Questions tagged [horizon]
The horizon tag has no usage guidance.
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Where does the ecliptic cross the horizon during the course of a night?
The Nebra Sky Disc has side-arcs which are interpreted as marking the extent of movement of the sunrise and sunset, during the course of a year. I think they can also be interpreted as marking the ...
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Horizons SPK file with a different coordinate center than I asked for
I am using the JPL horizons app to generate an SPK file for Chiron (ID: 20002060) with respect to the solar system barycenter (ID: 0). However, the generated SPK file says the center is with respect ...
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Demonstration- formula for angle between horizon and ecliptic
The most precise and quite intuitive formula I could find online is here: https://www.celestialprogramming.com/snippets/angleBetweenEclipticAndHorizon.html
$$\cos I = \cos ϵ \sin ϕ − \sin ϵ \cos ϕ \...
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New moon rise same spot on horizon as sunrise, almost same time [closed]
I witnessed the new moon rise just ahead of a sunrise at the very same spot on the horizon. How often could I plan on looking for that occurrence again?
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Crossing of particle horizon and a past light cone
What does it mean when a light cone intersects a particle horizon? Like here, about 2 billion years after the big bang? Does it have any significance? I went through a few simple equations and the ...
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Small Angle Approximation Discrepancy in Horizon Dip Angle
Let's get back to the classic astronomical problem of calculating horizontal dip angle using small angle approximations. Let, our observer is a point object situated at an height $h$ on the earth ...
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What is the relationship between the shape of the analemma and the sun's azimuth at sunset at a given latitude?
I want to know how the sun's azimuth at sunset changes over the course of a year.
At first, I thought it would have purely sinusoidal motion, hitting its maxima and minima at the solstices, and ...
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Can Mercury be seen from the 60th parallel north on Earth? Shetland, Faroe, Norway, St Petersburg, Alaska
I'm originally from a city in Spain which is 40 degrees north, and I used to watch Mercury (naked eye and telescope) every time I had the opportunity, that is, when Mercury was at maximum elongation ...
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Calculate viewing times at a location - when location has an obstruction
My most convenient viewing location is my backyard. It also has an obstructed view of the sky - trees. This means that just knowing the rise and set times of a planet does not let me know when, or ...
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Is the appearance of the twilight not constant in the interval before the sunrise?
I've been told by an astronomer in past, that the appearance of the twilight isn't constant in the interval before the sunrise. That is to say that not every day the earth is going at the same speed, ...
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Solar Azimuth angle Derivation
I tried posting this on math stack exchange to no avail so I thought maybe it's more relevant here :
I know a similar question has been posted here before but no links to any mathematical derivations ...
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How to find the moons maximum culmination at a location
Forgive me if my terminology is incorrect, but is there someway or somewhere when I can calculate based on my location when the moon will be at the highest point in the sky overhead based on my ...
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A plot of the Moon-rise/sets on the Horizon Location
We have been trying to see where the moon rises/sets on the horizon. Unfortunately, the moon is not cooperating. Even when we know the moon rise/set times (timeanddate.com), we often cannot find ...
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Is there a more permanent way to set up an Artificial Horizon?
For the last few months we have been constantly setting up an Artificial Horizon (Davis Instruments) using motor oil as the liquid. We discovered that it is very hard to take a reading off of it ...
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Calculate position of sun in sky
I would like to calculate the angle formed by the sun and the horizon for any hour of the day and any day of the year for a particular place on Earth. So like: what is the angle of the sun to the ...
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