Which one of the following is the time required for the Earth to return to a given point in its orbit with reference to fixed stars, called?

The time required for the Earth to complete one full orbit around the Sun with reference to fixed stars is known as the sidereal year [2]. This period represents the actual time taken for the Earth to return to the same position in its orbit relative to the celestial background of stars [t2][t5]. In contrast, the tropical year (or solar year) is measured between successive vernal equinoxes and is approximately 20 minutes shorter than the sidereal year due to the axial precession of the Earth [c1][t2]. While the tropical year is used for the Gregorian calendar to maintain synchronization with the seasons, the sidereal year reflects the true orbital period of the Earth relative to the inertial frame of the stars [t4][t6]. A lunar year, conversely, is based on twelve synodic months of the Moon and is significantly shorter, at approximately 354 days [t6].

Sources

1. [1] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 11: Keeping Time with the Skies > A step further > p. 180
2. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 19: The Motions of The Earth and Their Effects > Sidereal Period > p. 260