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Empty meridian transit time #612

@libre-hackerman

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@libre-hackerman

Hi, I'm building a visual observing planner and I'm trying to get meridian transit times. For DSOs and planets I'm getting no issues, but if I try creating a FixedTarget from the SkyCoord returned by astropy's get_body (like I do for the planets), I get a wrong transit time. So researching, I found astroplan uses a special target for the Moon: MoonFlag, and replacing the FixedTarget with MoonFlag I got the right result (at least for tonight). But testing another date, it would return and empty Time object. Here's a sample code to reproduce the problem:

import astropy.units as u
from astroplan import Observer
from astropy.time import Time
from astroplan.target import MoonFlag

place = Observer(latitude=40.41*u.deg,
                 longitude=-3.7*u.deg,
                 elevation=650*u.m,
                 name='Madrid',
                 timezone='Europe/Madrid')

t = Time('2025-06-11 00:14:21.664266')
meridian_time = place.target_meridian_transit_time(t, MoonFlag)
# Should be the 10th at 23:56 UTC
print(meridian_time)  # Returns empty

t = Time('2025-01-10 00:14:21.664266')  # Tonight for example
meridian_time = place.target_meridian_transit_time(t, MoonFlag)
print(meridian_time)  # Gives correct result

What could be the reason? Thank you very much.

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