astropy / astroplan

Observation planning package for astronomers – maintainer @bmorris3
https://astroplan.readthedocs.io/en/latest/
BSD 3-Clause "New" or "Revised" License
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Shouldn't rise and set be constant over a 24hr? #509

Closed mirosaide closed 3 years ago

mirosaide commented 3 years ago

Hi,

I am calculating the rise and set of Barnard's star for different locations on the globe. Somenthing that is letting me confused is the fact that the rise and set are not constant over 24hr period.

Am I doing something wrong or it's just the way it is.

The code is below:

`` from astropy.visualization import astropy_mpl_style, quantity_support plt.style.use(astropy_mpl_style) quantity_support() import astropy.units as u from astropy.time import Time from astropy.coordinates import SkyCoord, EarthLocation, AltAz from astroplan import Observer, FixedTarget from astropy.time import Time from astroplan import download_IERS_A download_IERS_A

time = Time("2020-05-12 00:00:00",format='iso') target = SkyCoord.from_name("Barnard's star") Location = Observer(latitude=42.248u.deg, longitude=-122.567u.deg) star_rise_time = Location.target_rise_time(time, target, which='nearest') star_set_time = Location.target_set_time(time, target, which='nearest')

bmorris3 commented 3 years ago

Hi,

Does this FAQ page answer your question?

https://astroplan.readthedocs.io/en/latest/faq/precision.html#why-is-my-target-above-below-the-horizon-at-the-rise-set-time

mirosaide commented 3 years ago

It Does. Thank you.