Calculations for the position of the sun and moon.

## Astral V0.4

Astral is a python module for calculating the times of various aspects of the sun.

It calculates the following

Dawn
The time in the morning when the sun is a specific number of degrees below the horizon.
Sunrise
The time in the morning when the top of the sun breaks the horizon (asuming a location with no obscuring features.)
Solar Noon
The time when the sun is at its highest point.
Sunset
The time in the evening when the sun is about to disappear below the horizon (asuming a location with no obscuring features.)
Dusk
The time in the evening when the sun is a specific number of degrees below the horizon.
Solar Azimuth
The number of degrees clockwise from North at which the sun can be seen
Solar Elevation
The number of degrees up from the horizon at which the sun can be seen
Rahukaalam
“Rahukaalam or the period of Rahu is a certain amount of time every day that is considered inauspicious for any new venture according to Indian astrology”.
Moon Phase
Calculates the phase of the moon for a specified date.

## Example

The following example demonstrates the functionality available in the module

```import datetime
from astral import Astral

city_name = 'London'

a = Astral()
a.solar_depression = 'civil'

city = a[city_name]

print('Information for %s/%s\n' % (city_name, city.country))

timezone = city.timezone
print('Timezone: %s' % timezone)

print('Latitude: %.02f; Longitude: %.02f\n' % \
(city.latitude, city.longitude))

sun = city.sun(date=datetime.date(2009, 4, 22), local=True)
print('Dawn:    %s' % str(sun['dawn']))
print('Sunrise: %s' % str(sun['sunrise']))
print('Noon:    %s' % str(sun['noon']))
print('Sunset:  %s' % str(sun['sunset']))
print('Dusk:    %s' % str(sun['dusk']))
```

Produces the following output:

```Information for London/England

Timezone: Europe/London
Latitude: 51.60; Longitude: 0.08

Dawn:     2009-04-22 05:12:56+01:00
Sunrise:  2009-04-22 05:49:36+01:00
Noon:     2009-04-22 12:58:48+01:00
Sunset:   2009-04-22 20:09:07+01:00
Dusk:     2009-04-22 20:45:52+01:00
```

## Dependencies

Astral has one external dependency on ‘pytz’ which can either be obtained from Sourceforge page or via the easy_install method, whichever is your particular poison.

## Installation

When you’ve added the pytz package to install astral unzip the archive to a handy location and execute the standard Python installation method:

```python setup.py install
```

## Cities

The module includes location and time zone data for the following cities. The list includes all capital cities plus some from the UK. The list also includes the US state capitals and some other US cities.

### US Cities

Albany, Albuquerque, Anchorage, Annapolis, Atlanta, Augusta, Austin, Baltimore, Baton Rouge, Billings, Birmingham, Bismarck, Boise, Boston, Bridgeport, Buffalo, Burlington, Carson City, Charleston, Charlotte, Cheyenne, Chicago, Cleveland, Columbia, Columbus, Concord, Dallas, Denver, Des Moines, Detroit, Dover, Fargo, Frankfort, Harrisburg, Hartford, Helena, Honolulu, Houston, Indianapolis, Jackson, Jacksonville, Jefferson City, Juneau, Kansas City, Lansing, Las Vegas, Lincoln, Little Rock, Los Angeles, Louisville, Madison, Manchester, Memphis, Miami, Milwaukee, Minneapolis, Montgomery, Montpelier, Nashville, New Orleans, New York, Newark, Oklahoma City, Olympia, Omaha, Orlando, Philadelphia, Phoenix, Pierre, Portland, Portland, Providence, Raleigh, Richmond, Sacramento, Saint Paul, Salem, Salt Lake City, San Diego, San Francisco, Santa Fe, Seattle, Sioux Falls, Springfield, Tallahassee, Toledo, Topeka, Trenton, Virginia Beach, Wichita, Wilmington

## Thanks

The sun calculations in this module were adapted, for Python, from the following spreadsheet.

http://www.ecy.wa.gov/programs/eap/models/twilight.zip

Which takes its calculations from

http://www.srrb.noaa.gov/highlights/sunrise/azel.html

The moon phase calculation is based on some javascript code from Sky and Telescope magazine

Moon-phase calculation
Roger W. Sinnott, Sky & Telescope, June 16, 2006.

Also to Sphinx for making doc generation an easy thing (not that the writing of the docs is any easier.)

## Contact

Simon Kennedy <python@sffjunkie.co.uk>

## Version History

Version Description
0.1 First release
0.2 Fix for bug 554041 submitted by Derek_ / John Dimatos
0.3
• Changed to Apache V2.0 license.
• Fix for bug 555508 submitted by me.
• US state capitals and other cities added.
0.4
• Duplicate city names could not be accessed.
• Sun calculations for some cities failed with times outside valid ranges.
• Fixes for city data.
• Added calculation for moon phase.