UPSC Civil Service Exam Questions - Engineering

Q1:

Which one of the follewing represents a circumpolar star ?

A Upper culmination above horizon, lower culmination below horizon

B Both upper and lower culminations below horizon

C Both upper and lower culminations above horizon

D Altitude at upper culmination is minimum

ANS:C - Both upper and lower culminations above horizon

A circumpolar star is a star, as viewed from a given latitude on Earth, that never sets below the horizon due to its apparent proximity to one of the celestial poles. Circumpolar stars are therefore visible from said location toward the nearest pole for the entire night on every night of the year (and would be continuously visible throughout the day too, were they not overwhelmed by the Sun's glare).