Final answer:
On the first day of spring, the Sun rises directly east due to the position of the Sun at the vernal equinox intersecting the ecliptic and celestial equator.
Step-by-step explanation:
On the first day of spring, also known as the vernal equinox, the Sun rises directly east. This is because at the equinoxes, day and night are approximately equal, which occurs on or around March 21st and September 21st. During these times, the Sun's position is at one of the intersections between the ecliptic and the celestial equator, resulting in it rising due east and setting due west for all observers on Earth. The sunrise and sunset positions only align exactly east and west on these two days of the year.