Questions tagged [sunset]
The sunset tag has no usage guidance.
38
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What is the distance between sunrise and sunset along a parallel of latitude for declination other than 0?
I would like to calculate the distance between sunrise and sunset along a parallel of latitude, e.g., 45 degrees north.
What I've done is:
Earth's circumference at the equator is 40075 km.
Earth's ...
- 204
6
votes
1
answer
326
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Geometric effect on sun's position in the sky at the equator
This question is about an explanation of "Sunrise and Sunset Times Near the Solstices" on the official website of the US Naval Observatory.
It is mentioned in the explanation article that,
...
- 133
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How can the new moon set before the sun, as will happen in some locales on November 13, 2023?
I have somewhat of an interest in sighting the new moon. I recently heard a lecture by someone who had written a program to provide the conditions for the first new moon sighting for any location for ...
4
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1
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Sidereal time of rising and setting of the sun on the arctic circle
$$
cos(h)= -tan(\delta)tan(\phi)
$$
$$
\Theta = h + \alpha
$$
if these two equations are the correct equations to solve the following question why doesnt it yield the same answer for the sideral ...
- 125
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Where can I download the historic sunrise and sunset times for a location?
As the question indicates, I would like to know the sunrise and sunset times of a location. This is to evaluate the impact of day and night variations of a time series. Is there a way to download this ...
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Why is moonrise/moonset before sunrise/sunset on some days but after on others?
While looking at the daily forcasts for the week on The Weather Channel app on my phone I noticed that today, Thursday the 18th, both moonrise and moonset are roughly half an hour to an hour BEFORE ...
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Display the lines of solar altitude on the map
Following this question:
Calculate lines of equal solar altitude
I would like to have the possibility of displaying the lines of equal solar altitude on the map as per the image below:
including also ...
- 204
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math tool to compute time of sunrise and sunset
What is the mathematical tool that enable to compute time of sunrise and time of sunset at a specific geographical location in the same part of a year, say given month and day exactly?
I have noticed ...
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How to roughly calculate sunrise and sunset with a spreadsheet application
I am looking for a way to roughly calculate sunrise and sunset for a given lon/lat in mid Europe for each day of a year using a spreadsheet application. The thing doesn’t need to be very precise, but ...
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Meaning of $\cos H$ in the rising and setting formula
In the rising and setting formula$$\cos H=-\frac{\left(\sin\nu+\sin\phi\sin\delta\right)}{\cos\phi\cos\delta},$$ $H$ is hour angle, $\nu$ is vertical shift, $\delta$ is declination and $\phi$ is the ...
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How to find the first Julian day with the same Earth-Sun constellation
There are quite some sources for astronomical calculation formulas, e.g. Astronomy Answers: Position of the Sun, which is e.g. used by KDE's Night Color plugin to calculate the time of a sunset or ...
- 121
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Why do sunrise/sunset times (for a given location) vary based on the source of the data?
I've noticed that different reputable weather websites will give different times for sunrise/sunset for the exact same location. I've seen variation by 25 minutes or more, for sunset on the same date ...
- 113
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Why isn't Spring equinox on 1st of April?
AFAIK the summer and and winter solstices are based on longest day and longest night doesn't fall on 1st of Jan and July 1st because we consider the day to begin and end when the middle of the sun is ...
4
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1
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How can I calculate my position (lat/lon) given a sequence of solar-elevation measurements at known times?
The "forward" problem (given time and lat/lon, find solar position angles) is well documented, e.g. here. I am trying to figure out the "inverse" problem: given time and [a ...
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Daytime length and sunrise / set cardinal directions
Let me illustrate the question with an example. On Feb 2nd 2022, the sun rises in Los Angeles at cardinal direction 110 and sets in direction 250 (according to timedate website). This means that the ...
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