For a body to be circumpolar, the body should always be above the rational horizon i.e the body should not set. Therefore, a circumpolar body will have upper transit (upper meridian passage) which is above the elevated pole and lower transit (lower meridian passage) which is below the elevated pole.Condition required for a body to be circumpolar:Lat + Dec > 90° (For the body not to set)Latitude and declination should be the same name.1. North Latitude - Lat < Dec2. North Latitude - Lat > Dec3. South Latitude - Lat < Dec4. … [Read more...]
Rising and Setting of Celestial Bodies
As the Earth rotates on its axis from west to east, all heavenly bodies appear to rise in the east, move westwards, gaining in altitude until it is on the observer's meridian (culminate or transit the meridian). After culmination, it continues to move westwards decreasing in altitude till it sets over the western horizon.For a stationary observer, the interval between rising and culmination of a body will be equal to the interval between its culmination and setting, provided its declination remains unchanged.Also under the same circumstances, its amplitude at rising will be equal to … [Read more...]