Calculate the airmass¶
Plane-parallel atmosphere¶
- PyAstronomy.pyasl.airmassPP(zangle)¶
Calculate airmass for plane parallel atmosphere.
- Parameters
- zanglefloat or array
The zenith angle in degrees.
- Returns
- Airmassfloat or array
The airmass assuming a plane parallel atmosphere.
Example: Airmass with plane-parallel atmosphere¶
from __future__ import print_function, division
from PyAstronomy import pyasl
print("Airmass for plane-parallel atmosphere")
for za in range(0,70,10):
print("Zenith angle: %2d deg, airmass = %7.2f" % \
(za, pyasl.airmassPP(za)))
Airmass for spherical, homogeneous atmosphere¶
- PyAstronomy.pyasl.airmassSpherical(zangle, obsAltitude, rearth=6371.0, yatm=10.0)¶
Calculate the airmass for a given zenith angle and observer altitude.
This routine uses a geometric formula for a homogeneous, spherical atmosphere with an elevated observer.
Note
In this model, the airmass is not necessarily one toward the zenith.
- Parameters
- zanglefloat, array
Zenith angle of an object in deg.
- obsAltitudefloat
Elevation of the observer in meter.
- rearthfloat, optional
Earth’s radius in km.
- yatmfloat, optional
Height of the atmosphere in km.
- Returns
- Airmassfloat or array
The airmass.
Example: Airmass with homogeneous, spherical atmosphere¶
from __future__ import print_function, division
from PyAstronomy import pyasl
obsAlt = 2400.0
for za in range(0,90,10):
print("Zenith angle: %2d, airmass = %7.2f" % \
(za, pyasl.airmassSpherical(za, obsAlt)))
