To calculate the distance we need to know the declination of the sun on a given day.
in the face of this declination of the proposition
The actual declination letter disappeared from the file.
It's easy enough to gauge an asteroid's longitude and latitude (ascension and declination in astro-speak), but figuring out its current celestial position is tricky.
Proposals were being made to solve the longitude problem and in 1673 one based on magnetic declination was proposed by a certain Henry Bond.
He also determined the latitude and longitude of many stars, and measured the greatest declination of the planet Mercury.
The compass needle and a knowledge of magnetic declination , the angle between the magnetic north and geographic north, were developments from this knowledge; they were described by Shen Kua in 1088.
On the North Rim the difference between map and compass is 15 east, a distinction known as magnetic declination .
He also studied magnetic declination and was the first to observe the secular variation.
Also every month, the Moon will reach its minimum declination at 18 north or south.