astrocalc.coords.separations

Calculate separations between sky-coordinates

Author

David Young

Module Contents

Classes

separations

The worker class for the separations module

API

class astrocalc.coords.separations.separations(log, ra1, dec1, ra2, dec2, settings=False)

Bases: object

The worker class for the separations module

Key Arguments

• log – logger

• settings – the settings dictionary

• ra1 – the right-ascension of the first location. Decimal degrees or sexegesimal.

• dec1 – the declination of the first location. Decimal degrees or sexegesimal.

• ra2 – the right-ascension of the second location. Decimal degrees or sexegesimal.

• dec2 – the declination of the second location. Decimal degrees or sexegesimal.

Usage

… todo::

- replace get_angular_separation throughout all code using dryxPython
- replace getAngularSeparationthroughout all code using dryxPython

You can input sexegesimal coordinates,

from astrocalc.coords import separations
calculator = separations(
    log=log,
    ra1="23:32:23.2324",
    dec1="-13:32:45.43553",
    ra2="23:32:34.642",
    dec2="-12:12:34.9334",
)
angularSeparation, north, east = calculator.get()
print(angularSeparation, north, east)

# OUT: '4813.39431', '4810.50214', '166.83941'

or decimal degrees,

from astrocalc.coords import separations
calculator = separations(
    log=log,
    ra1=2.3342343,
    dec1=89.23244233,
    ra2=45.343545345,
    dec2=87.3435435
)
angularSeparation, north, east = calculator.get()
print(angularSeparation, north, east)

# OUT: '7774.4375', '-6800.0358', '4625.7620'

or even a mix of both

from astrocalc.coords import separations
calculator = separations(
    log=log,
    ra1=352.5342343,
    dec1=89.23,
    ra2="23:32:34.642",
    dec2="89:12:34.9334"
)
angularSeparation, north, east = calculator.get()
print(angularSeparation, north, east)

# OUT: '78.9', '-73.1', '29.9')

Initialization

get()

Calulate the angular separation between two locations on the sky

Input precision should be respected.

Key Arguments

Return

• angularSeparation – total angular separation between coordinates (arcsec)

• north – north-south separation between coordinates (arcsec)

• east – east-west separation between coordinates (arcsec)

See main class usage for details.