1 The English language is constantly adding words to its repertoire. 2  Each year you may see a few creep into the vernacular that don't appear in the dictionary. 3  They could appeaâ¦. 4  Helping a Young Girl Understand Her First Menstrual Period Most girls experience their first menstrual period between the ages of 12 and 13.
It is also the length of a sidereal day -- the time it takes the earth to rotate 360Â°. A sidereal day could be measured using fixed stars. In conclusion the actual period of rotation of the earth is 23 hours 56 minutes and 4 seconds or 86,164 seconds.
AT the equator the Solar rotation period is 24.47 days which is the sidereal motion and a synodic rotation period of 26.24 days, which is the time for a fixed feature of the Sun to rotate to the same apparent position as viewed from Earth.