The phrase "at declination" is correct and usable in written English.
It can be used in contexts related to astronomy, navigation, or geography, referring to the angle of an object relative to the celestial equator.
Example: "The star's position is measured at declination of 30 degrees north."
Alternatives: "at an angle" or "in terms of declination".
When the Sun is at declination zero (at the vernal and autumnal equinoxes) it is therefore up for twelve hours and and down for twelve hours.
Objects at declination zero (or directly "above" the Earth's equator (see our explanation of right ascension and declination) are up for twelve hours and down for twelve hours.
As it is at declination −50° to −70°, the whole constellation is only visible south of latitude 30° N. The official constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of 14 segments.
Good agreement is obtained at assumed declination of 15° between the anisotropy and geometrical axes of the resistors.
Hence, if the Sun is at a declination of 23.5 degrees (which it will be close to summer) in the constellation of Gemini, then the Moon will be at a declination of -23.5 degrees in the constellation of Sagittarius.
The center of the Milky Way is in the constellation Sagittarius, which is at a declination of around -30 degrees.
Then you work out how long an object at that declination is up in the sky for give your lattitude on Earth.
The Magellanic Clouds are at a declination of about -70 degrees, so that the farthest northern latitude from which they can be seen is about 20 degrees.
As you know, all objects in the sky go in circles around the celestial pole (due to Earth's rotation), and hence from a latitude of 20 degrees north, an object at a declination of -70 degrees will just touch the horizon for a few minutes before setting.
The effect of the thermospheric vertical neutral wind on vertical total electron content (vTEC) variations including longitudinal anomaly, remaining winter anomaly, mid-latitude summer night anomaly, and semiannual anomaly is studied at mid-latitude regions around zero magnetic declination at midnight during high solar activity.
We studied the effect of the thermospheric vertical neutral wind on vTEC variations, including longitudinal anomaly, remaining winter anomaly, MSNA, and semiannual anomaly at different mid-latitudes regions around zero magnetic declination at midnight during high solar activity.
