Algorithms from Practical Astronomy with your Calculator or Spreadsheet by Peter Duffett-Smith, implemented in Python 3. API documentation is published here.
If you're interested in this topic, please buy the book! It provides far more detail and context.
Install:
pip install practical-astronomy
Create easter.py
:
import practical_astronomy.pa_datetime as pd
print(pd.get_date_of_easter(2024))
Run it:
python easter.py
Result:
(3, 31, 2024)
If you clone the repo locally, you can run unit tests with the Make utility:
make all-tests
Documentation here.
Type | Description |
---|---|
Calculate | Date of Easter |
Convert | Civil Date to Day Number |
Convert | Greenwich Date <-> Julian Date |
Convert | Julian Date to Day-of-Week |
Extract | Day, Month, and Year parts of Julian Date |
Convert | Civil Time <-> Decimal Hours |
Extract | Hour, Minutes, and Seconds parts of Decimal Hours |
Convert | Local Civil Time <-> Universal Time |
Convert | Universal Time <-> Greenwich Sidereal Time |
Convert | Greenwich Sidereal Time <-> Local Sidereal Time |
Type | Description |
---|---|
Convert | Angle <-> Decimal Degrees |
Convert | Right Ascension <-> Hour Angle |
Convert | Equatorial Coordinates <-> Horizon Coordinates |
Calculate | Obliquity of the Ecliptic |
Convert | Ecliptic Coordinates <-> Equatorial Coordinates |
Convert | Equatorial Coordinates <-> Galactic Coordinates |
Calculate | Angle between two objects |
Calculate | Rising and Setting times for an object |
Calculate | Precession (corrected coordinates between two epochs) |
Calculate | Nutation (in ecliptic longitude and obliquity) for a Greenwich date |
Calculate | Effects of aberration for ecliptic coordinates |
Calculate | RA and Declination values, corrected for atmospheric refraction and geocentric parallax |
Calculate | Heliographic coordinates |
Calculate | Carrington rotation number |
Calculate | Selenographic (lunar) coordinates (sub-Earth and sub-Solar) |
Type | Description |
---|---|
Calculate | Approximate and precise positions of the Sun |
Calculate | Sun's distance and angular size |
Calculate | Local sunrise and sunset |
Calculate | Morning and evening twilight |
Calculate | Equation of time |
Calculate | Solar elongation |
Type | Description |
---|---|
Calculate | Approximate and precise position of planet |
Calculate | Visual aspects of planet (distance, angular diameter, phase, light time, position angle of bright limb, and apparent magnitude) |
Calculate | Position of comet (elliptical and parabolic) |
Calculate | Binary star orbit data |
Type | Description |
---|---|
Calculate | Approximate and precise position of Moon |
Calculate | Moon phase and position angle of bright limb |
Calculate | Times of new Moon and full Moon |
Calculate | Moon's distance, angular diameter, and horizontal parallax |
Calculate | Local moonrise and moonset |
Type | Description |
---|---|
Calculate | Lunar eclipse occurrence and circumstances |
Calculate | Solar eclipse occurrence and circumstances |