Questions tagged [declination]
Questions regarding one of the two main angles(coordinates) of an object perceived by an observer on Earth.
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What's the name of the projection onto the celestial sphere of the tropic of cancer?
The projection of earth's equator is the celestial equator. The ecliptic oscillates above and below it in a year, and the furthest north it goes is the projection onto the celestial sphere of the ...
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calculate declination and right ascension with limited information
I'm trying to make a game with high accuracy moon position so I followed some equations on geoastro.de Basics of Positional Astronomy and Ephemerides and with some help from the questions answers, I ...
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How does azimuth of moonrise/moonset vary by longitude?
I found a useful formula for calculating the azimuth of moonrise/moonset, which can be found in this post:
How does moonrise/moonset azimuth vary with time?
However the formula refers to the fixed ...
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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 ...
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How to even approach this type of question
Can someone tell me how one would approach this type of question. is there an equation we would use or something of the sort.
Ths solution to this question is given below but I just want to understand ...
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Definition for Day Angle
I am searching for a proper definition for day angle.
The day angle $\Gamma$ is calculated as follows:$$\Gamma = 2\pi\cdot \frac{n_{day} - 1}{365}$$
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Plotting galactic latitude in Ra vs Dec plane
I have an open cluster with calculated percentage of polarization and position angle. I want to have it's scatter plot in Ra vs Dec plane and superimpose a galactic parallel on it. How to plot the ...
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Does RA/Dec vary with the Earth's orbit around the Sun?
I think the RA and Dec of a celestial object should change (ever so slightly) with the Earth's position in its orbit. So do we ignore this in general?
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Right ascension and declination visible at that local time and location
If I know the local time of an observer and her/his latitude and longitude, how can I know which stars are visible?
I'm developing a planetarium software using the Hipparcos Catalogue. I have also ...
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Figuring out camera pitch and roll given RA and DEC of center of image, as well as lat,long of camera and time taken
What I am trying to figure out is how to get the camera pitch and roll, as described in this image (the green yaw line is where the camera sensor is pointing
if given a RA, DEC (of center of image,ie ...
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Why isn't Amplitude the same as Declination?
From the way I understand Amplitude and Declination, it seems to me that they should always be the same, yet they are not, why?
P.S. In the picture I am imagining that the declination remains constant ...
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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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What is the "sunrise equation" for non-constant declination component?
The standard Sunrise Equation (refraction neglected) is this:
$$ \cos(\text{hour angle}) = \tan(\text{declination})\tan(\text{latitude}) $$
This equation - which really has nothing to do with the Sun ...
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When was/will Polaris's declination be maximised?
When was/will Polaris's declination be maximised?
In what year was/will Polaris be closest to the north celestial pole.
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Azimuth and Altitude angle between two points in the sky
I want to know how to correctly calculate altitude and azimuth difference, separately, between two points in the sky. The same way will be with icrs coordinates.
For the altitude difference, I simply ...
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