a: Four types of shadow regions-umbra (U), inner penumbra (P2), outer

Michal Valient's research works Comenius University Bratislava, Bratislava and other places

There are 2 different parts to a shadow. The umbra and the

How long does it take for the moon's shadow to move across Earth

Shadow detection results on various IKONOS and GeoEye images

Diagram of Umbra and Penumbra - NASA

a: Four types of shadow regions-umbra (U), inner penumbra (P2

The Parts of the Moon's Shadow

Reference Section 4

Umbra and Penumbra region of Earth-Sun system.

Shadow Science – Types of Shadows

Figure 3-2