across.tools.visibility.constraints.airmass

Classes

AirmassConstraint

Constraint based on airmass (zenith angle) for ground-based telescopes.

Module Contents

class AirmassConstraint(/, **data)

Bases: across.tools.visibility.constraints.base.ConstraintABC

Constraint based on airmass (zenith angle) for ground-based telescopes.

Airmass affects the quality of astronomical observations. Higher airmass means more atmospheric absorption and poorer image quality. This constraint ensures observations are conducted at acceptable airmass values.

Parameters:

max_air_mass (float) – Maximum allowed airmass. Observations with higher airmass will be constrained. Typical values: 1.5-2.0 for good quality, up to 3.0 for some surveys.

__call__(time, ephemeris, coordinate)

Checks if the airmass is too high for the given coordinate and time.

name: Literal[across.tools.core.enums.ConstraintType.AIRMASS]

short_name: Literal['Airmass'] = 'Airmass'

max_air_mass: float = None

__call__(time, ephemeris, coordinate)

Check if the airmass is too high for observation.

Parameters:

• time (Time) – The time of observation.

• ephemeris (Ephemeris) – The ephemeris (used to get Earth location).

• coordinate (SkyCoord) – The coordinate to check.

Returns:

Boolean array where True indicates the airmass is too high (constraint violated).

Return type:

npt.NDArray[np.bool_]