The time interval from when the given star passes directly overhead to when it next passed directly overhead, is defined as

A. one sidereal day

B. one solar day

C. both the terms are similar, so any of these may be used

D. None of the above

Answer: Option A

Solution(By Examveda Team)

A measurement of the sidereal day is made by noting the time at which a particular star passes the celestial meridian (i.e. directly overhead) on two sucessive nights. On Earth, a sidereal day lasts for 23 hours 56 minutes 4.091 seconds, which is slightly shorter than the solar day measured from noon to noon.