International Women's Day first emerged from the activities of labour movements at the turn of the twentieth century in North America and across Europe. Since those early years, International Women's Day has assumed a new global dimension for women in developed and developing countries alike.
The shadowed portion is entirely hidden from view. The first quarter and third quarter moons (both often called a half moon), happen when the moon is at a 90 degree angle with respect to the earth and sun. So we are seeing exactly half of the moon illuminated and half in shadow.
The umbra is the dark center portion of a shadow. The Moon's umbra causes total solar eclipses, and the Earth's umbra is involved in total and partial lunar eclipses. The umbra is the darkest type of shadow. The umbra is the dark, central part of the shadow. If we are within the Moon's umbra, we see a total solar eclipse.