Asolar day is the time it takes earth to rotate on its axis between two consecutive solar positions (for example, high noon to high noon or sunset to sunset). a sidereal day is the time it takes earth to rotate on its axis between two consecutive positions of a distant star (vega on the eastern horizon to vega again on the eastern horizon). which is longer?

Solar Day

Explanation: As explained above, a Solar Day is the time it takes to the earth to rotate between to Solar Position. This time is taken as reference to calculate the day, so this times equals to 24 hours.}

However the Sideral Day is the time on which the Eart rotates between two consecutives position on a distant star. The Sideral day is shorter because both Earth Rotanting Movements are counter-clockwise.

The Earth moves around the sun and around his own axis. Because of this, the earth after doing a full rotation, needs to compensate a extra degree to face the sun at the same spot, so the movement is longer.