Questions tagged [right-ascension]
Questions regarding the second ordinate of the equatorial celestial system.
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Hour angle to Right Ascension correct when the longitude is positive
I'm developing a Astronomical software using the formulas from the book: "Practical astronomy with your Calculator and Spreadsheet", but I'm having some problems to get the right ascension ...
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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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Position of Hamal (alpha Arietis) between 1582 and 1588
Between 1582 and 1588, Tycho Brahe observed $\alpha$ Arietis from Uraniborg (55°54′28″N 12°41′48″E) on at least 27 separate occasions and made a record of the right ascension of the star (see Opera ...
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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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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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How to convert GMST to GMST° (degrees) for calculating RA [duplicate]
For calculating the Right Ascension of the moon I need the GMST (Greenwich Mean Sidereal Time) in Degrees.
I have found the formula
GMST = 100.4606184 + 0.9856473662862 * D + H * 15,
D = number of ...
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Convert RA from hours to h:m:s
I'm working on a small mount controller software in Python. From the ASCOM standard, right ascension is reported in unit of hours.
How do I convert from hours to hours:min:sec?
Here is my attempt in ...
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How to calculate Local Sidereal Time from RA of a star and Longitude of Observer
I have been banging my head against a wall trying to understand these time conversions and the relation between all of these astronomical measurements.
This is the question I am currently working on, ...
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How to get the right ascension of the Moon?
Is there any approximate way to calculate the right ascension of the Moon? I already got declination but still, need the right ascension to calculate the final position of the moon. Thanks for all ...
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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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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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How to calculate the local time of sunrise and azimuth of rising point of Sirius?
I know that right ascension equals to $6^h45^m$ and declination equals to $-16°43'$. I need to calculate local time of sunrise and azimuth of rising point of Sirius on 23 of September for an ...
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