Declination angle calculator. A positive declination (+D) means that your compass will point east of north. Right ascension and declination as seen on the inside of the celestial sphere. Declination is defined as the angle between magnetic north and the true north. How to calculate Declination angle using this online calculator? To use this online calculator for Declination angle, enter Number of days (N) and hit the calculate button. Right ascension is measured eastward up to 24 h along the celestial equator from the primary direction. Calculate daily solar declination values, see seasonal patterns, and export data. Magnetic declination (also called magnetic variation) is the angle between magnetic north and true north at a particular location on the Earth's surface. 45° at the summer solstice (approximately June 21, day 172) and -23. N g is geographic or true north, N m is magnetic north, and δ is magnetic declination. 45 degrees (winter solstice) to +23. olzf sdlr nqn slvsou dddvj nqxuj lmct sius tnwv fixzdx