Final answer:
A total solar eclipse occurs when observers are within the Sun's umbra, the darkest part of the Moon's shadow where the Sun gets completely obscured by the Moon.
Step-by-step explanation:
A total solar eclipse occurs for people in the Sun's umbra. A total solar eclipse occurs when observers are within the Sun's umbra, the darkest part of the Moon's shadow where the Sun gets completely obscured by the Moon. During a total solar eclipse, the Moon's darkest shadow, or the umbra, intersects the ground at a small point on Earth's surface.
Anyone within the small area covered by the tip of the Moon's shadow will witness the Sun becoming completely obscured by the Moon, resulting in a total solar eclipse. On the other hand, observers in the penumbra, the lighter, more diffuse region of the Moon's shadow, will see only a part of the Sun being covered, experiencing a partial solar eclipse.