonrefracting_radially_symmetrical_atmosphere

Identical to the airmass calculation for a given observational run of IRAF’s asutil.setairmass:

http://stsdas.stsci.edu/cgi-bin/gethelp.cgi?setairmass

Partly contributed by Geonwoo Kang (Seoul National University) in Apr 2018.