No moonrise when official almanac states there is (ditto sunrise)

[gullivertortoise]

INPUT
place = 'Auckland'
region = 'New Zealand'
latitude = -36.8509
longitude = 174.7645
elevation = 196  # metres above sea level
Timezone: Pacific/Auckland

Date: 2023-01-13
OUTPUT
moonrise: None     moonset: 2023-01-13 11:37:00+13:00

Date: 2023-01-27
OUTPUT
moonrise:   Moon never rises on this date.    moonset: 2023-01-27 23:58:00+13:00

NOTE: The above times are New Zealand Daylight Saving Time (New Zealand Standard Time +01:00) in operation at these lunar events.

New Zealand Nautical Almanac 2022/23
(https://www.linz.govt.nz/sites/default/files/cust/hydro_almanac_moonrise-moonset_auckland_202223.pdf)
13 January 2023
moonrise: 23:14     moonset:10:37       These times are New Zealand Standard Time - add one hour for Daylight Saving Time

27 January 2023
moonrise: 11:15      moonset: 22:58      These times are New Zealand Standard Time - add one hour for Daylight Saving Time

In the absence of a moonrise or moonset, Astral.moon appears to returns None (when a moonrise (moonset) is found but is not for the required dat) - or a ValueError if no moonrise(moonset) is found.

Hope this is useful.

[jmorgancusick]

Have a similar issue, a missing moonset in Salt Lake City. To reproduce:

import datetime
from astral.geocoder import database, lookup
from astral.moon import moonrise, moonset

def test():
  format_data = "%m/%d/%y %H:%M:%S.%f %Z"

  print("====== test missing data on 5/17/23 =========")
  day = datetime.date(year=2023, month=5, day=17)

  slc = lookup("Salt Lake City", database())
  try:
    print(moonset(slc.observer, day).strftime(format_data))
  except ValueError as e:
    print(f'caught exception: {str(e)}')

test()

Running this results in:

❯ python3 test.py
====== test missing data on 5/17/23 =========
caught exception: Moon never sets on this date, at this location

This seems incorrect, since there was a moonset reported by timeanddate.com and pyephem

dawn, dusk, moonrise and moonset calculations for the rest of May look good, just this oddity.

[martytyty2098]

Similar problem, missing moonrise at Russia/Moscow 2024 January 5
ValueError: Moon never rises on this date, at this location

Minimal repro:

import datetime
from astral.moon import moonrise
import astral

def repro(lat = 55.7522200, long = 37.6155600, search_date = datetime.date(2024, 1, 13)):
    """Latitude and longitude of Russia/Moscow 2024 January 5\n
    ValueError: Moon never rises on this date, at this location"""
    city = astral.LocationInfo(latitude=lat, longitude=long)
    rise = moonrise(city.observer, search_date)

    return rise

repro()

Im using Python 3.11.7

Every other moonrise in this month looks correct according to timeanddate.com

The following dates also produce this error:
2024-02-03
2024-03-03
2024-03-31
2024-04-30
2024-06-06
2024-07-05
2024-08-03
2024-09-01
2024-09-29
2024-10-28
2024-11-26
2024-12-24

[magnus-bakke]

Similar problem, no sunset in a very specific location in Texas on Jan 10, 2025:

now = datetime.datetime(2025, 1, 10, tzinfo=timezone.utc)
lat = 28.5 # and more specific
lon = -99.7 # and more specific
observer = LocationInfo("Example", "World", "UTC", lat, lon).observer
sun(observer, now)
# ValueError("Unable to find a sunset time on the date specified")

It does not fail for any other dates in January, or for less specific coords (I tried 28, -99). It does fail for more specific coords. Seems to be about a ~100 square mile area that's problematic.