When Lilacs Last in the Dooryard Bloom'd Whitman's encounter with the lilacs in bloom in his mother's yard caused the flowers to become "viscerally bound to the memory of Lincoln's death". According to Gregory Eiselein: In the weeks before Lincoln's assassination, Whitman observed the planet Venus shining brightly in the evening sky. He later wrote of the observation, "Nor earth nor sky ever knew spectacles of superber beauty than some of the nights lately here. The western star, Venus, in the earlier hours of evening, has never been so large, so clear; it seems as if it told something, as if it held rapport indulgent with humanity,
Sunrise is 34 arcminutes, though this amount varies based on atmospheric conditions. Also, unlike most other solar measurements, sunrise occurs when the Sun's "upper limb", rather than its center, appears to cross the horizon. The apparent radius of the Sun at the horizon is 16 arcminutes. These two angles combine to define sunrise to occur when the Sun's center is 50 arcminutes below the horizon, or 90.83° from the zenith. The timing of sunrise varies throughout the year and is also affected by the viewer's longitude and latitude, altitude, and time zone. These changes are driven by the axial tilt of