Eclipses An eclipse occurs when the Sun’s light is blocked by either the Moon or the Earth.
Solar eclipse
A solar eclipse occurs when the Moon moves between the Sun and the Earth. This causes the Moon’s shadow to be cast onto the surface of the Earth.
Earth Sun Moon Umbra Penumbra
Penumbra :Fig. 36.15 A solar eclipse
CONCENTRATE! The Sun’s UV radiation can burn the retinas in our eyes, leading to permanent damage or even blindness. Never look directly at the Sun. Always wear special eclipse glasses or use a pinhole camera to view an eclipse.
)Fig. 36.16 Always wear eye protection to view an eclipse
Lunar eclipse
A lunar eclipse occurs when the Earth moves between the Sun and the Moon. This causes the Earth’s shadow to be cast onto the surface of the Moon. Sun
Earth Moon Umbra Penumbra :Fig. 36.17 A lunar eclipse
The darkest part of the shadow cast by the Moon or Earth during an eclipse is called the umbra. This is caused when the light from the Sun is completely blocked by the Moon or Earth.
When the light from the Sun is only partially blocked by the Moon or Earth, the shadow cast is called the penumbra.
Eureka
Ancient Greeks were able to work out the diameter of the Earth using data they gathered from lunar eclipses.
Eclipses do not happen every month because the Earth, Moon and Sun do not always line up exactly. Lunar eclipses are more common than solar eclipses.
14. In groups, research another scientific discovery that occurred from the observation of eclipses. ?