circumpolar region | has coordinates whose equatorial latitude is greater than the Earth latitude of the observer minus 90 degrees |  |
is a part of celestial sphere |  |
has purpose to define a part of the sky which can be observed all year at the observers location |  |
has definition a region defined by an equatorial latitude above which stars are visible all year (depends on observers location on Earth) |  |
is an instance of equatorial sky area |  |
equatorial sky area | is defined using equatorial coordinates |  |
quantity | has unit |  |
number | has value |  |