E CLIPSES SPI

B RAIN P OP E CLIPSE

Today you will learn about effects shadow can have on your view of the sun and moon from Earth.

T HE E ARTH -M OON -S UN S YSTEM You already know that the moon revolves in orbit around the Earth. At the same time, Earth orbits the sun. Earth and the moon travel around the sun together.

W HY DO WE HAVE E CLIPSES ? As they revolve, their positions change. The position of their shadows also change. At certain times, Earth and the moon cast shadow on each other. An eclipse occurs when one object in space cast a shadow on another object in space. The changing positions of the moon, the sun, and Earth when compared to each other causes eclipses. Eclipses only occur when all three bodies line up in a particular way.

S OLAR E CLIPSE The moons orbit around Earth is slightly tilted compared to Earth’s orbit around the sun. This means that sometimes the moon travels a little bit above or below Earth’s path around the sun. When the moon comes between Earth and the sun this is called a solar eclipse. Since the moon goes around Earth about once a month you might expect a solar eclipse to happen often. A solar eclipse only takes place during a new moon. The must be in its new moon phases AND it much be lined up directly between the sun and the Earth. The next solar eclipse from the US will occur in 2017.

L UNAR E CLIPSE Lunar Eclipse- occurs when Earth comes between the sun and the moon, and Earth casts a shadow on the moon. Earth blocks the sun’s light from reaching the moon. From Earth a lunar eclipse looks like all or part of the moon disappears and then appears again. A Lunar eclipse can only happen during a full moon. Earth shadow only covers the moon if the moon is DIRECTLY lined up with the earth and the sun. During a totally lunar eclipse you see a curved shadow on the moon. The moon continues to move in its orbit until it is completely inside Earth’s shadow.