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1 vote
1 answer
322 views

At what rate does the right ascension and declination of a planet, the sun and moon change per hour?

I'm currently building a web app and am getting the RA's and Dec's of solar system objects based on date and time chosen by the user. Then using the gmst for 0 hours of the date, the app calculates ...
Peter Orji's user avatar
1 vote
1 answer
101 views

At what time of the day of autumnal equinox the Sun's equatorial coordinates reach max value?

I'm trying to solve this task: At what point in time of autumnal equinox day, at sunrise or sunset will a) the declination of the Sun b) the right ascension of the Sun reach the maximum value? I'm ...
ALiCe P.'s user avatar
  • 1,017
0 votes
1 answer
974 views

Sun right ascension and declination at date with different values on different calculators and also with my implementation

I'm reading the book "Practical Astronomy with your Calculator or Spreadsheet 4th Edition" implementing its formulas with C++. Now, I have implemented formula 47 "Calculating orbits ...
VansFannel's user avatar
0 votes
1 answer
2k views

RA and Dec of the Sun at J2000

I'm in the somewhat awkward position of asking something that, despite me thinking there should be hundreds and hundreds of web pages and datasets showing this particular value, I've been unable to ...
Izhido's user avatar
  • 103
2 votes
3 answers
2k views

How to calculate solar coordinates. (Right Ascension, Declination, and ultimately the Altitude and Azimuth of the Sun)

As the title says I am trying to calculate solar coordinates of the sun for a given location and time. I have spent many 10's of hours on this without success so I will sincerely appreciate help on ...
noCodeMonkeys's user avatar
1 vote
2 answers
690 views

When does a star rise with the sun?

Problem: Suppose an observer's latitude is 45 S and a star's RA/DEC is 3h15min/41S. On what date will the sun set with the star. I have been stuck on this problem for a while. I found out that the ...
Arhaan Ahmad's user avatar