nikhil 22-08-1988 time of birth 7.21 AM?

Astronomical time-keeping is very complex. Leap seconds are introduced every few years to compensate for the slowing of the rotation of the Earth. Timezones are broad, and official noon usually doesn't agree with local solar noon. Daylight savings comes and goes, and the usage changes over years. The length of a day changes as the Earth wobbles and the Moon moves closer and further away. The length of a year is forced to be a number of days, although the period the Earth's orbit around the sun is not an exact number of days. In short, accurate measurement of time for something as imprecise and useless as astrology is absurd.